- Email: [email protected]
Perceived level of performance impairment caused by alcohol and restricted sleep
Transportation Research Part F 41 (2016) 113–123
Contents lists available at ScienceDirect
Transportation Research Part F journal homepage: www.elsevier.com/locate/trf
Perceived level of performance impairment caused by alcohol and restricted sleep Ephraim S. Grossman a,⇑, Tova Rosenbloom b a b
The Interdisciplinary Department of Social Sciences, Bar Ilan University, Ramat-Gan, Israel Management Department, Bar Ilan University, Ramat-Gan, Israel
a r t i c l e
i n f o
Article history: Received 20 January 2015 Received in revised form 25 April 2016 Accepted 1 June 2016
Keywords: Alcohol Sleep restriction Impairment Perception Assessment
a b s t r a c t The aim of the current study was to investigate people’s perceptions towards the ability to perform various tasks (transport-related and other tasks) under the influence of alcohol and prolonged wakefulness. We assumed that people will assess that after alcohol consumption performance is damaged more than after sleep restriction. In addition we assumed that participants will relate performance impairment to the level of sleep loss. Participants (525 men and 620 women) were asked to refer to eighteen descriptions of imaginary situations (scenarios) where someone was asked to perform a duty under a certain awareness condition either after alcohol consumption or after total or partial sleep restriction (four levels). Of the eighteen scenarios, three were related to transport safety such as ambulance driver, a traffic policeman and a pilot. Participants were asked to rate the degree of fitness of the described person in each scenario on a 0–100 scale. The results show that people considered the ability to perform various tasks after absolute sleep restriction as more impaired than in other conditions, with alcohol as second worse, followed by performing after the conditions of partial sleep restriction. Also, it has been found that more sleep was related to better performance. Within life threatening tasks, the alcohol and sleep restriction conditions did not differ in ratings and were significantly lower than each one of the sleep conditions. Furthermore, transportation activities were assessed as more impaired than non-transport activities after alcohol consumption and no sleep but less impaired than non-transport activities after restricted sleep. Ó 2016 Elsevier Ltd. All rights reserved.
1. Introduction More than half of the population in industrialized countries report insufficient sleep on a regular basis (International Bedroom Poll, 2013). There is evidence that biological functions such as memory consolidation and problem solving benefit from a restful night’s sleep (Chapman, Benedict, Brooks, & Schioth, 2012). On the other hand sleep deprivation has been correlated with different pathologies (Kolb & Mandrup-Poulsen, 2010) and a lot of evidence has accumulated about an association of sleep deprivation with expressions of impaired psychomotor performance (for example, Howard et al., 2014). Tasks that involve motor as well as cognitive skills are impaired by sleep deprivation (Pilcher & Huffcutt, 1996). One of the consequences of sleep deprivation is fatigue and it may cause all kinds of accidents, including road accidents
⇑ Corresponding author at: Interdisciplinary Department of Social Sciences, Bar-Ilan University, Gehha Rd., Ramat-Gan 52900, Israel. Tel.: +972 50 5654695; fax: +972 3 7384039. E-mail address: [email protected] (E.S. Grossman). http://dx.doi.org/10.1016/j.trf.2016.06.002 1369-8478/Ó 2016 Elsevier Ltd. All rights reserved.
114
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
(McConnell, Bretz, & Dwyer, 2003). Driving is a complex task that requires skills such as attention, rapid response time and perception of driving velocity. These skills may decrease due to fatigue states (Campagne, Pebayle, & Muzet, 2004) and thus may increase the probability of accidents (Lianzhen & Yulong, 2014). In line with this, Rosenbloom, Beigel, and Eldror (2011) found that after sleep deprivation pedestrians are not aware to the danger in road crossing. The current research refers to prolonged wakefulness and restricted sleep that mean wakefulness over a whole day or sleep of less than the recommended optimum amount of sleep of eight hours. However, in literature there is a clear indication that restricted sleep may cause deterioration in functioning even after the first night of sleep restriction similarly to sleep deprivation (Belenky et al., 2003). For example, driver drowsiness caused by sleep restriction is believed to be a leading cause of motor vehicle accidents throughout the world (Jackson et al., 2016). Furthermore, there is evidence that brake reaction time in a harsh-braking test was significantly longer after insufficient sleep than after sufficient sleep (Miyata et al., 2010). Another crucial contributor of accidents is alcohol consumption. Irwin, Leveritt, Shum, and Desbrow (2013) showed a detrimental impact of alcohol consumption on cognitive performance. Deterioration in performance following alcohol consumption has been shown on a range of cognitive tasks that includes concentrated and divided attention and choice reaction time (Moskowitz & Fiorentino, 2000), and response inhibition to stop-signal and go/no-go tasks (Fillmore, 2007). The required motor skills and balance needed for proper driving operation make drivers after consuming alcohol more prone to severe injuries, particularly motorcyclists that drive on curves (Maistros, Schneider, & Savolainen, 2014). This was seen by the motorcyclists making the improper maneuver, grabbing the front brake and losing control of the motorcycle due to braking while cornering. The combination of alcohol consumption and driving causes dangerous behavior and becomes a major risk factor in road accidents. Although driving may be perceived as an automatic, routine and elemental activity it is actually a motor activity requiring, among other abilities, a high level of concentration, keen eyesight, proper motor function, a good memory, and a sound decision-making process (Moran, Baron-Epel, & Assi, 2010). Any physical or emotional impairment may increase the risk of involvement in a road accident, or of committing a traffic offence (Rosenbloom et al., 2011). So, many alcohol-related crashes occur all over the world, for example in the United States (NHTSA, FARS, 2012). More specifically, in the US there are around 10,000 fatalities involving a blood alcohol concentration (BAC) above legal limits (Maistros et al., 2014). As described, alcohol and sleep restriction, as well as sleep deprivation are possible causes of deterioration of cognitive and motor functioning. Studies that compared the damages caused by both factors found that moderate levels of fatigue can produce decrements in performance equivalent to those produced by BAC levels determined by law to prohibit safe automobile operation (Arnedt, Wilde, Munt, & MacLean, 2001). They found similar influence of alcohol consumption and sleep deprivation on tracking and speed variability while driving. Yegneswaran and Shapiro (2007) refer in their review to the comparison between the damages caused by alcohol and sleep deprivation. On the basis of previous studies (Maruff, Falleti, Collie, Darby, & McStephen, 2005). Yegneswaran and Shapiro conclude that staying awake for 24 h leads to reduced hand-to-eye coordination, which is similar to having a blood alcohol concentration (BAC) of 0.08%. Furthermore, based on Lamond and Dawson (1999) and Williamson and Feyer (2000) they conclude that deterioration of cognitive function after 17 h of sustained wakefulness is equivalent to that observed with a BAC of 0.05% or higher. Contrary to the knowledge currently held by the scientific community, a recent study (Sotos et al., 2015) reveals that only a small proportion of students were familiar with the concept of ‘the hazardous drinker’, the limits deemed hazardous and, in particular, the quantification of alcohol consumption. Dalawari and Scarbrough (2014) examined the knowledge of nonexperts of the influence that alcohol consumption has on boating and revealed that less than 25% of the participants answered correctly four of the five knowledge questions that were posed to them. A similar finding has been demonstrated by Buenaventura, Jones, and Schramm (2014) referring to awareness to the damages caused by fatigue. Growing research evidence points out that healthcare worker fatigue negatively impacts quality of care, patient safety, and other functions. Worker fatigue has been shown to increase the risk for patient care errors and employee injuries. Yet, there is little employee awareness or knowledge of worker fatigue and its impact on quality, safety and the ability to function as a high-reliability organization (Buenaventura et al., 2014). While recent scientific evidence shows that driving of sleep-deprived drivers may be as dangerous as driving under the influence of alcohol (Dalawari & Scarbrough, 2014), this perception may not be held by laymen. Williams, Davies, Thiele, Davidson, and MacLean (2012) used qualitative as well as quantitative methods in an in-depth testing of young drivers’ perceptions towards drivers who were driving after sleep deprivation and under the influence of alcohol. They found that young drivers were more tolerant towards drowsy drivers than drunk drivers. The authors concluded that although driving while sleep-deprived is perceived by some as a dangerous activity, the degree of blame and responsibility placed on the driver is not nearly as high as it is for driving under the influence of alcohol. Williams et al. (2012) encouraged further research for better understanding of this misconception. The current study expands the range of activities that may be impaired by alcohol and sleep deprivation beyond driving to many other everyday life functions that are based on motor or cognitive tasks such as quiz solving, giving a haircut, handling a psychiatric patient, and operating an airplane. Also, the current study distinguishes between degrees of sleep loss compared to alcohol consumption and enlarges the sample to more than 1000 people. Unlike the previous study that examined young drivers the current study is based on participants with an age range of 17–78, most of them holding a driving license. The aim of the current study was to learn about people’s perceptions towards the ability to perform various transport-related tasks under
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
115
the influence of alcohol and prolonged wakefulness. In the current research we dealt with performance of transport-related tasks as well as to other different tasks that are based on motor and/or cognitive skills such as sports, decision making, giving a haircut etc. Based on the literature described above, we hypothesized that (a) laymen will assess that people that consumed alcohol will be less able to perform their task than those who were after restricted sleep and that (b) people will assess that performance will be impaired as a function of the level of sleep loss so that the larger the deprivation the worse is the performance. 2. Method 2.1. Participants The participants were voluntarily recruited by students of Social Sciences Studies that distributed the questionnaires among their social network. The research has been approved by the ethics committee of the department. The participants signed agreement consent. The initial sample included 1184 people who individually evaluated the performance level of people in various scenes. Participants were excluded if the variance of their responses over the scenarios described in the questionnaire were too small or too big, i.e. a variance of two standard deviations greater or smaller than the average variance. That has been done in order to ensure that participants are not included if they probably did not intentionally relate to each of the scenarios (did not answer arbitrarily to the scenarios). All in all, thirty-six questionnaires were excluded. The final sample was comprised of 525 men and 620 women (3 missing cases), age range was 17–78 (average = 32.43, Standard Deviation = 11.27). The participants reported that they usually sleep 6.60 (Standard Deviation = 1.16) h/night. Of the participants 519 reported that during the past year they never consumed an alcoholic beverage in a manner that influenced their conscious or alertness, 303 stated that it happened once or twice and 320 reported three times or more. Participants were not asked whether they have a driver’s license or not, yet about 20% reported that during a regular week they drive 0 km or did not respond to this question. 2.2. Instruments The questionnaire (Appendix A) included 18 descriptions of imaginary situations (scenarios) where someone was asked to perform a duty under a certain awareness condition either after he/she has consumed alcohol or after restricted sleep. These scenarios were chosen out of a larger pool of scenarios that were suggested by twenty-six students who were asked to describe different situations where attentional resources are needed. The alcohol scenario related to BAC of 0.075% (201 participants). The restricted sleep scenarios referred to four different levels: (a) at 03:00 AM after being awake for 21 h (236 participants) (this item which describes prolonged wakefulness would hereby be related to as deprivation condition); (b) at 03:00 AM after waking from one hour of sleep (239 subjects); (c) at 03:00 AM after waking from four hours of sleep (262 subjects) and (d) at 03:00 AM after waking from six hours of sleep (210 participants). After each scenario the respondents had to rate the extent of fitness of the actor to complete the specific task posed in the scenario on a given scale of 0 (the lowest) to 100 (the highest). The questionnaire included a demographic section depicting sleep and drinking habits and estimation of mileage. 2.3. Procedure Each participant received a questionnaire with the 18 scenarios related to only one of the above mentioned conditions (alcohol consuming or one of the four levels of restricted sleep). After a brief explanation by the experimenter, each participant rated the degree of fitness of the described person in each item on a 0–100 scale. For the first condition (‘alcohol’ group, 201 respondents) the subjects were informed that in most European countries and in the U.S. driving is prohibited if the alcohol concentration in the blood reaches a level of between 0.05% and 0.1%. 3. Results 3.1. Collapsing scenarios into three factors A Factor Analysis procedure was carried out prior to computing the dependent variables. It revealed that the 18 scenarios depicted three distinct factors. We have actually run the Factor Analysis twice, first time for the entire sample and a second time had five parallel runs for each question/group. At the first run, over all 1148 participants, we identified three factors: the first factor had 10 scenarios grouped together (Lifesaving items), the second factor had three scenarios grouped together (Self-monitoring items) and the third factor depicted five scenarios (Success items). At the second time, with five parallel runs for each group we found that 10 scenarios can be grouped together to one factor 4 times out of the five runs. These were the same 10 scenarios that were grouped together in the former run as the Lifesaving items. Three other scenarios grouped together 4 times out of the five possible runs. These were the same 3 scenarios that were grouped together in
116
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123 Table 1 Division of the 18 scenarios to three factors. Loadings and internal consistency (Cronbach Alfa).
a b c
Life threateninga
Self-monitoringb
Competition/successc
Operation (.82) ER Doctor (.78) Officer (.76) Ambulance driver (.69) Sniper (.69) Pilot (.63) Fever (.62) Psychiatrist (.58) Policeman (.53) Forger (.50)
Hotel janitor (.81) Domino (.71) Haircut (.69)
Judo (.72) Telephone friend (.70) Tennis player (.67) CEO (.61) Boyfriend (.50)
Cronbach’s Alfa = .91. Cronbach’s Alfa = .73. Cronbach’s Alfa = .82.
Fig. 1. Weighted average and standard errors of estimated levels of performance relative to full capacity. Over-all differences between types of tasks (life threatening, self-monitoring and success) and conditions (Alcohol, sleep deprivation, sleep of one, four or six hours) are described in the text. Error bars indicate standard errors.
the former run as the Self-monitoring items. Two other scenarios that were initially in the Success factor grouped together again. Thus we had three identified factors and another three scenarios were less identifiable. We chose to combine the two scenarios with the three unidentified scenarios. This structure was both in accordance with the initial Factor Analysis run and reasonable as a ‘‘Success” factor. Following the results of the Factor Analysis we constructed three factors out of the 18 scenarios, according to their loadings (Varimax Rotation Analysis) as presented in Table 1. 3.2. Estimated performance levels under lowered awareness conditions The weighted average estimates of relative performance levels on the three factors under five conditions were calculated according to the loadings of each scenario and are presented in Fig. 1. More sleep was related to better expectation of performance level. Estimations of ability to perform a task after consuming alcohol varied among the factors. A repeated measures analysis of variance (ANOVA) with 3 5 (factors: Life threatening events, self-monitoring, success condition: Alcohol, sleep deprivation, one hour sleep, four our sleep, six hour sleep) revealed a main effect of difference between factors F(2,2236)1 = 53.08, p < .001, g2 = .05). The performance on life threatening events was rated as best and self-monitoring was rated the lowest, All p’s < .001. The between conditions (between subjects) main effect was significant F(1,1118) = 42.02, p < .001, g2 = .13). As can be seen in Fig. 1 our respondents considered the ability to perform the task after no sleep as more impaired than on other conditions. Alcohol came second, followed by performing after one hour of sleep, then 4 h and a person after 6 h of sleep was considered by our respondents as the most competent to perform the task. Type of task and condition of the actor interacted F(8,2236) = 32.01, p < .001 g2 = .10).
1 Twenty-five participants had occasional missing data witch distorted their weighted averages. The data of these participants were not included in this analysis.
117
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123 Table 2 Means (standard deviations) of the assessed performance levels in the various conditions by the different tasks.
N
Alcohol 201
No sleep 236
Sleep – 1 h 239
Sleep – 4 h 262
Sleep – 6 h 210
Transport
Ambulance driver Pilot Policeman Total
53.33 51.74 53.18 52.75
(25.03) (24.07) (22.40) (20.93)
56.70 (25.07) 43.77 (21.21) 48.71 (22.91) 49.73 (19.16)
64.45 54.39 59.54 59.41
(21.32) (23.34) (21.79) (17.30)
73.02 (19.37) 62.98 (21.80) 64.66 (20.09) 66.88 (15.59)
72.03 68.45 69.98 70.17
(18.51) (18.65) (18.48) (13.88)
Non-transport
Operation ER Doctor Officer Sniper Fever Psychiatrist Forger Hotel janitor Domino Haircut Judo Telephone friend Tennis player CEO Boyfriend Total
47.61 (24.42) 52.14 (23.45) 56.22 (25.25) 46.92 (24.85) 64.28 (23.95) 55.37 (23.24) 52.54 (21.96) 63.55 (22.28) 53.23 (21.45) 58.31 (22.30) 56.47 (22.49) 59.20 (22.75) 53.08 (22.50) 60.60 (22.51) 62.64 (23.51) 56.14 (17.96)
55.78 (23.09) 51.67 (22.27) 63.37 (23.79) 50.38 (23.88) 68.24 (21.93) 55.02 (22.32) 49.83 (22.16) 47.31 (21.70) 41.82 (21.18) 46.86 (20.68) 48.62 (22.63) 52.22 (23.25) 47.14 (21.88) 62.01 (23.10) 59.49 (23.43) 53.32 (15.09)
62.47 (22.36) 58.74 (22.02) 69.54 (20.63) 60.25 (22.45) 72.76 (20.19) 58.02 (20.70) 57.57 (22.71) 54.18 (24.38) 52.76 (22.77) 50.46 (22.29) 54.73 (22.51) 50.21 (22.94) 54.27 (21.44) 66.74 (20.83) 61.38 (22.59) 58.94 (13.15)
68.36 (21.23) 64.20 (23.24) 74.37 (21.22) 64.12 (22.64) 78.21 (19.30) 65.02 (20.20) 62.33 (22.27) 60.76 (22.83) 57.63 (21.98) 57.56 (19.79) 57.71 (21.34) 56.11 (20.40) 53.89 (22.68) 70.92 (19.88) 68.36 (21.95) 63.96 (13.52)
65.71 67.40 72.43 63.76 80.69 66.89 64.93 70.29 71.62 66.85 58.24 61.26 59.52 69.61 70.58 67.34
(19.83) (17.38) (19.54) (19.83) (16.82) (19.02) (19.30) (19.43) (18.44) (20.58) (20.92) (20.26) (22.16) (18.49) (20.57) (11.94)
Within the life threatening tasks the alcohol and sleep deprivation conditions did not differ and were significantly lower than each one of the sleep conditions. Ratings for performing after four or six hours of sleep did not differ. Within the selfmonitoring factor acting after alcohol consumption and sleeping four hours yielded the same level of expected performance. All other conditions were different. Within the success factor competing after sleep deprivation was significantly worse than after sleeping for four or six hours, while attempting to act after six hours of sleep was viewed as better than after alcohol, no sleep or one hour of sleep (Scheffe post hoc comparisons). 3.3. Transport vs. non-transport activities We further divided the original 18 scenarios into a group of transport activities and a group of non-transport activities as described in Table 2. The two activity types were related to the five awareness conditions: Alcohol, no-sleep, one, four and six hours of sleep. A (2 5) ANOVA (activity type condition) with repeated measures for transport vs. non-transport scenarios revealed both a main effect of condition F(4,1143) = 51.80, p < .001, g2 = .153 and an interaction effect of differences between the transport and non-transport scenarios with condition F(4,1143) = 20.29, p < .001, g2 = .07. Subsequent analysis of paired samples t-tests showed that, as can be seen in Fig. 2, while participants assessed that following both alcohol and no-sleep conditions transport tasks would be more impaired than non-transport tasks, t(200) = 4.76, p < .001; t(235) = 4.89,
Fig. 2. Assessed performance level of transport/non-transport tasks under five conditions. Differences between transport and non-transport activities according to the five conditions are described in the text. Error bars indicate standard errors.
118
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
p < .001 respectively, this tendency changed direction when more sleep was gained. After only one hour of sleep participants evaluated that there should be no difference between transport and non-transport activities, p < .05. However, after four hours of sleep and after six hours of sleep actors are thought to be more impaired for non-transport tasks as compared to transport tasks, t(261) = 5.117, p < .001 and t(209) = 3.78, p < .001, respectively. 3.4. Demographic variables With the exception of the alcohol condition, male and female respondents agreed on the ratings of expected performance levels on the three types of tasks. Only in the alcohol condition men consistently attributed a better competence of the actor than women’s expectations (Life threatening: t(199) = 4.12, p < .001; self-monitoring: t(199) = 3.24, p < .001; success: t(199) = 3.35, p < .001). These differences were still significant after an adjustment for multiple comparisons (A Bonferroni correction procedure). Other demographic variables as age, amount of reported habitual sleep hours, general experience of sleepiness, self-evaluation of knowledge about sleep or alcohol effects were not related to the estimation of actor’s ability while performing the tasks. Within the group of participants who responded to the alcohol condition there was no correlation between the number of heavy drinks in the past year and assessments of performance (Spearman’s rho p’s > .15). The correlations between the amount of kilometers (KM) habitually driven every week and the assessed performance level were non-significant or very weak, Life-threatening KM: r = .1, p < .01, Self-image X KM: r = NS, Success KM: r = .1, p < .01. 4. Discussion Perceptions held by people about the damages caused by fatigue and alcohol may affect their actual behavior (Williams et al., 2012). Therefore, we thought that perceptions of people towards the capability to perform various tasks (transportrelated and other tasks) under the influence of alcohol and in conditions of insufficient sleep are of importance. The purpose of this research was to examine how people estimate the ability to perform these specific tasks in various conditions of alcohol consuming and loss of sleep. Our first prediction was that laymen will assess that people that consumed alcohol will be less able to perform their task than those who were after sleep deprivation. We found that people considered the ability to perform various tasks after absolute sleep deprivation as more impaired than in other conditions. Alcohol came second, followed by performing in the other conditions. We were surprised to realize that contrary to the findings of Williams et al. (2012) our respondents were aware to the dangerous effect of full sleep deprivation for functioning in various tasks. To our knowledge, this perception fits the results of studies that compared the actual impairment of alcohol versus full sleep deprivation such as Dalawari and Scarbrough (2014). Furthermore, Arnedt et al. (2001) interpreted the behavior of the subjects who drove faster under the alcohol condition as compared to the prolonged wakefulness condition, as indicating either greater disinhibition following alcohol or better insight regarding the impairment due to prolonged wakefulness. On the other hand, our results do not have to be considered as contradicting those of Williams et al. (2012). We asked our participants about degree of capability while Williams et al. considered the amount of blame. As stated by Williams et al. subjects tend to blame the driver for driving after consuming alcohol at the same time that the circumstances are to be blamed for drowsy driving. Accordingly, it is possible that people rate sleep deprived drivers as less capable but blame them less than an alcoholic driver. Many efforts are invested in raising the public awareness of damages caused to safety by alcohol consumption (Buenaventura et al., 2014). Whether the distinction between assumed capability and blame is right or not, great efforts should be invested in raising the importance of sufficient sleep hours for maximizing the quality and safety of performance of various tasks. Our second prediction was that people will assess that performance is impaired as a function of the level of sleep loss i.e. the larger the deprivation the worse is the performance. Indeed, we found that more sleep was related to better expectation of performance level, right after the alcohol consuming condition (with the exception of absolute sleep loss that was perceived as the most damaging). It means that people perceived that the performance of the tasks will be the best after six hours of sleep, worse after four hours and the worst after one hour. As a matter of fact, this perception is realistic, since the damage caused to performance increases as sleep loss is higher (Goel, Rao, Durmer, & Dinges, 2009). However, this reference is only partial as the descriptions that were rated by the participants absolutely ignored the process of sleep inertia (Tassi & Muzet, 2000) and related solely to the duration of sleep. Future research should focus at this process as we know that sleep inertia plays a central role in functioning (Santhi et al., 2013; Tassi & Muzet, 2000). We also found that the type of task and condition of the actor interacted: Within the Alcohol condition the participants thought that engaging in a life threatening task will be more impaired than self-monitoring or seeking success. A different picture is attributed to the lost sleep conditions. The three conditions where a substantial amount of sleep is missed result in the same pattern of assessed ability to perform. In life threatening situations the actor can reach a higher performance level than in the success tasks followed by the self-monitoring tasks. For the last condition, six hours of sleep, the general ability is better and the pattern is different than the pattern of the other cases. There is ground to infer that in a cohort of people that sleep for 6.6 h/night with a standard deviation of 1.16 h, a need to perform after 6 h of sleep can be related to as ‘within nor-
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
119
mal limits’. The complex pattern of the results concerning the ability to perform the three types of tasks under the various conditions may reflect the misconception that people may hold about the extent that motivation can overcome the effects of sleep deprivation (Caruso & Hitchcock, 2010). When respondents related to the life threatening situations they might have believed that the actor can overcome some of the difficulty to function due to insufficient sleep but not due to alcohol. At the same time, in the case of self-monitoring, the outgoing nature of the effects of alcohol can explain the unique elevation of assessed ability at this point. Generally speaking, the results suggest that people imagine that an external drive to perform, such as when lives are at stake or winning becomes possible, can compete with an inner source of impairment, fatigue. However, an internal drive as self-monitoring is not enough for performing against fatigue. Following both alcohol and no-sleep conditions participants assessed that transport tasks would be more impaired than non-transport tasks. However, as sleep was gained participants evaluated that for transport tasks people would be less impaired as compared to non-transport tasks. Furthermore, following alcohol and no-sleep conditions participants assessed that transport and non-transport activities would be more impaired than after restricted sleep. This finding is in line with our general finding that people tend to evaluate alcohol and sleep deprivation as more impairing our functioning than restricted sleep. Gender differences were also found. Males and females agreed on the ratings of expected performance levels on the three types of tasks, except of in the alcohol condition where males attributed a better competence of the actor than females did. A possible explanation for this can stem from two origins: Males consume more alcohol than females (Randolph, Torres, GoreFelton, Lloyd, & McGarvey, 2009) and at the same time their self-efficacy is higher than females’ (Diseth, Meland, & Breidablik, 2014). It is notable that Oginska and Pokorski (2006) found that women reported a greater need for sleep and being more affected by chronic sleep loss than men. The lack of gender differences in relating to deficits caused by sleep loss in the current study may reflect either the fact that participants related to an actor rather to their self as in Oginska and Pokorski’s study, or that the interpretation of the outcomes of a single episode is not the same as to chronic sleep loss. However, the gender differences in the alcohol condition are in line with the results reported by Williams et al. (2012) that women place more blame than men on a driver who caused an accident after consuming alcohol or drowsy driving. One of the central findings of this research is that perception of the damage that may occur to performance interacts with the motivation for this task. When the task relates to life saving both alcohol and total sleep deprivations are perceived as the most damaging. This theoretical distinction is unique and can lead to further distinctions concerning motivation to perform a certain task. In the practical dimension, the findings of this research can provide useful information on the current recognition of sleepiness as a factor in accidents, and the need for education, especially for males. A limitation of the current research is related to the exclusion process of participants who were suspected to respond to the various scenarios arbitrarily, without actually considering each scenario. The statistical process we used may have identified some of these participants but not all of them. We could not identify those who chose to respond arbitrarily but not in an almost constant manner or at extremes. On the other hand, we may have wrongly excluded some who actually considered each scenario but resulted with very low or very high variance. Another limitation is related to the choice of scenarios presented to the participants. As Arnedt et al. (2001) pointed out concerning their study, the fact that the scenarios described in the current questionnaire mostly involved imagined actions of an actor who is mainly self-dependent and paced and free of any external involvement, may constitute an important difference between this self-report and reality. The assessed level of interference produced by alcohol or insufficient sleep may be different if the participants were to judge scenarios depicting interactive behavior. Further research can refer to a broader range of scenarios. Furthermore, the sampling of the current research was based on a convenience sampling method rather than on a representative sample. In light of this, we recommend that in a future study of the similar research question will be conducted by using a representative sample. The results presented here in combination with the results described by Williams et al. (2012) emphasize the importance of public awareness to the effects of lost sleep. Williams et al. found that people tend to blame a person who drove under the influence of alcohol more than they do so towards a sleep deprived driver. This distinction does not reflect lack of knowledge or misperceptions; rather, it is the conception people hold about it. We know now that people are aware of the detrimental effects of sleep deprivation on performance yet don’t relate to it as seriously. We assume that the law and publicity of the effects of alcohol helped in creating a concern and a social atmosphere over its potential dangers. Thus, it is time to call for legislators and professionals to campaign against drowsy driving.
120
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
Appendix A
1. Over the P.A. (Public Address) system of an airplane, the following question was heard: ‘‘Is there an airplane pilot among the passengers?” One of the passengers gets up and says that he is an experienced pilot. This announcement was made when the passenger ⁄_________________. Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
2. A student is planning to go out presently with a girl that had made a very good impression on him. Suddenly he remembers that his hair wasn’t properly cut. He asks his roommate to give him a haircut immediately. The roommate ⁄_________________ . Rate the performance level you think the roommate would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
3. An ambulance gets to an Emergency Room with a man in a very serious condition. When the patient arrived at the hospital the doctor that looks at him ⁄ ________________ . Rate the performance level you think the doctor would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
4. A young couple decide to invite their friends to ‘‘the best show in town.” To achieve this they lay out thousands of domino blocks side by side throughout their apartment. The hosts discover that they still have many blocks to place ⁄ ________________ . Rate the performance level you think the couple would have relative to their best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
5. A parent is noticing that his/her child is crying. The child’s fever has risen quite a lot, and the parent has to decide what would be the best treatment for the child. The parent ⁄ ________________ . Rate the performance level you think the parent would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
6. A tennis game is renewed after being halted due to rain that had fallen on the court. Your favorite player must serve the ball to his rival so as to win the match. Your favorite player ⁄ ________________ . Rate the performance level you think the player would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
7. An army post is hit by the enemy’s surprise attack. When the first shots are heard the officer in charge to deal with the situation ⁄ ________________ . Rate the performance level you think the officer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
8. A doctor has to perform a simple procedure which takes just a few moments. As the patient is being rolled into the operating theatre the doctor ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
9. A professional forger has to copy a foreign passport by hand. When he has to execute this task the forger ⁄ ________________ . Rate the performance level you think the forger would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
10. A psychiatrist is called to see a suicidal patient. Upon approaching the session the psychiatrist ⁄ ________________ . Rate the performance level you think the psychiatrist would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
121
11. In an international Judo competition the deciding round is five minutes long. Your country’s champion has to compete after he/she ⁄ ________________ . Rate the performance level you think the competitor would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
12. A soldier who is a trained sniper for long distance shots has to hit a distant target. The soldier ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
13. A hotel janitor has to clean up the lobby for honored guests after a sandstorm has completely dirtied the hall. He ⁄ ________________ . Rate the performance level you think the worker would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
14. A girl receives a phone call from her boyfriend who has severed their connections just two days ago. He is trying to decide whether or not to renew their relationship. The girl is very interested in restarting their affair, but she ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
15. An ambulance driver has to make a 30 min drive to get from the house of a man who just had a heart attack to the hospital. The driver knows the way, but ⁄ ________________ . Rate the performance level you think the driver would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
16. A traffic policeman is positioned to direct traffic at a busy intersection where the traffic lights are not operating. The policeman ⁄ _______________ . Rate the performance level you think the policeman would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
17. The CEO of a start-up company was negotiating the sale of his company for a fabulous sum, and had to give the final answer during a long-distance phone call. The CEO ⁄ ________________ . Rate the performance level you think the CEO would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
18. A competitor on a TV show decides to call a ‘‘telephone friend” to help him/her answer the last question for winning a large sum of money. When answering the phone the friend ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
122
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
References Arnedt, J. T., Wilde, G. J. S., Munt, P. W., & MacLean, A. W. (2001). How do prolonged wakefulness and alcohol compare in the decrements they produce on a simulated driving task? Accident Analysis and Prevention, 33, 337–344. Belenky, G., Wesensten, N. J., Thorne, D. R., Thomas, M. L., Sing, H. C., Redmond, D. P., ... Balkin, T. J. (2003). Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: A sleep dose response study. Journal of Sleep Research, 12, 1–12. Buenaventura, S. E., Jones, A., & Schramm, A. (2014). Sleep—not just beauty rest: An innovative approach to reducing healthcare worker fatigue. Nurse Leader, 12, 60–64. Campagne, A., Pebayle, T., & Muzet, A. (2004). Correlation between driving errors and vigilance levels: Influence of the driver’s age. Physiology and Behavior, 80, 515–524. Caruso, C. C., & Hitchcock, E. M. (2010). Strategies for nurses to prevent sleep-related injuries and errors. Rehabilitation Nursing, 35, 192–197. Chapman, C. D., Benedict, C., Brooks, S. J., & Schioth, H. B. (2012). Lifestyle determinants of the drive to eat: A meta-analysis. American Journal of Clinical Nutrition, 96, 492–497. Dalawari, P., & Scarbrough, M. L. (2014). Knowledge of alcohol impairment in boaters in Southern Illinois. The Journal of Emergency Medicine, 46, 567–571. Diseth, A., Meland, D. E., & Breidablik, H. J. (2014). Self-beliefs among students: Grade level and gender differences in self-esteem, self-efficacy and implicit theories of intelligence. Learning and Individual Differences, 1–8.
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
123
Fillmore, M. T. (2007). Acute alcohol-induced impairment of cognitive functions: Past and present findings. International Journal on Disability and Human Development, 6, 115–225. Goel, N., Rao, H., Durmer, J. S., & Dinges, D. F. (2009). Neurocognitive consequences of sleep deprivation. Seminars in Neurology, 29, 320–339. http://dx.doi. org/10.1055/s-0029-1237117. Howard, M. E., Melinda, L., Jackson, M. J., Berlowitz, D., O’Donoghue, F., Swann, P., Westlake, J., ... Pierce, R. J. (2014). Specific sleepiness symptoms are indicators of performance impairment during sleep deprivation. Accident Analysis & Prevention, 62, 1–8. International Bedroom Poll (2013). The National Sleep Foundation. Irwin, C., Leveritt, M., Shum, D., & Desbrow, B. (2013). The effects of dehydration, moderate alcohol consumption, and rehydration on cognitive functions. Alcohol, 47, 203–213. Jackson, M. L., Kennedy, G. A., Clarke, C., Gullo, M., Swann, P., Downey, L. A., ... Howard, M. E. (2016). The utility of automated measures of ocular metrics for detecting driver drowsiness during extended wakefulness. Accident Analysis & Prevention, 87, 127–133. Kolb, H., & Mandrup-Poulsen, T. (2010). The global diabetes epidemic as a consequence of lifestyle-induced low-grade inflammation. Diabetologia, 53, 10–20. Lamond, N., & Dawson, D. (1999). Quantifying the performance impairment associated with fatigue. Journal of Sleep Research, 8, 255–262. Lianzhen, W., & Yulong, P. (2014). The impact of continuous driving time and rest time on commercial drivers’ driving performance and recovery. Journal of Safety Research, 50, 11–15. Maistros, A., Schneider, W. H., & Savolainen, P. T. (2014). A comparison of contributing factors between alcohol related single vehicle motorcycle and car crashes. Journal of Safety Research, 49, 129–135. Maruff, P., Falleti, M. P., Collie, M. G., Darby, A., & McStephen, M. D. (2005). Fatigue related impairment in the speed, accuracy and variability of psychomotor performance: Comparison with blood alcohol levels. Journal of Sleep Research, 14, 7–21. McConnell, C. F., Bretz, K. M., & Dwyer, W. O. (2003). Falling asleep at the wheel: A close look at 1,269 fatal and serious injury-producing crashes. Behavioral Sleep Medicine, 1, 171–183. Miyata, S., Noda, A., Ozaki, N., Hara, Y., Minoshima, M., Iwamoto, K., ... Koike, Y. (2010). Insufficient sleep impairs driving performance and cognitive function. Neuroscience Letters, 469(2), 229–233. Moran, M., Baron-Epel, O., & Assi, N. (2010). Causes of road accidents as perceived by Arabs in Israel: A qualitative study. Transportation Research Part F, 13, 377–387. Moskowitz, H., & Fiorentino, D. (2000). A review of the literature on the effects of low doses of alcohol on driving-related skills (Technical report DOT HS 809 028). Washington, DC: National Highway Traffic Safety Administration. National Highway Traffic Safety Administration [NHTSA] (2012). Fatality analysis reporting system: Fatal crash trends; 2012http://www-fars.nhtsa.dot.gov/ Trends/TrendsGeneral.aspx. Accessed January 18, 2015. Oginska, H., & Pokorski, J. (2006). Fatigue and mood correlates of sleep length in three age-social groups: School children, students, and employees. Chronobiology International, 23, 1317–1328. doi:org.proxy1.athensams.net/10.1080/07420520601089349. Pilcher, J. J., & Huffcutt, A. (1996). Effects of sleep deprivation on performance: A meta-analysis: Specific sleepiness symptoms are indicators of performance impairment during sleep deprivation. Sleep, 19, 18–26. Randolph, M., Torres, H., Gore-Felton, C., Lloyd, B., & McGarvey, E. (2009). Alcohol use and sexual risk behavior among college students: Understanding gender and ethnic differences. American Journal of Drug Alcohol Abuse, 35, 80–84. Rosenbloom, T., Beigel, A., & Eldror, E. (2011). Attitudes, behavioral intentions, and risk perceptions of fatigued pedestrians. Social Behavior and Personality: An International Journal, 39(9), 1263–1270. Santhi, N., Groeger, J. A., Archer, S. N., Gimenez, M., Schlangen, L. J. M., & Dijk, D. J. (2013). Morning sleep inertia in alertness and performance: Effect of cognitive domain and white light conditions. PLoS ONE, 8, 79688. http://dx.doi.org/10.1371/journal.pone.0079688. Sotos, J. R., Gonzalez, A. L., Martínez, I. P., Rosa, M. C., Herraez, M. J. S., & Hidalgo, J. L. (2015). Self-assessment of alcohol consumption as a health-education strategy in nursing students. Nurse Education Today, 35, 132–137. http://dx.doi.org/10.1016/j.nedt.2014.08.004. Tassi, P., & Muzet, A. (2000). Sleep inertia. Sleep Medicine Reviews, 4, 341–353. Williams, L. R., Davies, D. R., Thiele, K., Davidson, J. R., & MacLean, A. W. (2012). Young drivers’ perceptions of culpability of sleep-deprived versus drinking drivers. Journal of Safety Research, 43, 115–122. Williamson, A. M., & Feyer, A. M. (2000). Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication. Occupational & Environmental Medicine, 57, 649–655. Yegneswaran, B., & Shapiro, C. (2007). Do sleep deprivation and alcohol have the same effects on psychomotor performance – Editorial. Journal of Psychosomatic Research, 63, 569–572.
Contents lists available at ScienceDirect
Transportation Research Part F journal homepage: www.elsevier.com/locate/trf
Perceived level of performance impairment caused by alcohol and restricted sleep Ephraim S. Grossman a,⇑, Tova Rosenbloom b a b
The Interdisciplinary Department of Social Sciences, Bar Ilan University, Ramat-Gan, Israel Management Department, Bar Ilan University, Ramat-Gan, Israel
a r t i c l e
i n f o
Article history: Received 20 January 2015 Received in revised form 25 April 2016 Accepted 1 June 2016
Keywords: Alcohol Sleep restriction Impairment Perception Assessment
a b s t r a c t The aim of the current study was to investigate people’s perceptions towards the ability to perform various tasks (transport-related and other tasks) under the influence of alcohol and prolonged wakefulness. We assumed that people will assess that after alcohol consumption performance is damaged more than after sleep restriction. In addition we assumed that participants will relate performance impairment to the level of sleep loss. Participants (525 men and 620 women) were asked to refer to eighteen descriptions of imaginary situations (scenarios) where someone was asked to perform a duty under a certain awareness condition either after alcohol consumption or after total or partial sleep restriction (four levels). Of the eighteen scenarios, three were related to transport safety such as ambulance driver, a traffic policeman and a pilot. Participants were asked to rate the degree of fitness of the described person in each scenario on a 0–100 scale. The results show that people considered the ability to perform various tasks after absolute sleep restriction as more impaired than in other conditions, with alcohol as second worse, followed by performing after the conditions of partial sleep restriction. Also, it has been found that more sleep was related to better performance. Within life threatening tasks, the alcohol and sleep restriction conditions did not differ in ratings and were significantly lower than each one of the sleep conditions. Furthermore, transportation activities were assessed as more impaired than non-transport activities after alcohol consumption and no sleep but less impaired than non-transport activities after restricted sleep. Ó 2016 Elsevier Ltd. All rights reserved.
1. Introduction More than half of the population in industrialized countries report insufficient sleep on a regular basis (International Bedroom Poll, 2013). There is evidence that biological functions such as memory consolidation and problem solving benefit from a restful night’s sleep (Chapman, Benedict, Brooks, & Schioth, 2012). On the other hand sleep deprivation has been correlated with different pathologies (Kolb & Mandrup-Poulsen, 2010) and a lot of evidence has accumulated about an association of sleep deprivation with expressions of impaired psychomotor performance (for example, Howard et al., 2014). Tasks that involve motor as well as cognitive skills are impaired by sleep deprivation (Pilcher & Huffcutt, 1996). One of the consequences of sleep deprivation is fatigue and it may cause all kinds of accidents, including road accidents
⇑ Corresponding author at: Interdisciplinary Department of Social Sciences, Bar-Ilan University, Gehha Rd., Ramat-Gan 52900, Israel. Tel.: +972 50 5654695; fax: +972 3 7384039. E-mail address: [email protected] (E.S. Grossman). http://dx.doi.org/10.1016/j.trf.2016.06.002 1369-8478/Ó 2016 Elsevier Ltd. All rights reserved.
114
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
(McConnell, Bretz, & Dwyer, 2003). Driving is a complex task that requires skills such as attention, rapid response time and perception of driving velocity. These skills may decrease due to fatigue states (Campagne, Pebayle, & Muzet, 2004) and thus may increase the probability of accidents (Lianzhen & Yulong, 2014). In line with this, Rosenbloom, Beigel, and Eldror (2011) found that after sleep deprivation pedestrians are not aware to the danger in road crossing. The current research refers to prolonged wakefulness and restricted sleep that mean wakefulness over a whole day or sleep of less than the recommended optimum amount of sleep of eight hours. However, in literature there is a clear indication that restricted sleep may cause deterioration in functioning even after the first night of sleep restriction similarly to sleep deprivation (Belenky et al., 2003). For example, driver drowsiness caused by sleep restriction is believed to be a leading cause of motor vehicle accidents throughout the world (Jackson et al., 2016). Furthermore, there is evidence that brake reaction time in a harsh-braking test was significantly longer after insufficient sleep than after sufficient sleep (Miyata et al., 2010). Another crucial contributor of accidents is alcohol consumption. Irwin, Leveritt, Shum, and Desbrow (2013) showed a detrimental impact of alcohol consumption on cognitive performance. Deterioration in performance following alcohol consumption has been shown on a range of cognitive tasks that includes concentrated and divided attention and choice reaction time (Moskowitz & Fiorentino, 2000), and response inhibition to stop-signal and go/no-go tasks (Fillmore, 2007). The required motor skills and balance needed for proper driving operation make drivers after consuming alcohol more prone to severe injuries, particularly motorcyclists that drive on curves (Maistros, Schneider, & Savolainen, 2014). This was seen by the motorcyclists making the improper maneuver, grabbing the front brake and losing control of the motorcycle due to braking while cornering. The combination of alcohol consumption and driving causes dangerous behavior and becomes a major risk factor in road accidents. Although driving may be perceived as an automatic, routine and elemental activity it is actually a motor activity requiring, among other abilities, a high level of concentration, keen eyesight, proper motor function, a good memory, and a sound decision-making process (Moran, Baron-Epel, & Assi, 2010). Any physical or emotional impairment may increase the risk of involvement in a road accident, or of committing a traffic offence (Rosenbloom et al., 2011). So, many alcohol-related crashes occur all over the world, for example in the United States (NHTSA, FARS, 2012). More specifically, in the US there are around 10,000 fatalities involving a blood alcohol concentration (BAC) above legal limits (Maistros et al., 2014). As described, alcohol and sleep restriction, as well as sleep deprivation are possible causes of deterioration of cognitive and motor functioning. Studies that compared the damages caused by both factors found that moderate levels of fatigue can produce decrements in performance equivalent to those produced by BAC levels determined by law to prohibit safe automobile operation (Arnedt, Wilde, Munt, & MacLean, 2001). They found similar influence of alcohol consumption and sleep deprivation on tracking and speed variability while driving. Yegneswaran and Shapiro (2007) refer in their review to the comparison between the damages caused by alcohol and sleep deprivation. On the basis of previous studies (Maruff, Falleti, Collie, Darby, & McStephen, 2005). Yegneswaran and Shapiro conclude that staying awake for 24 h leads to reduced hand-to-eye coordination, which is similar to having a blood alcohol concentration (BAC) of 0.08%. Furthermore, based on Lamond and Dawson (1999) and Williamson and Feyer (2000) they conclude that deterioration of cognitive function after 17 h of sustained wakefulness is equivalent to that observed with a BAC of 0.05% or higher. Contrary to the knowledge currently held by the scientific community, a recent study (Sotos et al., 2015) reveals that only a small proportion of students were familiar with the concept of ‘the hazardous drinker’, the limits deemed hazardous and, in particular, the quantification of alcohol consumption. Dalawari and Scarbrough (2014) examined the knowledge of nonexperts of the influence that alcohol consumption has on boating and revealed that less than 25% of the participants answered correctly four of the five knowledge questions that were posed to them. A similar finding has been demonstrated by Buenaventura, Jones, and Schramm (2014) referring to awareness to the damages caused by fatigue. Growing research evidence points out that healthcare worker fatigue negatively impacts quality of care, patient safety, and other functions. Worker fatigue has been shown to increase the risk for patient care errors and employee injuries. Yet, there is little employee awareness or knowledge of worker fatigue and its impact on quality, safety and the ability to function as a high-reliability organization (Buenaventura et al., 2014). While recent scientific evidence shows that driving of sleep-deprived drivers may be as dangerous as driving under the influence of alcohol (Dalawari & Scarbrough, 2014), this perception may not be held by laymen. Williams, Davies, Thiele, Davidson, and MacLean (2012) used qualitative as well as quantitative methods in an in-depth testing of young drivers’ perceptions towards drivers who were driving after sleep deprivation and under the influence of alcohol. They found that young drivers were more tolerant towards drowsy drivers than drunk drivers. The authors concluded that although driving while sleep-deprived is perceived by some as a dangerous activity, the degree of blame and responsibility placed on the driver is not nearly as high as it is for driving under the influence of alcohol. Williams et al. (2012) encouraged further research for better understanding of this misconception. The current study expands the range of activities that may be impaired by alcohol and sleep deprivation beyond driving to many other everyday life functions that are based on motor or cognitive tasks such as quiz solving, giving a haircut, handling a psychiatric patient, and operating an airplane. Also, the current study distinguishes between degrees of sleep loss compared to alcohol consumption and enlarges the sample to more than 1000 people. Unlike the previous study that examined young drivers the current study is based on participants with an age range of 17–78, most of them holding a driving license. The aim of the current study was to learn about people’s perceptions towards the ability to perform various transport-related tasks under
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
115
the influence of alcohol and prolonged wakefulness. In the current research we dealt with performance of transport-related tasks as well as to other different tasks that are based on motor and/or cognitive skills such as sports, decision making, giving a haircut etc. Based on the literature described above, we hypothesized that (a) laymen will assess that people that consumed alcohol will be less able to perform their task than those who were after restricted sleep and that (b) people will assess that performance will be impaired as a function of the level of sleep loss so that the larger the deprivation the worse is the performance. 2. Method 2.1. Participants The participants were voluntarily recruited by students of Social Sciences Studies that distributed the questionnaires among their social network. The research has been approved by the ethics committee of the department. The participants signed agreement consent. The initial sample included 1184 people who individually evaluated the performance level of people in various scenes. Participants were excluded if the variance of their responses over the scenarios described in the questionnaire were too small or too big, i.e. a variance of two standard deviations greater or smaller than the average variance. That has been done in order to ensure that participants are not included if they probably did not intentionally relate to each of the scenarios (did not answer arbitrarily to the scenarios). All in all, thirty-six questionnaires were excluded. The final sample was comprised of 525 men and 620 women (3 missing cases), age range was 17–78 (average = 32.43, Standard Deviation = 11.27). The participants reported that they usually sleep 6.60 (Standard Deviation = 1.16) h/night. Of the participants 519 reported that during the past year they never consumed an alcoholic beverage in a manner that influenced their conscious or alertness, 303 stated that it happened once or twice and 320 reported three times or more. Participants were not asked whether they have a driver’s license or not, yet about 20% reported that during a regular week they drive 0 km or did not respond to this question. 2.2. Instruments The questionnaire (Appendix A) included 18 descriptions of imaginary situations (scenarios) where someone was asked to perform a duty under a certain awareness condition either after he/she has consumed alcohol or after restricted sleep. These scenarios were chosen out of a larger pool of scenarios that were suggested by twenty-six students who were asked to describe different situations where attentional resources are needed. The alcohol scenario related to BAC of 0.075% (201 participants). The restricted sleep scenarios referred to four different levels: (a) at 03:00 AM after being awake for 21 h (236 participants) (this item which describes prolonged wakefulness would hereby be related to as deprivation condition); (b) at 03:00 AM after waking from one hour of sleep (239 subjects); (c) at 03:00 AM after waking from four hours of sleep (262 subjects) and (d) at 03:00 AM after waking from six hours of sleep (210 participants). After each scenario the respondents had to rate the extent of fitness of the actor to complete the specific task posed in the scenario on a given scale of 0 (the lowest) to 100 (the highest). The questionnaire included a demographic section depicting sleep and drinking habits and estimation of mileage. 2.3. Procedure Each participant received a questionnaire with the 18 scenarios related to only one of the above mentioned conditions (alcohol consuming or one of the four levels of restricted sleep). After a brief explanation by the experimenter, each participant rated the degree of fitness of the described person in each item on a 0–100 scale. For the first condition (‘alcohol’ group, 201 respondents) the subjects were informed that in most European countries and in the U.S. driving is prohibited if the alcohol concentration in the blood reaches a level of between 0.05% and 0.1%. 3. Results 3.1. Collapsing scenarios into three factors A Factor Analysis procedure was carried out prior to computing the dependent variables. It revealed that the 18 scenarios depicted three distinct factors. We have actually run the Factor Analysis twice, first time for the entire sample and a second time had five parallel runs for each question/group. At the first run, over all 1148 participants, we identified three factors: the first factor had 10 scenarios grouped together (Lifesaving items), the second factor had three scenarios grouped together (Self-monitoring items) and the third factor depicted five scenarios (Success items). At the second time, with five parallel runs for each group we found that 10 scenarios can be grouped together to one factor 4 times out of the five runs. These were the same 10 scenarios that were grouped together in the former run as the Lifesaving items. Three other scenarios grouped together 4 times out of the five possible runs. These were the same 3 scenarios that were grouped together in
116
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123 Table 1 Division of the 18 scenarios to three factors. Loadings and internal consistency (Cronbach Alfa).
a b c
Life threateninga
Self-monitoringb
Competition/successc
Operation (.82) ER Doctor (.78) Officer (.76) Ambulance driver (.69) Sniper (.69) Pilot (.63) Fever (.62) Psychiatrist (.58) Policeman (.53) Forger (.50)
Hotel janitor (.81) Domino (.71) Haircut (.69)
Judo (.72) Telephone friend (.70) Tennis player (.67) CEO (.61) Boyfriend (.50)
Cronbach’s Alfa = .91. Cronbach’s Alfa = .73. Cronbach’s Alfa = .82.
Fig. 1. Weighted average and standard errors of estimated levels of performance relative to full capacity. Over-all differences between types of tasks (life threatening, self-monitoring and success) and conditions (Alcohol, sleep deprivation, sleep of one, four or six hours) are described in the text. Error bars indicate standard errors.
the former run as the Self-monitoring items. Two other scenarios that were initially in the Success factor grouped together again. Thus we had three identified factors and another three scenarios were less identifiable. We chose to combine the two scenarios with the three unidentified scenarios. This structure was both in accordance with the initial Factor Analysis run and reasonable as a ‘‘Success” factor. Following the results of the Factor Analysis we constructed three factors out of the 18 scenarios, according to their loadings (Varimax Rotation Analysis) as presented in Table 1. 3.2. Estimated performance levels under lowered awareness conditions The weighted average estimates of relative performance levels on the three factors under five conditions were calculated according to the loadings of each scenario and are presented in Fig. 1. More sleep was related to better expectation of performance level. Estimations of ability to perform a task after consuming alcohol varied among the factors. A repeated measures analysis of variance (ANOVA) with 3 5 (factors: Life threatening events, self-monitoring, success condition: Alcohol, sleep deprivation, one hour sleep, four our sleep, six hour sleep) revealed a main effect of difference between factors F(2,2236)1 = 53.08, p < .001, g2 = .05). The performance on life threatening events was rated as best and self-monitoring was rated the lowest, All p’s < .001. The between conditions (between subjects) main effect was significant F(1,1118) = 42.02, p < .001, g2 = .13). As can be seen in Fig. 1 our respondents considered the ability to perform the task after no sleep as more impaired than on other conditions. Alcohol came second, followed by performing after one hour of sleep, then 4 h and a person after 6 h of sleep was considered by our respondents as the most competent to perform the task. Type of task and condition of the actor interacted F(8,2236) = 32.01, p < .001 g2 = .10).
1 Twenty-five participants had occasional missing data witch distorted their weighted averages. The data of these participants were not included in this analysis.
117
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123 Table 2 Means (standard deviations) of the assessed performance levels in the various conditions by the different tasks.
N
Alcohol 201
No sleep 236
Sleep – 1 h 239
Sleep – 4 h 262
Sleep – 6 h 210
Transport
Ambulance driver Pilot Policeman Total
53.33 51.74 53.18 52.75
(25.03) (24.07) (22.40) (20.93)
56.70 (25.07) 43.77 (21.21) 48.71 (22.91) 49.73 (19.16)
64.45 54.39 59.54 59.41
(21.32) (23.34) (21.79) (17.30)
73.02 (19.37) 62.98 (21.80) 64.66 (20.09) 66.88 (15.59)
72.03 68.45 69.98 70.17
(18.51) (18.65) (18.48) (13.88)
Non-transport
Operation ER Doctor Officer Sniper Fever Psychiatrist Forger Hotel janitor Domino Haircut Judo Telephone friend Tennis player CEO Boyfriend Total
47.61 (24.42) 52.14 (23.45) 56.22 (25.25) 46.92 (24.85) 64.28 (23.95) 55.37 (23.24) 52.54 (21.96) 63.55 (22.28) 53.23 (21.45) 58.31 (22.30) 56.47 (22.49) 59.20 (22.75) 53.08 (22.50) 60.60 (22.51) 62.64 (23.51) 56.14 (17.96)
55.78 (23.09) 51.67 (22.27) 63.37 (23.79) 50.38 (23.88) 68.24 (21.93) 55.02 (22.32) 49.83 (22.16) 47.31 (21.70) 41.82 (21.18) 46.86 (20.68) 48.62 (22.63) 52.22 (23.25) 47.14 (21.88) 62.01 (23.10) 59.49 (23.43) 53.32 (15.09)
62.47 (22.36) 58.74 (22.02) 69.54 (20.63) 60.25 (22.45) 72.76 (20.19) 58.02 (20.70) 57.57 (22.71) 54.18 (24.38) 52.76 (22.77) 50.46 (22.29) 54.73 (22.51) 50.21 (22.94) 54.27 (21.44) 66.74 (20.83) 61.38 (22.59) 58.94 (13.15)
68.36 (21.23) 64.20 (23.24) 74.37 (21.22) 64.12 (22.64) 78.21 (19.30) 65.02 (20.20) 62.33 (22.27) 60.76 (22.83) 57.63 (21.98) 57.56 (19.79) 57.71 (21.34) 56.11 (20.40) 53.89 (22.68) 70.92 (19.88) 68.36 (21.95) 63.96 (13.52)
65.71 67.40 72.43 63.76 80.69 66.89 64.93 70.29 71.62 66.85 58.24 61.26 59.52 69.61 70.58 67.34
(19.83) (17.38) (19.54) (19.83) (16.82) (19.02) (19.30) (19.43) (18.44) (20.58) (20.92) (20.26) (22.16) (18.49) (20.57) (11.94)
Within the life threatening tasks the alcohol and sleep deprivation conditions did not differ and were significantly lower than each one of the sleep conditions. Ratings for performing after four or six hours of sleep did not differ. Within the selfmonitoring factor acting after alcohol consumption and sleeping four hours yielded the same level of expected performance. All other conditions were different. Within the success factor competing after sleep deprivation was significantly worse than after sleeping for four or six hours, while attempting to act after six hours of sleep was viewed as better than after alcohol, no sleep or one hour of sleep (Scheffe post hoc comparisons). 3.3. Transport vs. non-transport activities We further divided the original 18 scenarios into a group of transport activities and a group of non-transport activities as described in Table 2. The two activity types were related to the five awareness conditions: Alcohol, no-sleep, one, four and six hours of sleep. A (2 5) ANOVA (activity type condition) with repeated measures for transport vs. non-transport scenarios revealed both a main effect of condition F(4,1143) = 51.80, p < .001, g2 = .153 and an interaction effect of differences between the transport and non-transport scenarios with condition F(4,1143) = 20.29, p < .001, g2 = .07. Subsequent analysis of paired samples t-tests showed that, as can be seen in Fig. 2, while participants assessed that following both alcohol and no-sleep conditions transport tasks would be more impaired than non-transport tasks, t(200) = 4.76, p < .001; t(235) = 4.89,
Fig. 2. Assessed performance level of transport/non-transport tasks under five conditions. Differences between transport and non-transport activities according to the five conditions are described in the text. Error bars indicate standard errors.
118
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
p < .001 respectively, this tendency changed direction when more sleep was gained. After only one hour of sleep participants evaluated that there should be no difference between transport and non-transport activities, p < .05. However, after four hours of sleep and after six hours of sleep actors are thought to be more impaired for non-transport tasks as compared to transport tasks, t(261) = 5.117, p < .001 and t(209) = 3.78, p < .001, respectively. 3.4. Demographic variables With the exception of the alcohol condition, male and female respondents agreed on the ratings of expected performance levels on the three types of tasks. Only in the alcohol condition men consistently attributed a better competence of the actor than women’s expectations (Life threatening: t(199) = 4.12, p < .001; self-monitoring: t(199) = 3.24, p < .001; success: t(199) = 3.35, p < .001). These differences were still significant after an adjustment for multiple comparisons (A Bonferroni correction procedure). Other demographic variables as age, amount of reported habitual sleep hours, general experience of sleepiness, self-evaluation of knowledge about sleep or alcohol effects were not related to the estimation of actor’s ability while performing the tasks. Within the group of participants who responded to the alcohol condition there was no correlation between the number of heavy drinks in the past year and assessments of performance (Spearman’s rho p’s > .15). The correlations between the amount of kilometers (KM) habitually driven every week and the assessed performance level were non-significant or very weak, Life-threatening KM: r = .1, p < .01, Self-image X KM: r = NS, Success KM: r = .1, p < .01. 4. Discussion Perceptions held by people about the damages caused by fatigue and alcohol may affect their actual behavior (Williams et al., 2012). Therefore, we thought that perceptions of people towards the capability to perform various tasks (transportrelated and other tasks) under the influence of alcohol and in conditions of insufficient sleep are of importance. The purpose of this research was to examine how people estimate the ability to perform these specific tasks in various conditions of alcohol consuming and loss of sleep. Our first prediction was that laymen will assess that people that consumed alcohol will be less able to perform their task than those who were after sleep deprivation. We found that people considered the ability to perform various tasks after absolute sleep deprivation as more impaired than in other conditions. Alcohol came second, followed by performing in the other conditions. We were surprised to realize that contrary to the findings of Williams et al. (2012) our respondents were aware to the dangerous effect of full sleep deprivation for functioning in various tasks. To our knowledge, this perception fits the results of studies that compared the actual impairment of alcohol versus full sleep deprivation such as Dalawari and Scarbrough (2014). Furthermore, Arnedt et al. (2001) interpreted the behavior of the subjects who drove faster under the alcohol condition as compared to the prolonged wakefulness condition, as indicating either greater disinhibition following alcohol or better insight regarding the impairment due to prolonged wakefulness. On the other hand, our results do not have to be considered as contradicting those of Williams et al. (2012). We asked our participants about degree of capability while Williams et al. considered the amount of blame. As stated by Williams et al. subjects tend to blame the driver for driving after consuming alcohol at the same time that the circumstances are to be blamed for drowsy driving. Accordingly, it is possible that people rate sleep deprived drivers as less capable but blame them less than an alcoholic driver. Many efforts are invested in raising the public awareness of damages caused to safety by alcohol consumption (Buenaventura et al., 2014). Whether the distinction between assumed capability and blame is right or not, great efforts should be invested in raising the importance of sufficient sleep hours for maximizing the quality and safety of performance of various tasks. Our second prediction was that people will assess that performance is impaired as a function of the level of sleep loss i.e. the larger the deprivation the worse is the performance. Indeed, we found that more sleep was related to better expectation of performance level, right after the alcohol consuming condition (with the exception of absolute sleep loss that was perceived as the most damaging). It means that people perceived that the performance of the tasks will be the best after six hours of sleep, worse after four hours and the worst after one hour. As a matter of fact, this perception is realistic, since the damage caused to performance increases as sleep loss is higher (Goel, Rao, Durmer, & Dinges, 2009). However, this reference is only partial as the descriptions that were rated by the participants absolutely ignored the process of sleep inertia (Tassi & Muzet, 2000) and related solely to the duration of sleep. Future research should focus at this process as we know that sleep inertia plays a central role in functioning (Santhi et al., 2013; Tassi & Muzet, 2000). We also found that the type of task and condition of the actor interacted: Within the Alcohol condition the participants thought that engaging in a life threatening task will be more impaired than self-monitoring or seeking success. A different picture is attributed to the lost sleep conditions. The three conditions where a substantial amount of sleep is missed result in the same pattern of assessed ability to perform. In life threatening situations the actor can reach a higher performance level than in the success tasks followed by the self-monitoring tasks. For the last condition, six hours of sleep, the general ability is better and the pattern is different than the pattern of the other cases. There is ground to infer that in a cohort of people that sleep for 6.6 h/night with a standard deviation of 1.16 h, a need to perform after 6 h of sleep can be related to as ‘within nor-
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
119
mal limits’. The complex pattern of the results concerning the ability to perform the three types of tasks under the various conditions may reflect the misconception that people may hold about the extent that motivation can overcome the effects of sleep deprivation (Caruso & Hitchcock, 2010). When respondents related to the life threatening situations they might have believed that the actor can overcome some of the difficulty to function due to insufficient sleep but not due to alcohol. At the same time, in the case of self-monitoring, the outgoing nature of the effects of alcohol can explain the unique elevation of assessed ability at this point. Generally speaking, the results suggest that people imagine that an external drive to perform, such as when lives are at stake or winning becomes possible, can compete with an inner source of impairment, fatigue. However, an internal drive as self-monitoring is not enough for performing against fatigue. Following both alcohol and no-sleep conditions participants assessed that transport tasks would be more impaired than non-transport tasks. However, as sleep was gained participants evaluated that for transport tasks people would be less impaired as compared to non-transport tasks. Furthermore, following alcohol and no-sleep conditions participants assessed that transport and non-transport activities would be more impaired than after restricted sleep. This finding is in line with our general finding that people tend to evaluate alcohol and sleep deprivation as more impairing our functioning than restricted sleep. Gender differences were also found. Males and females agreed on the ratings of expected performance levels on the three types of tasks, except of in the alcohol condition where males attributed a better competence of the actor than females did. A possible explanation for this can stem from two origins: Males consume more alcohol than females (Randolph, Torres, GoreFelton, Lloyd, & McGarvey, 2009) and at the same time their self-efficacy is higher than females’ (Diseth, Meland, & Breidablik, 2014). It is notable that Oginska and Pokorski (2006) found that women reported a greater need for sleep and being more affected by chronic sleep loss than men. The lack of gender differences in relating to deficits caused by sleep loss in the current study may reflect either the fact that participants related to an actor rather to their self as in Oginska and Pokorski’s study, or that the interpretation of the outcomes of a single episode is not the same as to chronic sleep loss. However, the gender differences in the alcohol condition are in line with the results reported by Williams et al. (2012) that women place more blame than men on a driver who caused an accident after consuming alcohol or drowsy driving. One of the central findings of this research is that perception of the damage that may occur to performance interacts with the motivation for this task. When the task relates to life saving both alcohol and total sleep deprivations are perceived as the most damaging. This theoretical distinction is unique and can lead to further distinctions concerning motivation to perform a certain task. In the practical dimension, the findings of this research can provide useful information on the current recognition of sleepiness as a factor in accidents, and the need for education, especially for males. A limitation of the current research is related to the exclusion process of participants who were suspected to respond to the various scenarios arbitrarily, without actually considering each scenario. The statistical process we used may have identified some of these participants but not all of them. We could not identify those who chose to respond arbitrarily but not in an almost constant manner or at extremes. On the other hand, we may have wrongly excluded some who actually considered each scenario but resulted with very low or very high variance. Another limitation is related to the choice of scenarios presented to the participants. As Arnedt et al. (2001) pointed out concerning their study, the fact that the scenarios described in the current questionnaire mostly involved imagined actions of an actor who is mainly self-dependent and paced and free of any external involvement, may constitute an important difference between this self-report and reality. The assessed level of interference produced by alcohol or insufficient sleep may be different if the participants were to judge scenarios depicting interactive behavior. Further research can refer to a broader range of scenarios. Furthermore, the sampling of the current research was based on a convenience sampling method rather than on a representative sample. In light of this, we recommend that in a future study of the similar research question will be conducted by using a representative sample. The results presented here in combination with the results described by Williams et al. (2012) emphasize the importance of public awareness to the effects of lost sleep. Williams et al. found that people tend to blame a person who drove under the influence of alcohol more than they do so towards a sleep deprived driver. This distinction does not reflect lack of knowledge or misperceptions; rather, it is the conception people hold about it. We know now that people are aware of the detrimental effects of sleep deprivation on performance yet don’t relate to it as seriously. We assume that the law and publicity of the effects of alcohol helped in creating a concern and a social atmosphere over its potential dangers. Thus, it is time to call for legislators and professionals to campaign against drowsy driving.
120
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
Appendix A
1. Over the P.A. (Public Address) system of an airplane, the following question was heard: ‘‘Is there an airplane pilot among the passengers?” One of the passengers gets up and says that he is an experienced pilot. This announcement was made when the passenger ⁄_________________. Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
2. A student is planning to go out presently with a girl that had made a very good impression on him. Suddenly he remembers that his hair wasn’t properly cut. He asks his roommate to give him a haircut immediately. The roommate ⁄_________________ . Rate the performance level you think the roommate would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
3. An ambulance gets to an Emergency Room with a man in a very serious condition. When the patient arrived at the hospital the doctor that looks at him ⁄ ________________ . Rate the performance level you think the doctor would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
4. A young couple decide to invite their friends to ‘‘the best show in town.” To achieve this they lay out thousands of domino blocks side by side throughout their apartment. The hosts discover that they still have many blocks to place ⁄ ________________ . Rate the performance level you think the couple would have relative to their best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
5. A parent is noticing that his/her child is crying. The child’s fever has risen quite a lot, and the parent has to decide what would be the best treatment for the child. The parent ⁄ ________________ . Rate the performance level you think the parent would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
6. A tennis game is renewed after being halted due to rain that had fallen on the court. Your favorite player must serve the ball to his rival so as to win the match. Your favorite player ⁄ ________________ . Rate the performance level you think the player would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
7. An army post is hit by the enemy’s surprise attack. When the first shots are heard the officer in charge to deal with the situation ⁄ ________________ . Rate the performance level you think the officer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
8. A doctor has to perform a simple procedure which takes just a few moments. As the patient is being rolled into the operating theatre the doctor ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
9. A professional forger has to copy a foreign passport by hand. When he has to execute this task the forger ⁄ ________________ . Rate the performance level you think the forger would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
10. A psychiatrist is called to see a suicidal patient. Upon approaching the session the psychiatrist ⁄ ________________ . Rate the performance level you think the psychiatrist would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
121
11. In an international Judo competition the deciding round is five minutes long. Your country’s champion has to compete after he/she ⁄ ________________ . Rate the performance level you think the competitor would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
12. A soldier who is a trained sniper for long distance shots has to hit a distant target. The soldier ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
13. A hotel janitor has to clean up the lobby for honored guests after a sandstorm has completely dirtied the hall. He ⁄ ________________ . Rate the performance level you think the worker would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
14. A girl receives a phone call from her boyfriend who has severed their connections just two days ago. He is trying to decide whether or not to renew their relationship. The girl is very interested in restarting their affair, but she ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
15. An ambulance driver has to make a 30 min drive to get from the house of a man who just had a heart attack to the hospital. The driver knows the way, but ⁄ ________________ . Rate the performance level you think the driver would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
16. A traffic policeman is positioned to direct traffic at a busy intersection where the traffic lights are not operating. The policeman ⁄ _______________ . Rate the performance level you think the policeman would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
17. The CEO of a start-up company was negotiating the sale of his company for a fabulous sum, and had to give the final answer during a long-distance phone call. The CEO ⁄ ________________ . Rate the performance level you think the CEO would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
18. A competitor on a TV show decides to call a ‘‘telephone friend” to help him/her answer the last question for winning a large sum of money. When answering the phone the friend ⁄ ________________ . Rate the performance level you think the volunteer would have relative to his/her best performance level.
10
Very Low
20
30
40
50
60
70
80
90
100
Full Capacity
122
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
References Arnedt, J. T., Wilde, G. J. S., Munt, P. W., & MacLean, A. W. (2001). How do prolonged wakefulness and alcohol compare in the decrements they produce on a simulated driving task? Accident Analysis and Prevention, 33, 337–344. Belenky, G., Wesensten, N. J., Thorne, D. R., Thomas, M. L., Sing, H. C., Redmond, D. P., ... Balkin, T. J. (2003). Patterns of performance degradation and restoration during sleep restriction and subsequent recovery: A sleep dose response study. Journal of Sleep Research, 12, 1–12. Buenaventura, S. E., Jones, A., & Schramm, A. (2014). Sleep—not just beauty rest: An innovative approach to reducing healthcare worker fatigue. Nurse Leader, 12, 60–64. Campagne, A., Pebayle, T., & Muzet, A. (2004). Correlation between driving errors and vigilance levels: Influence of the driver’s age. Physiology and Behavior, 80, 515–524. Caruso, C. C., & Hitchcock, E. M. (2010). Strategies for nurses to prevent sleep-related injuries and errors. Rehabilitation Nursing, 35, 192–197. Chapman, C. D., Benedict, C., Brooks, S. J., & Schioth, H. B. (2012). Lifestyle determinants of the drive to eat: A meta-analysis. American Journal of Clinical Nutrition, 96, 492–497. Dalawari, P., & Scarbrough, M. L. (2014). Knowledge of alcohol impairment in boaters in Southern Illinois. The Journal of Emergency Medicine, 46, 567–571. Diseth, A., Meland, D. E., & Breidablik, H. J. (2014). Self-beliefs among students: Grade level and gender differences in self-esteem, self-efficacy and implicit theories of intelligence. Learning and Individual Differences, 1–8.
E.S. Grossman, T. Rosenbloom / Transportation Research Part F 41 (2016) 113–123
123
Fillmore, M. T. (2007). Acute alcohol-induced impairment of cognitive functions: Past and present findings. International Journal on Disability and Human Development, 6, 115–225. Goel, N., Rao, H., Durmer, J. S., & Dinges, D. F. (2009). Neurocognitive consequences of sleep deprivation. Seminars in Neurology, 29, 320–339. http://dx.doi. org/10.1055/s-0029-1237117. Howard, M. E., Melinda, L., Jackson, M. J., Berlowitz, D., O’Donoghue, F., Swann, P., Westlake, J., ... Pierce, R. J. (2014). Specific sleepiness symptoms are indicators of performance impairment during sleep deprivation. Accident Analysis & Prevention, 62, 1–8. International Bedroom Poll (2013). The National Sleep Foundation. Irwin, C., Leveritt, M., Shum, D., & Desbrow, B. (2013). The effects of dehydration, moderate alcohol consumption, and rehydration on cognitive functions. Alcohol, 47, 203–213. Jackson, M. L., Kennedy, G. A., Clarke, C., Gullo, M., Swann, P., Downey, L. A., ... Howard, M. E. (2016). The utility of automated measures of ocular metrics for detecting driver drowsiness during extended wakefulness. Accident Analysis & Prevention, 87, 127–133. Kolb, H., & Mandrup-Poulsen, T. (2010). The global diabetes epidemic as a consequence of lifestyle-induced low-grade inflammation. Diabetologia, 53, 10–20. Lamond, N., & Dawson, D. (1999). Quantifying the performance impairment associated with fatigue. Journal of Sleep Research, 8, 255–262. Lianzhen, W., & Yulong, P. (2014). The impact of continuous driving time and rest time on commercial drivers’ driving performance and recovery. Journal of Safety Research, 50, 11–15. Maistros, A., Schneider, W. H., & Savolainen, P. T. (2014). A comparison of contributing factors between alcohol related single vehicle motorcycle and car crashes. Journal of Safety Research, 49, 129–135. Maruff, P., Falleti, M. P., Collie, M. G., Darby, A., & McStephen, M. D. (2005). Fatigue related impairment in the speed, accuracy and variability of psychomotor performance: Comparison with blood alcohol levels. Journal of Sleep Research, 14, 7–21. McConnell, C. F., Bretz, K. M., & Dwyer, W. O. (2003). Falling asleep at the wheel: A close look at 1,269 fatal and serious injury-producing crashes. Behavioral Sleep Medicine, 1, 171–183. Miyata, S., Noda, A., Ozaki, N., Hara, Y., Minoshima, M., Iwamoto, K., ... Koike, Y. (2010). Insufficient sleep impairs driving performance and cognitive function. Neuroscience Letters, 469(2), 229–233. Moran, M., Baron-Epel, O., & Assi, N. (2010). Causes of road accidents as perceived by Arabs in Israel: A qualitative study. Transportation Research Part F, 13, 377–387. Moskowitz, H., & Fiorentino, D. (2000). A review of the literature on the effects of low doses of alcohol on driving-related skills (Technical report DOT HS 809 028). Washington, DC: National Highway Traffic Safety Administration. National Highway Traffic Safety Administration [NHTSA] (2012). Fatality analysis reporting system: Fatal crash trends; 2012http://www-fars.nhtsa.dot.gov/ Trends/TrendsGeneral.aspx. Accessed January 18, 2015. Oginska, H., & Pokorski, J. (2006). Fatigue and mood correlates of sleep length in three age-social groups: School children, students, and employees. Chronobiology International, 23, 1317–1328. doi:org.proxy1.athensams.net/10.1080/07420520601089349. Pilcher, J. J., & Huffcutt, A. (1996). Effects of sleep deprivation on performance: A meta-analysis: Specific sleepiness symptoms are indicators of performance impairment during sleep deprivation. Sleep, 19, 18–26. Randolph, M., Torres, H., Gore-Felton, C., Lloyd, B., & McGarvey, E. (2009). Alcohol use and sexual risk behavior among college students: Understanding gender and ethnic differences. American Journal of Drug Alcohol Abuse, 35, 80–84. Rosenbloom, T., Beigel, A., & Eldror, E. (2011). Attitudes, behavioral intentions, and risk perceptions of fatigued pedestrians. Social Behavior and Personality: An International Journal, 39(9), 1263–1270. Santhi, N., Groeger, J. A., Archer, S. N., Gimenez, M., Schlangen, L. J. M., & Dijk, D. J. (2013). Morning sleep inertia in alertness and performance: Effect of cognitive domain and white light conditions. PLoS ONE, 8, 79688. http://dx.doi.org/10.1371/journal.pone.0079688. Sotos, J. R., Gonzalez, A. L., Martínez, I. P., Rosa, M. C., Herraez, M. J. S., & Hidalgo, J. L. (2015). Self-assessment of alcohol consumption as a health-education strategy in nursing students. Nurse Education Today, 35, 132–137. http://dx.doi.org/10.1016/j.nedt.2014.08.004. Tassi, P., & Muzet, A. (2000). Sleep inertia. Sleep Medicine Reviews, 4, 341–353. Williams, L. R., Davies, D. R., Thiele, K., Davidson, J. R., & MacLean, A. W. (2012). Young drivers’ perceptions of culpability of sleep-deprived versus drinking drivers. Journal of Safety Research, 43, 115–122. Williamson, A. M., & Feyer, A. M. (2000). Moderate sleep deprivation produces impairments in cognitive and motor performance equivalent to legally prescribed levels of alcohol intoxication. Occupational & Environmental Medicine, 57, 649–655. Yegneswaran, B., & Shapiro, C. (2007). Do sleep deprivation and alcohol have the same effects on psychomotor performance – Editorial. Journal of Psychosomatic Research, 63, 569–572.