Sleep behaviors in children with different frequencies of parental-reported sleep bruxism

Accepted Manuscript Title: Sleep behaviors in children with different frequencies of parental-reported sleep bruxism Authors: Claudia Restrepo, Daniele Manfredini, Frank Lobbezoo PII: DOI: Reference:

S0300-5712(17)30199-9 http://dx.doi.org/doi:10.1016/j.jdent.2017.08.005 JJOD 2819

To appear in:

Journal of Dentistry

Received date: Revised date: Accepted date:

26-6-2017 26-7-2017 6-8-2017

Please cite this article as: Restrepo Claudia, Manfredini Daniele, Lobbezoo Frank.Sleep behaviors in children with different frequencies of parental-reported sleep bruxism.Journal of Dentistry http://dx.doi.org/10.1016/j.jdent.2017.08.005 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Title: Sleep behaviors in children with different frequencies of parental-reported sleep bruxism Short title: Sleep behaviors and sleep bruxism in children

Claudia Restrepo Professor and Head CES-LPH Research Group Universidad CES. Calle 10 A No. 22-04. Medellín, Colombia. Daniele Manfredini Professor School of Dentistry Department of Neuroscience University of Padova Via 8 Febbraio 1848, 2, 35122 Padova, Italy. Frank Lobbezoo Professor, Chair, and Vice dean Department of Oral Health Sciences, Academic Centre for Dentistry Amsterdam (ACTA). University of Amsterdam and VU University, Amsterdam, The Netherlands Gustav Mahlerlaan 3004 | 1081 LA Amsterdam | The Netherlands Corresponding author Claudia Restrepo Calle 10 A No.22-04. Universidad CES. Medellín, Colombia. Tel: (57) 3108455592 e-mail: [email protected]

ABSTRACT Objective: Knowledge on the relationship between sleep bruxism (SB) and sleep behaviors in children is still fragmental, especially when socioeconomic factors are concerned. To assess sleep behaviors in children with different frequencies of proxy-reported SB. Methods: Parents of 1475 Colombian children, aged 9.8 ± 1.6 years, belonging to 3 different social layers, filled out a questionnaire on their children´s sleep (Children´s Sleep Habits Questionnaire [CSHQ]). Differences in sleep behaviors were assessed for the total sample and the three socioeconomic layers, using one-

way ANOVA and Bonferroni post-hoc tests or Kruskal-Wallis and Dunn’s post-hoc tests, based on the normality of outcome variables. Results: Most sleep patterns and daytime sleepiness were similar for children with different frequencies of proxy-reported SB, without differences among socioeconomic layers, whilst sleep disorders and parasomnias increased with the frequency of proxyreported SB, independently on the socioeconomic layer (Bonferroni post-hoc<0.001). The association between sleep-related habits and the frequency of proxy-reported SB was different for each socioeconomic layer. Conclusion: Among the various sleep behaviors under investigation, some sleep disorders and parasomnias seem to be associated with parental-reported SB in children. The influence of socioeconomic conditions on sleep behaviors seems not relevant. Based on these results, more specific studies on the association between different sleep behaviors are needed.

Keywords: sleep behaviors, sleep bruxism, children, sleep patterns, sleep disorders, parasomnias.

CLINICAL SIGNIFICANCE

Sleep behaviors, sociodemographic and socioeconomic features are correlated with SB in adults. However, in children, good evidence about this topic is lacking. This article give information to help clinicians evaluating sleep behaviors, sociodemographic and socioeconomic characteristics, when assessing sleep bruxism, based on evidence.

INTRODUCTION

Sleep bruxism (SB) is a repetitive jaw-muscle activity, characterized by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible [1], which is a common phenomenon in children [2]. Some sleep behaviors, such as snoring, mouth breathing, restless sleep, drooling, body position during sleep, and inadequate sleep time, have been identified as risk or associated factors for SB in children [3]. An adequate sleep time and quality is important for children’s health [Error! Bookmark not defined.], since it impacts behavioral and emotional functioning as well as learning skills and attention [4,5]. Sleep patterns are related to sleep time (bedtime, morning wakeup time, and daily

total sleep duration), which should theoretically warrant an adequate amount of sleep time in relation to the age of the subject [6,7]. In children, such patterns vary among individuals and are influenced by the time going to bed and the sleep-related habits (e.g., reading or watching TV before sleeping, and going to sleep in one’s own bed or in the parents’ or siblings´ bed). Alterations in sleep patterns and sleep-related habits could lead to sleep disorders ,[8,9], also based on the influence of psychological and social factors [10]. While a correlation of certain sleep behaviors with SB has been observed in children [,[11,12], information on the topic is still fragmental, especially as far as the possible influence of socioeconomic factors is concerned. Based on the above premises, the present study was performed in a sample of Colombian children belonging to different social layers, by adopting parental (“proxy”)-reported tooth grinding as an indicator of SB. The study was designed to test the hypotheses that: 1. sleep behaviors are different between children with different frequencies of proxy-reported SB; and 2. the association of proxy-reported SB with sleep behaviors if existing, is different among social layers.

MATERIALS AND METHODS

Study design Parents of Colombian children belonging to three different social layers filled out a dedicated questionnaire on sleep behaviors, viz., the Children’s Sleep Habits Questionnaire (CSHQ). An item on the report of sleep tooth grinding by the parents (“Does your child present grinding of the teeth during sleep?”) was assumed as the outcome variable, and it was referred to as “proxy-reported SB” in this investigation. Differences in sleep behaviors between children with different proxy-reported SB frequencies were explored in the total sample and in the three socioeconomic layers. The ethics committee at CES University gave the approval for the present study, and written informed consent was obtained for each participant. The study participants were 1500 parents of children that were randomly selected out of 155,849 potential 6-13 years old subjects, reported by the Colombian statistical system DANE (Departamento Administrativo Nacional de Estadísticas) and representative of the socioeconomic layers of the population of Medellin. Twenty-five children were excluded from the study because of their parents’ incomplete answers to the questionnaires, so that the final analysis was performed on a sample of 1475 individuals.

During meetings organized at schools, parents completed the Spanish version [13] of the Children’s Sleep Habits Questionnaire (CSHQ) [14] The CSHQ is a retrospective questionnaire, which recalls the child’s sleep behaviors over a “typical” recent week. The instrument consists of 40 items, which are rated on a 3-point frequency scale: 1 = “Rarely” if the sleep item occurs 0 or 1 time per week; 2 = “Sometimes” for 2 to 4 times per week; and 3 = “Usually” for 5 to 7 times per week. Items are grouped into 9 subscales/domains: “sleep patterns” (6 items), “bedtime resistance” (6 items), “sleep onset delay” (1 item), “sleep duration” (3 items), “sleep anxiety” (4 items), “night waking” (3 items), “sleep disordered breathing” (3 items), “parasomnias” (6 items), and “daytime sleepiness” (8 items). Domain subscores are the sum of items included in each subscale, while the total CSHQ score is the sum of all domain subscores. According to Buxton et al [15] and Owens et al [16], the 8 items evaluating sleep-related habits were not pertinent to a single domain. Specifically, they include five items belonging to the bedtime resistance domain (i.e., goes to bed at the same time, falls asleep in own bed, falls asleep in other’s bed, needs parents in room to sleep, struggles at bedtime), one item belonging to the daytime sleepiness domain (i.e., watches TV and/or other screens before going to bed), the item “sleeps the same amount each day” from the sleep duration domain, and the single item contained in the domain “falls asleep in 20 minutes”. The CSHQ has satisfactory psychometric properties in children [Error! Bookmark not defined.] and has been used in investigation on sleep in children [Error! Bookmark not defined.] and sleep tooth grinding in children [17]

Statistical analysis Descriptive analysis was performed to determine frequency distributions for categorical variables as well as mean values and measures of variation for quantitative variables. Kolmogorov-Smirnov test was used to evaluate normal distribution of values for each item, domain and total scores in the total sample, as well as in three different socioeconomic groups: low, medium, and high (www.dane.gov.co/files/geoestadistica; 2013). To assess the presence of differences in sleep behaviors between children with different proxy-reported SB frequency, one-way ANOVA with Bonferroni post-hoc or Kruskal-Wallis with Dunn´s post-hoc test were performed, based on the normality of the variables. The comparison between groups with different proxy-reported SB frequency was performed in the total sample as well as in the three different socioeconomic layers. For all statistical procedures, the level of significance was set at p<0.05. All data were analyzed with STATA© software version 13.0 (Copyright 1996–2016 StataCorp LP.TX.USA).

RESULTS

Prevalence of proxy-reported SB and CSHQ scores The sample consisted of 1475 children (718 girls and 757 boys, mean age 9.8 ± 1.6 years, range 613). SB was reported as “rarely” by the parents of 532 girls (74.2%) and 557 boys (73.6%); “sometimes” by the parents of 75 girls (10.4%) and 85 boys (11.2%); and “usually” by the parents of 111 girls (15.4%) and 115 boys (15.2%). The prevalence of proxy-reported SB with a frequency of two times or more per week (e.g., “sometimes” or “usually”) in the total study sample was 26.1% (table 1). The total CSHQ score was found to be significantly different between the proxy-reported SBfrequencies, both in the overall sample and in all the socioeconomic layers (table 2). In the sections below, sleep behaviors were reported separately as far as their prevalence in children with different frequency of SB is concerned.

Sleep patterns and proxy-reported SB Sleep patterns were evaluated with 6 items, corresponding to the “sleep patterns” CSHQ domain, which refers to bedtime, morning wakeup time, and daily total sleep duration during weekdays and weekends. Both in the total sample (table 2) and in the different socioeconomic layers (tables 3-5), sleep patterns were similar for children with a different frequency of proxy-reported SB. Independently on the social layer, children sleep a mean of 10.5 (SD 0.3) hours during weekends and less during weekdays [9.2 hours (SD 1 hour)]. A significant difference between groups with different proxyreported SB frequency was observed only for the variables “bedtime during weekends” in the medium socioeconomic layer (table 4) and “bedtime during weekdays” in the high socioeconomic layer (table 5). Post-hoc comparisons showed a significant difference for “bedtime during weekends” in the medium socioeconomic layer between “rarely”-“usually” proxy-reported SB (Dunn´s posthoc=0.04), and for “bedtime during weekdays” between “rarely”-“sometimes” proxy-reported SB (Dunn´s post-hoc=0.04).

Sleep-related habits and proxy-reported SB Concerning the sleep-related habits in the total sample, children with “usually” proxy-reported SB, fall asleep in own bed less frequently than those with “rarely”-reported SB. In addition, they also

report “falls asleep in 20 minutes”, “needs parents in room to sleep”, and “struggles at bedtime” more frequently during the week than children with “sometimes” and “rarely” proxy-reported SB. Differences between “rarely” and “usually” frequencies were statistically significant (Dunn’s posthoc<0.05)” (table 2). In the low socioeconomic layer, the items “goes to bed at the same time”, “falls asleep in 20 minutes”, and “watches TV and/or other screens before going to bed” showed significantly higher values for the “usually” proxy-reported SB than for the “rarely” frequency group (table 3). As for the medium socioeconomic layer, the items “goes to bed at the same time”, “needs parent in room to sleep”, and “struggles at bedtime” were significantly different among groups. Differences concerned mainly the comparison between children with “rarely” and “usually” reported SB (table 4). In the high socioeconomic layer, between-group significant differences concerned the items “falls asleep in own bed”, “needs parent in room to sleep”, and “struggles at bedtime” (table 5).

Sleep disorders, parasomnias and proxy-reported SB Sleep disorders were evaluated considering all items contained in the bedtime resistance, sleep onset delay, sleep duration, sleep anxiety, night waking, and sleep-disordered breathing subscales, whilst parasomnias were evaluated considering all items contained in the parasomnias subscale [Error! Bookmark not defined.]. As far as sleep disorders in the total sample are concerned, scores of the domains “sleep onset delay”, “sleep anxiety”, “night waking”, and “sleep disordered breathing”, as well as the score of “parasomnias” (, increased with the frequency of proxy-reported SB. For all the above domains, oneway ANOVA test for between-group differences was significant (p<0.05). When sleep disorders and “parasomnias” were analyzed separately in the different socioeconomic layers, the domain scores of “night waking” and “sleep disordered breathing” presented the same pattern as the total sample. Scores of such domains in the low, medium, and high socioeconomic layers increased significantly with the frequency of proxy-reported SB, except for “night waking” in the medium socioeconomic layer, which presents similar values for the “rarely” and “sometimes” frequencies. Differences were statistically significant for all between-group comparisons (Bonferroni post-hoc<0.05) (tables 3-5).

Daytime sleepiness and proxy-reported SB Daytime sleepiness was evaluated with all items contained in the daytime sleepiness subscale [Error! Bookmark not defined.], except for “watches TV and/or other screens before going to bed”.

Both in the total sample (table 2) and in the different socioeconomic layers (tables 3-5), the occurrence of daytime sleepiness was similar for children with a different frequency of proxyreported SB.

DISCUSSION

The adoption of regular sleep-related habits (i.e., behaviors before, during, and after sleep) and sleep patterns (bedtime, sleep duration and wake-up time) is useful to reduce the risk for sleep disorders [Error! Bookmark not defined.,Error! Bookmark not defined.]. So far, several studies on SB in children have addressed its relationship with sleep patterns and sleep disorders [Error! Bookmark not defined., 18,19,20,21] but not while taking the influence of socioeconomic conditions into consideration. Thus, this investigation aimed to assess if sleep behaviors were different between children with diverse frequencies of proxy-reported SB; and to determine if such differences vary among social layers. The main findings were that: 1. Sleep patterns were similar for children with different frequencies of proxy-reported SB, without any social layer-related differences; 2. Some sleep-related habits were different between children with different SB frequency, also varying within the three socioeconomic layers; and 3. Sleep disorders and parasomnias increased with the frequency of proxyreported SB, independently on the socioeconomic layers. As for findings on sleep patterns and SB, most available data refer to sleep duration, which is directly proportional to bedtime. Having a regular bedtime during early childhood has an important influence on children's behavior and prevention of sleep disorders [22] In this study, significant differences between children with different proxy-reported SB frequency were observed for “bedtime during weekends” in the medium socioeconomic layer and for “bedtime during weekdays” in the high socioeconomic layer. However, the reported sleep duration during weekends for all socioeconomic layers is in line with the time amount recommended in the literature for children aged between 8 and 12 years, which is between 10 and 12 hours per day [Error! Bookmark not defined.,23,24] and slightly less during weekdays [Mean 9.2 hours (SD 1 hour)]. Future studies on more selected samples, which may help reducing the risk of false-positive findings, are recommended to get deeper into these findings. The adequate children´s sleep duration reported by parents in all socioeconomic layers could be the reason for the lack of difference between the daytime sleepiness of children having different proxy-reported SB frequency. This is not in agreement with the results of a recent meta-analysis, which found a reduced sleep duration to be a risk factor for SB in childrenError! Bookmark not defined..

The relationship between sleep-related habits and proxy-reported SB in this study is inconsistent among socioeconomic layers. According to the parents’ report, the American Academy of Sleep Medicine recommendations for sleep-related habits [25] are not completely followed by the children taking part in the study. For instance, they do not fall asleep within 20 minutes, for at least 2-3 days of the week. A healthy sleep onset time should be between 5 and 30 minutes [Error! Bookmark not defined.], which means that children in this study do not have an adequate sleep onset for about half of the week. However, “sleep onset delay” was only associated with proxy-reported SB in the low socioeconomic layer. To our knowledge, this is the first study to report that sleep onset delay is found to be associated with proxy-reported SB in children from low-income families. Regarding the use of screens during bedtime, proxy-reported SB was related to screen time before sleep, even if only in children of the medium layer. This is in line with the results of the study by Peiró-Velert et al [26] Even when differences were found for sleep-related habits among frequencies of SB in the three socioeconomic layers, sleep patterns of children were not affected. This observation is not in agreement with a recent study, showing that parent´s habits related to bedtime affect sleep duration and quality in their children [27] In this investigation, it was observed that there are significant differences in the prevalence of sleep disorders (sleep anxiety, night waking, and sleep disordered breathing) and parasomnias between children with different SB frequency. This finding is in accordance with data that have been used

to

refine

the

International

Classification

of

Sleep

Disorders

(http://www.esst.org/adds/ICSD.pdf). Sleep disorders have been previously related to SB in children, as assessed with parental report of sleep tooth grinding [Error! Bookmark not defined.,Error! Bookmark not defined.]. More specifically, snoring, mouth breathing, and restless sleep have been described as risk or associated factors for SB in childrenError! Bookmark not defined., which is in agreement with the results of this investigation. The interpretation of findings from this investigation are limited by the lack of a definite quantification of sleep behaviors, which could be achieved with polysomnography (PSG). High economical costs, limited availability, complex technical equipment as well as the unfamiliar laboratory setting and difficulties to use it in children, are limits to the use of PSG for routine purposes [28], but its adoption to support suggestions from studies on possible SB is recommended for future investigations. Additionally, it should be noticed that an investigation on sleep behaviors could be affected by the socioeconomic disparities, regarding nutrition, health care, and education of children and

their

parents

among

the

three

socioeconomic

layers

in

Colombia

(https://data.unicef.org/country/col/). For instance, habits like sleeping with the parents in single-

bedroom houses may influence any parental reports, and are suggested to be studied in future investigations. Other features that could affect sleep behavior of Colombian children, such as academic stress in the high socioeconomic layer,[30],or even violence and/or abuses in the low socioeconomic layer [31,32] are to be considered in future investigations. However, since both sleep patterns and disorders as well as parasomnias were found to be similar in all socioeconomic layers, data from this investigation suggest that those shortcomings did not influence the study of their relationship with SB in Colombian children.

CONCLUSION Among the various sleep behaviors under investigation, some sleep disorders and parasomnias seem to be associated with parental-reported SB in children. The influence of socioeconomic conditions on sleep behaviors seems not relevant. Based on these results, more specific studies on the association between different sleep behaviors are needed.

DECLARATION OF INTEREST The authors declared no conflict of interest.

ACKKNOWLEDGEMENT This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. The investigation was fully financed by Universidad CES.

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27 K.E Patrick, G Millet, J.A Mindell, Sleep Differences by Race in Preschool Children: The Roles of Parenting Behaviors and Socioeconomic Status, Behav Sleep Med. 14 (2016) 467-479. 28 M.J Thorpy, Classification of sleep disorders, Neurotherapeutics. 9 (2012) 687-701. 29 R.N Aurora, C.I Lamm, R.S Zak, D.A Kristo, S.R Bista, J.A Rowley, Practice parameters for the non-respiratory indications for polysomnography and multiple sleep latency testing for children, Sleep. 35 (2012) 1467-1473. 30 H Westerlund, K Rajaleid, P Virtanen, PE Gustafsson, T Nummi, A Hammarström, Parental academic involvement in adolescence as predictor of mental health trajectories over the life course: a prospective population-based cohort study, BMC Public Health. 15 (2015) 653. 31 S.L Gaviria, R.D Alarcón, M Espinola, D Restrepo, J Lotero, DY Berbesi, GM Sierra, R Chaskel, Z Espinel, JM Shultz, Socio-demographic patterns of posttraumatic stress disorder in Medellin, Colombia and the context of lifetime trauma exposure, Disaster Health. 3 (2016) 139-150. 32 R Assaad, G Friedemann-Sánchez, D Levison, Impact of Domestic Violence on

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Table 1. Demographics and socioeconomics characteristics

Rarely

Proxy-reported sleep bruxism Sometimes Usually

Total

Gender (N, %): Female Male

532 (74.1) 557 (73.5)

75 (10.4) 85 (11.2)

111 (15.4) 115 (15.2)

718(100) 757 (100)

9.9 ± 1.6 8 (8, 11) 6 - 13

9.5 ± 1.6 9.5 (8, 11) 7 - 12

9.5 ± 1.7 7.5 (8, 11) 6 – 13

9.8 ± 1.6 10 (8, 11) 6 - 13

Lowest Medium Highest

178 (68.4) 509 (74.4) 402 (75.4)

26 (10) 86 (12.5) 48 (9.0)

56 (21.5) 87 (13.2) 83 (15.5)

260 (100) 682 (100) 533 (100)

Place of birth of the parents (N, %): Medellín Out of Medellín

650 (73.7) 439 (74.0)

97 (11.0) 63 (10.6)

135 (15.3) 91 (15.3)

882 (100) 593 (100)

953 (74.5) 136 (69.3)

134 (10.5) 25 (12.7)

191 (14.9) 35 (17.8)

1278 (100) 196 (100)

1089 (73.8)

160 (10.8)

226 (15.3)

1475 (100)

Age (years): Mean ± SD Median (Q1, Q3) Min - max Socioeconomic status (N, %):

Zone of birth of the parents (N, %): Urban Rural Total (N, %):

Table 2. Sleep behaviors, total and domain scores and proxy-reported bruxism. Variance (Kruskal-Wallis and one-way ANOVA) and p value in the total sample. Proxy-reported sleep bruxism

F

p value

Post-Hoc Test p-value

SLEEP PATTERNS Bedtime during weekdays (mean, sd) Morning wakeup time during weekdays (mean, sd) Daily total sleep duration during weekdays (mean, sd) Bedtime during weekends (mean, sd) Morning wakeup time during weekends (mean, sd) Daily total sleep duration during weekends (mean, sd)

Rarely 20:42 (3:00) 6:32 (1:27) 9.3 (1.5) 19:26 (7:05) 8:54 (1:18) 10.6 (1.3)

Sometimes 20:30 (4:00) 6:37 (1:40) 9.2 (1.5) 20:26 (4:09) 8:59(1:22) 10.5 (1.2)

Usually 20:50 (2:36) 6:26 (1:26) 9.3 (1.5) 20:04 (6:19) 8:54 (1:17) 10.6 (1.3)

0.6 0.8 0.7 2.5 0.3 0.3

0.57 0.47 0.50 0.08 0.73 0.73

-

BEDTIME RESISTANCE (MEAN, SD): Goes to bed at the same time Falls asleep in own bed Falls asleep in other’s bed Needs parent in room to sleep Struggles at bedtime Afraid of sleeping alone

7.35 (2.0) 1.92 (0.9) 1.27 (0.6) 1.8 (0.68) 1.27 (0.6) 1.34 (0.6) 2.03 (0.2)

7.45 (1.9) 1.91 (0.9) 1.24 (0.5) 1.43 (0.67) 1.32 (0.7) 1.41 (0.6) 2.09 (0.3)

7.60 (2.1) 2.0(0.9) 1.12 (0.4) 1.42 (0.92) 1.41 (0.7) 1.54 (0.8) 2.08 (0.3)

1.5 0.8 5.6 0.5 4.3 9.4 0.7

0.22 0.46 0.004 0.58 0.01 p<0.001 0.56

0.002 (Rarely-Usually) + 0.01 (Rarely-Usually) + 0.002 (Rarely-Usually) + -

SLEEP ONSET DELAY (MEAN, SD): Falls asleep in 20 minutes

1.99 (1.0) 1.99 (1.0)

2.17 (0.9) 2.16 (1.0)

2.12 (0.9) 2.12 (1.0)

3.1 3.1

0.04 0.04

* *

SLEEP DURATION (MEAN, SD): Sleeps too Little Sleeps the right amount Sleeps same amount each day

5.88 (0.9) 1.17 (0.55) 2.83 (0.5) 1.88 (1.2)

5.90 (0.90) 1.14 (0.5) 2.86 (0.5) 1.90 (1.1)

5.92 (0.9) 1.22 (0.63) 2.78 (0.6) 1.92 (1.2)

0.2 1.2 1.2 0.7

0.85 0.29 0.29 0.85

-

SLEEP ANXIETY (MEAN, SD): Needs parent in room to sleep Afraid of sleeping in the dark Afraid of sleeping alone Trouble sleeping away

2.78 (1.2) 1.27 (0.6) 1.34 (0.67) 2.03 (0.2) 1.05 (0.30)

2.92 (1.24) 1.32 (0.7) 1.47 (0.75) 2.09 (0.3) 1.06 (0.31)

3.10 (1.4) 1.41 (0.7) 1.63 (0.83) 2.08 (0.3) 1.12 (0.43)

6.5 4.4 12.3 0.7 4.1

0.002 0.01 p<0.001 0.56 0.01

p<0.001 (Rarely-Usually) + 0.01 (Rarely-Usually) + * 0.01 ((Rarely-Usually) +

NIGHT WAKINGS (MEAN, SD):

3.38 (1.1)

3.55 (1.1)

4.03 (1.6)

28.6

p<0.001

Moves to other’s bed during night

1.18 (0.53)

1.35 (0.56)

1.51 (0.82)

28.6

p<0.001

Awakes once during night

1.18 (0.53)

1.25 (0.56)

1.51 (0.82)

28.6

p<0.001

Awakes more than once

1.01 (0.17)

1.04 (0.27)

1.02 (0.19)

1.0

0.35

SLEEP DISORDERED BREATHING (MEAN, SD):

3.46 (1.0)

3.8 (1.1)

4.34 (1.4)

60.8

p<0.001

Snores loudly

1.27 (0.6)

1.44 (0.6)

1.86 (0.9)

69.2

p<0.001

Stops breathing

1.19 (0.4)

1.36 (0.5)

1.48 (0.5)

45.7

0.02

Snorts and gasps

1.0 (0.0)

1.0 (0.0)

1.0 (0.0)

-

-

PARASOMNIAS (MEAN, SD):

8.24 (1.5)

9.72 (1.6)

11.89 (2.9)

404.3

p<0.001

Wets the bed during night

1.00 (0.0)

1.00 (0.0)

0.1 (0.1)

2.7

0.06

Talks during sleep

1.05 (0.2)

1.10 (0.3)

1.27 (0.6)

40.9

p<0.001

Restless and moves a lot

1.87 (0.9)

2.15 (0.8)

2.41 (0.8)

36.8

p<0.001

Sleep walks

1.18 (0.5)

1.26 (0.6)

1.51 (0.8)

28.6

p<0.001

Awakens screaming, sweating

1. 07 (0.3)

1.11 (0.3)

1.42 (0.8)

67.3

p<0.001

++ p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) ++ p<0.001 (Rarely-Usually) 0.01 (Rarely-Sometimes) p<0.001 (Sometimes-Usually) + 0.01 (Rarely-Usually) p<0.001 (Rarely-Sometimes) p<0.001 (Sometimes-Usually) + 0.01 (Rarely-Usually) p<0.001 (Rarely-Sometimes) 0.03 (Sometimes-Usually) ++ p<0.001 (Rarely-Usually) p<0.001 (Rarely-Sometimes) p<0.001 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + 0.02 (Rarely-Usually) 0.02 (Rarely-Sometimes) 0.01 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) +

Alarmed by scary dream

1.07 (0.3)

1.10 (0.3)

1.27 (0.8)

27.4

p<0.001

DAYTIME SLEEPINESS (MEAN, SD): Wakes by himself/ herself Wakes up in negative mood Others wake child Hard time getting out of bed Takes long time to be alert Seems tired Watches tv and/or other screens before going to bed Riding in car

11.75 (1.9) 2.1 (0.9) 1.72 (0.9) 1.20 (0.6) 1.20 (0.6) 1.01 (0.1) 1.12 (0.4) 2.03 (0.9) 1.41 (0.7)

11.68 (2.0) 2.0 (0.9) 1.60 (0.8) 1.20 (0.5) 1.20 (0.5) 1.02 (0.1) 1.63 (0.4) 2.05 (0.8) 1.46 (0.72)

12.0(2.1) 2.0 (0.9) 1.70 (0.9) 0.56 (0.7) 1.28 (0.6) 1.01 (0.1) 1.19 (0.4) 2.2 (0.9) 1.36 (0.71)

2.4 0.6 1.4 2.3 1.9 0.6 2.9 2.7 0.9

0.09 0.56 0.32 0.10 0.15 0.56 0.05 0.06 0.42

TOTAL SCORE (MEAN, SD):

43.32 (5.3)

45.67 (5.9)

49.4 1 (7.2)

109.3

p<0.001

-Not applicable. * Not significant. +Dunn´s post-hoc test. ++ Bonferroni post-hoc test.

p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) * p<0.001 (Rarely-Usually) p<0.001 (Rarely-Sometimes) p<0.001 (Sometimes-Usually)

Table 3. Sleep behaviors, total and domain scores, and proxy-reported bruxism. Variance (one-way ANOVA and Kruskal-Wallis) and p value in the low socioeconomic layer.

Proxy-reported sleep bruxism

F

p value

Dunn’s Post-Hoc Test p-value

SLEEP PATTERNS Bedtime during weekdays (Mean, SD) Morning wakeup time during weekdays (Mean, SD) Daily total sleep duration during weekdays (Mean, SD) Bedtime during weekends (Mean, SD) Morning wakeup time during weekends (Mean, SD) Daily total sleep duration during weekends (Mean, SD)

Rarely 21:00 (1:50) 6:25 (1:25) 9.2 (1.4) 20:11 (6:07) 8:44 (1:11) 10.5 (1.2)

Sometimes 21:30 (0:50) 6:23 (1:35) 9.0 (1.7) 20:46 (8:08) 8:51 (1:20) 10.4 (0.9)

Usually 20:42 (2:54) 6:16 (1:17) 9.1 (1.2) 19:46 (6:56) 8:46 (1:14) 10.4 (1.1)

1.2 0.2 0.5 0.6 0.1 1.1

0.30 0.80 0.58 0.56 0.90 0.86

-

BEDTIME RESISTANCE (MEAN, SD): Goes to bed at the same time Falls asleep in own bed Falls asleep in other’s bed Needs parent in room to sleep Struggles at bedtime Afraid of sleeping alone

7.0 (2.9) 1.8 (0.9) 1.18 (0.5) 1.29 (0.6) 1.24 (0.6) 1.32 (0.7) 1.18 (0.5)

7.1 (1.4) 1.8 (1.0) 1.07 (0.3) 1.34(0.56) 1.44 (0.7) 1.31 (0.62) 1.1 (0.3)

7.07(1.7) 2.2 (1.0) 1.05 (0.3) 1.32 (0.63) 1.18 (0.6) 1.30 (0.6) 1.1 (0.3)

0.1 5.0 1.9 0.1 1.5 0.0 -

0.93 0.007 0.15 0.86 0.22 0.98 -

0.05 (Rarely-Usually)+ -

SLEEP ONSET DELAY (MEAN, SD): Falls asleep in 20 minutes

1.83 (1.0) 1.83 (1.0)

2.0 (1.0) 2.0 (1.0)

2.30 (0.9) 2.30 (0.9)

5.0 5.0

0.008 0.008

0.006 (Rarely-Usually) + 0.006 (Rarely-Usually) +

SLEEP DURATION (MEAN, SD): Sleeps too little Sleeps the right amount Sleeps same amount each day

5.88 (1.0) 1.21 (0.6) 2.78 (6.2) 1.87 (1.0)

6.0 (1.0) 1.1 (0.4) 2.92 (0.4) 1.92 (1.0)

6.1 (1.0) 1.1 (0.4) 2.89 (0.4) 2.08 (0.9)

1.1 1.2 1.2 1.1

0.34 0.30 0.30 0.34

-

SLEEP ANXIETY (MEAN, SD): Needs parent in room to sleep Afraid of sleeping in the dark Afraid of sleeping alone Trouble sleeping away

2.7 (1.1) 1.24 (0.6) 1.30 (0.6) 1.18 (0.5) 1.06 (0.3)

2.8 (1.2) 1.44 (0.7) 1.3 (0.7) 1.1 (0.3) 1.07 (0.39)

2.6 (1.2) 1.18 (0.6) 1.4 (0.8) 1.1 (0.3) 1.16 (0.49)

0.3 1.5 1.0 1.7

0.73 0.22 0.40 1.0

-

NIGHT WAKINGS (MEAN, SD):

3.4 (1.1)

3.6 (1.2)

5.0 (2.0)

24.7

p<0.001

Moves to other’s bed during night

1.18 (0.5)

1.3 (0.6)

1.9 (0.1)

25.7

p<0.001

Awakes once during night

1.18 (0.5)

1.3 (0.6)

1.9 (0.1)

25.2

p<0.001

Awakes more than once

1.01 (0.0)

1.0 (0.0)

1.0 (0.0)

0.2

0.79

SLEEP DISORDERED BREATHING (MEAN, SD):

3.3 (1.0)

3.8 (1.1)

5.0 (1.4)

39.2

p<0.001

Snores loudly

1.10 (0.5)

1.47 (1.0)

2.1 (1.0)

40.7

p<0.001

Stops breathing

1.1 (0.3)

1.42 (0.5)

1.60 (0.5)

35.6

p<0.001

Snorts and gasps

1.0 (0.0)

1.0 (0.0)

1.0 (0.0)

-

-

PARASOMNIAS (MEAN, SD):

8.1 (1 .4)

9.8 (1.8)

13.3 (4.0)

112.1

p<0.001

Wets the bed during night

1.0 (0.0)

1.0 (0.0)

1.0 (0.0)

-

-

Talks during sleep

1.03 (0.2)

1.07 (0.3)

1.60 (0.1)

34.8

0.04

Restless and moves a lot

1.84 (1.0)

2.15 (0.9)

2.43 (0.1)

8.1

p<0.001

Sleep walks

1.20 (0.5)

1.31 (0.6)

1.91 (1.0)

25.2

0.03

Awakens screaming, sweating

1.04 (0.25)

1.15 (0.46)

1.86 (1.0)

50.0

p<0.001

Alarmed by scary dream

1.06 (0.3)

1.1 (0.32)

1.6 (1.0)

24.1

0.04

++ p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) ++ 0.02 (Rarely-Sometimes) p<0.001 (Rarely-Usually) 0.003 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + p<0.001 (Rarely-Sometimes) p<0.001 (Rarely-Usually) ++ 0.002 (Rarely-Sometimes) p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + 0.03 (Rarely-Usually) 0.03 (Sometimes-Usually) p<0.001 (Rarely-Usually) + + 0.03 (Rarely-Sometimes) 0.01 (Sometimes-Usually) + p<0.001 (Rarely-Usually) p<0.001 (Sometimes-Usually) + 0.03 (Rarely-Usually) 0.04 (Sometimes-Usually)

DAYTIME SLEEPINESS (MEAN, SD): Wakes by himself/ herself Wakes up in negative mood Others wake child Hard time getting out of bed Takes long time to be alert Seems tired Watches TV and/or other screens before going to bed Riding in car

11.4 (1.6) 2.1 (1.0) 1.64 (1.0) 1.16 (0.5) 1.15 (0.5) 1.0 (0.0) 1.1 (0.3) 1.98 (0.89) 1.3 (0.6)

11.4 (2.2) 2.2 (1.0) 1.34 (0.6) 1.15 (0.5) 1.15 (0.5) 1.0 (0.0) 1.2 (0.5) 1.96 (0.91) 1.40 (0.7)

11.8 (1.9) 2.1 (1.0) 1.46 (0.7) 1.2 (0.6) 1.2 (0.6) 1.1 (0.1) 1.1 (0.25) 2.41 (0.85) 1.30 (0.6)

0.7 0.2 2.3 0.1 0.7 1.8 2.2 5.1 0.2

0.48 0.85 0.11 0.92 0.50 0.16 0.10 0.006 0.81

TOTAL SCORE (MEAN, SD):

42.1 (5.0)

45.1 (5.0)

51.4 (9.0)

50.4

0.001

-Not applicable. * Not significant. +Dunn´s post-hoc test. ++ Bonferroni post-hoc test.

0.006 (Rarely-Usually) + p<0.001 (Rarely-Usually) 0.003 (Someitmes-Usually) +

Table 4. Sleep behaviors, total and domain scores and proxy-reported bruxism. Variance (one-way ANOVA and Kruskal-Wallis) and p value in the medium socioeconomic layer Proxy-reported sleep bruxism

F

p value

Dunn’s Post-Hoc Test p-value

SLEEP PATTERNS Bedtime during weekdays (Mean, SD) Morning wakeup time during weekdays (Mean, SD) Daily total sleep duration during weekdays (Mean, SD) Bedtime during weekends (Mean, SD) Morning wakeup time during weekends (Mean, SD) Daily total sleep duration during weekends (Mean, SD)

Rarely 20:12 (4:07) 6:28 (1:26) 9.3 (1.5) 20:40 (7:50) 9:00 (1:20) 10.6 (1.3)

Sometimes 20:05 (4:55) 6:40 (1:38) 9.1 (0.5) 22:16 (8:58) 9:03 (1:23) 10.4 (1.3)

Usually 21:05 (1:00) 6:20 (1:22) 9.2 (1.3) 20:13 (5:53) 8:55 (1:25) 10.7 (1.3)

1.9 1.2 0.5 3.1 0.2 1.2

0.14 0.28 0.58 0.04 0.82 0.31

0.04 (Rarely-Usually) + -

BEDTIME RESISTANCE (MEAN, SD): Goes to bed at the same time Falls asleep in own bed Falls asleep in other’s bed Needs parent in room to sleep Struggles at bedtime Afraid of sleeping alone

7.4 (2.0) 1.89 (0.9) 1.30 (0.6) 1.40 (0.70) 1.28 (0.64) 1.34 (0.63) 2.06 (0.2)

7.0 (1.7) 1.77 (0.9) 1.17 (0.5) 1.34 (0.61) 1.19 (0.54) 1.42 (0.64) 2.0 (0.001)

7.3 (1.7) 1.64 (0.8) 1.13 (0.61) 1.41 (1.17) 1.43 (0.74) 1.53 (0.74) 2.14 (0.4)

1.1 3.3 0.4 0.3 3.1 3.6 0.6

0.32 0.04 0.20 0.73 0.04 0.03 0.6

0.05 (Rarely-Usually) + 0.04 (Rarely-Usually)+ 0.04 (Sometimes-Usually) + 0.03 (Rarely-Usually) + -

SLEEP ONSET DELAY (MEAN, SD): Falls asleep in 20 minutes

1.93 (1.0) 1.93 (1.0)

2.01 (1.0) 2.01 (1.0)

1.85 (1.0) 1.85 (1.0)

0.6 0.6

0.6 0.6

-

SLEEP DURATION (MEAN, SD): Sleeps too little Sleeps the right amount Sleeps same amount each day

6.0 (0.9) 1.81 (0.6) 2.82 (0.6) 1.86 (0.90)

5.7 (0.9) 1.21 (0.6) 2.80 (0.6) 1.73 (0.9)

6.0 (0.9) 1.27 (0.7) 2.72 (0.7) 1.56 (0.8)

4.3 1.0 1.0 1.0

0.01 0.4 0.4 0.01

0.01 (Rarely-Usually) + 0.01 (Rarely-Usually) +

SLEEP ANXIETY (MEAN, SD):

2.8 (1.17)

2.7 (1.1)

3.2 (1.5)

5.2

0.006

Needs parent in room to sleep

1.28 (0.6)

1.19 (0.5)

1.43 (0.7)

3.1

0.04

Afraid of sleeping in the dark

1.32 (0.6)

1.4 (0.7)

1.6 (0.8)

8.0

p<0.001

Afraid of sleeping alone Trouble sleeping away

2.06 (0.2) 1.06 (0.3)

2.0 (0.001) 1.02 (0.1)

2.14 (0.4) 1.11 (0.4)

0.6 2.0

0.6 0.14

NIGHT WAKINGS (MEAN, SD):

3.3 (1.0)

3.3 (0.8)

3.7 (1.4)

4.8

0.008

Moves to other’s bed during night

1.2 (0.5)

1.1 (0.3)

1.3 (0.7)

5.7

0.03

Awakes once during night

1.2 (0.5)

1.1 (0.3)

1.3 (0.7)

5.7

0.03

Awakes more than once

1.0 (0.1)

1.1 (0.4)

1.0 (0.0)

4.0

0.02

SLEEP DISORDERED BREATHING (MEAN, SD):

3.4 (1.0)

3.8 (1.1)

4.2 (1.4)

20.0

p<0.001

Snores loudly

1.3 (0.6)

1.4 (0.7)

1.8 (0.9)

22.6

p<0.001

Stops breathing

1.2 (0.4)

1.4 (0.5)

1.4 (0.5)

14.9

p<0.001

Snorts and gasps

1.0 (0.0)

1.0 (0.0)

1.0 (0.0)

-

-

PARASOMNIAS (MEAN, SD):

8.1 (1.4)

9.4 (1.4)

11.4 (2.4)

177.0

p<0.001

Wets the bed during night

1.0 (0.0)

1.0 (0.0)

1.0 (0.1)

3.4

0.03

Talks during sleep

1.04 (0.2)

1.1 (0.3)

1.2 (0.5)

8.4

p<0.001

Restless and moves a lot

1.8 (0.9)

2.1 (0.8)

2.4 (0.8)

18.1

p<0.001

Sleep walks

1.2 (0.5)

1.1 (0.3)

1.3 (0.7)

5.7

0.003

++ 0.007 (Rarely-Usually) 0.02 (Sometimes-Usually) 0.04 (Sometimes-Usually) + + p<0.001 (Rarely-Usually) 0.03 (Sometimes-Usually) ++ 0.007 ((Rarely-Usually) 0.04 (Sometimes-Usually) + 0.05 (Rarely-Usually) 0.01 (Sometimes-Usually) + 0.05 (Rarely-Usually) 0.01 (Sometimes-Usually) + 0.02 (Rarely-Usually) 0.04 (Sometimes-Usually) ++ 0.02 (Rarely-Usually) p<0.001 (Rarely-Sometimes) 0.04 (Sometimes-Usually) + p<0.001 (Rarely-Usually) 0.004 (Sometimes-Usually) +0.006 (Rarely-Sometimes) p<0.001 (Rarely-Usually) 0.006 (Rarely-Usually) ++p<0.001 (Rarely-Usually) p<0.001 (Rarely.Sometimes) p<0.001 (Sometimes-Usually) 0.03 (Rarely-Usually) + +p<0.001 (Rarely-Usually) 0.05 (Sometimes-Usually) +0.01 (Rarely-Usually) 0.02 (Rarely-Sometimes) p<0.001 (Sometimes-Usually) +0.05 (Rarely-Usually) 0.01 (Sometimes-Usually)

Awakens screaming, sweating

1.1 (0.2)

1.1 (0.3)

1.3 (0.7)

20.4

p<0.001

Alarmed by scary dream

1.1 (0.3)

1.1 (0.5)

1.2 (0.5)

4.1

0.02

DAYTIME SLEEPINESS (MEAN, SD): Wakes by himself/ herself Wakes up in negative mood Others wake child Hard time getting out of bed Takes long time to be alert Seems tired Watches TV and/or other screens before going to bed Riding in car

11.9 (2.0) 2.0 (1.0) 1.8 (0.9) 1.2 (0.6) 1.2 (0.6) 1.0 (0.1) 1,1 (0.4) 2.0 (1.0) 1.4 (0.7)

11.5 (1.7) 1.9 (1.0) 1.7 (0.9) 1.2 (0.6) 1.2 (0.6) 1.0 (0.1) 1.1 (0.3) 2.0 (1.0) 1.4 (0.7)

12.0 (2.1) 1.9 (0.9) 1.9 (1.1) 1.3 (0.7) 1.3 (0.7) 1.0 (0.0) 1.2 (0.4) 2.0 (1.0) 1.4 (0.8)

1.8 0.8 1.2 1.5 0.4 0.3 1.1 0.1 0.1

0.2 0.43 0.32 0.23 0.67 0.71 0.32 0.86 0.99

TOTAL SCORE (MEAN, SD):

43.2 (5.2)

44.0 (5.0)

47.5 (7.0)

23.5

p<0.001

-Not applicable. * Not significant. +Dunn´s post-hoc test. ++ Bonferroni post-hoc test.

+0.03 (Rarely-Usually) 0.04 (Sometimes-Usually) 0.01 (Rarely-Usually)+ ++p<0.001 (Rarely-Usually)s p<0.001 (Sometimes-Usually)

Table 5. Sleep behaviors, total and domain scores and proxy-reported bruxism. Variance (one-way ANOVA and Kruskal-Wallis) and p value in the high socioeconomic layer.

F

p value

Dunn’s Post-Hoc Test pvalue

Usually 20:39(3:25) 6:41 (1:33) 9.4 (1.6) 20:07 (6:24) 8:58 (1:12) 10.5 (1.2)

4.0 0.0 0.0 0.0 0.3 0.1

0.02 0.96 1.00 1.00 0.74 0.85

0.02 (Rarely-Sometimes) -

Proxy-reported sleep bruxism SLEEP PATTERNS Rarely Sometimes Bedtime during weekdays (Mean, SD) 21:11 (00:56) 20:43 (3:01) Morning wakeup time during weekdays (Mean, SD) 6:39 (1:30) 6:42 (1:42) Daily total sleep duration during weekdays (Mean, SD) 9.5 (1.5) 9.5 (1.6) Bedtime during weekends (Mean, SD) 20:07 (6:19) 20:19 (6:09) Morning wakeup time during weekends (Mean, SD) 8:52 (1:17) 8:58 (1:22) -Not applicable. * Not significant. +Dunn´s post-hoc test. ++ Bonferroni post-hoc test. Daily total sleep duration during weekends (Mean, SD) 10.6 (1.2) 10.6 (1.3)

BEDTIME RESISTANCE (MEAN, SD):

7.4 (1.9)

8.4 (2.2)

8.3 (2.1)

9.5

p<0.001

Goes to bed at the same time Falls asleep in own bed Falls asleep in other’s bed Needs parent in room to sleep Struggles at bedtime Afraid of sleeping alone

2.0 (0.9) 1.5 (0.7) 1.4 (0.7) 1.3 (0.6) 1.4 (0.6) 2.0 (0.0)

2.2 (0.8) 1.2 (0.5) 1.6 (0.8) 1.5 (0.8) 1.5 (0.7) 2.0 (0.0)

2.2 (0.9) 1.3 (0.6) 1.5 (0.8) 0.6 (1.0) 1.7 (0.8) 2.0 (0.0)

2.2 3.1 3.1 7.3 10.6 -

0.10 0.04 0.05 p<0.001 p<0.001 -

++0.006 (Rarely-Sometimes) 0.002 (Rarely-Usually) 0.04 (Sometimes-Usually) + * 0.002 (Rarely-Usually) + p<0.001 (Rarely-Usually) + -

SLEEP ONSET DELAY (MEAN, SD): Falls asleep in 20 minutes

2.1 (1.0) 2.1 (1.0)

2.5 (0.8) 2.5 (0.8)

2.3 (0.9) 2.3 (0.9)

3.6 3.6

0.03 0.03

0.03 (Rarely-Sometimes) + 0.03 (Rarely-Sometimes) +

SLEEP DURATION (MEAN, SD): Sleeps too little Sleeps the right amount Sleeps same amount each day

5.9 (0.9) 1.1 (0.5) 2.9 (0.5) 1.9 (1.0)

6.2 (0.8) 1.0 (0.3) 3.0 (0.3) 2.2 (0.8)

6.2 (0.9) 1.2 (0.6) 3.0 (0.6) 2.2 (0.9)

4.1 2.9 2.9 4.1

0.02 0.05 0.05 0.02

SLEEP ANXIETY (MEAN, SD):

2.8 (1.2)

3.3 (1.4)

3.3 (1.6)

7.2

p<0.001

Needs parent in room to sleep

1.3 (0.6)

1.5 (0.8)

0.6 (1.0)

7.3

p<0.001

Afraid of sleeping in the dark

1.4 (0.7)

1.7 (0.9)

1.7 (0.9)

4.1

0.02

Afraid of sleeping alone Trouble sleeping away

2.0 (0.0) 1.0 (0.3)

2.0 (0.0) 1.1 (0.4)

2.0 (0.0) 1.1 (0.4)

1.8

0.2

Night wakings (Mean, SD):

3.4 (1.1)

4.0 (1.5)

3.9 (1.5)

6.5

0.002

Moves to other’s bed during night

1.2 (0.5)

1.5 (0.7)

1.4 (0.8)

0.9

0.002

Awakes once during night

1.0 (0.2)

1.0 (0.0)

1.9 (0.3)

6.3

0.002

Awakes more than once

1.0 (0.2)

1.0 (0.0)

1.0 (0.3)

0.9

0.4

* * * * ++0.006 (Rarely-Usually) 0.03 (Rarely-Sometimes) +0.002 (Rarely-Usually) 0.03 (Rarely-Sometimes) +0.02 (Rarely-Sometimes) 0.01 (Rarely-Usually) * ++0.02 (Rarely-Sometimes) 0.02 (Sometimes-Usually) +0.02 (Rarely-Sometimes) 0.003 (Rarely-Usually) +0.02 (Rarely-Sometimes) 0.03 (Rarely-Usually) -

SLEEP DISORDERED BREATHING (MEAN, SD):

3.5 (1.2)

3.7 (1.0)

4.2 (1.4)

12.3

p<0.001

Snores loudly

1.3 (0.7)

1.4 (0.6)

1.8 (0.7)

14.4

p<0.001

Stops breathing Snorts and gasps

1.2 (0.5) 1.0 (0.0)

1.3 (0.5) 1.0 (0.0)

1.5 (0.5) 1.0 (0.0)

9.0 -

p<0.001 -

PARASOMNIAS (MEAN, SD):

8.4(1.6)

10.2 (1.8)

11.4 (2.1)

113.6

p<0.001

Wets the bed during night Talks during sleep Restless and moves a lot

1.0 (0.0) 1.0 (2.9) 1.9 (0.9)

1.0 (0.0) 1.1 (0.4) 2.2 (0.7

1.0 (0.0) 1.2 (0.4) 2.4 (0.8)

3.7 10.4

0.03 0.001

Sleep walks

1.2 (0.5)

1.5 (0.7)

1.4 (0.8)

6.3

0.002

Awakens screaming, sweating Alarmed by scary dream

1.1 (0.4) 1.1 (0.3)

1.1 (0.4) 1.2 (0.4)

0.6 (0.1) 1.1 (0.4)

4.9 3.1

0.008 0.04

DAYTIME SLEEPINESS (MEAN, SD): Wakes by himself/ herself Wakes up in negative mood Others wake child Hard time getting out of bed Takes long time to be alert Seems tired Watches TV and/or other screens before going to bed Riding in car

11.7 (1.9) 2.1 (0.9) 1.7 (0.8) 1.2 (0.5) 1.2 (0.5) 1.0 (0.1) 1.1 (0.4) 2.1 (0.9) 1.4 (0.7)

12.1 (2.2) 2.0 (0.9) 1.6 (0.8) 1.2 (0.5) 1.2 (0.5) 1.0 (0.3) 1.3 (0.6) 2.2 (0.9) 1.5 (0.7)

12.2 (2.2) 2.1 (0.9) 1.6 (0.9) 1.3 (0.7) 1.3 (0.7) 1.0 (0.2) 1.3 (0.6) 2.2 (0.9) 1.3 (0.7)

3.1 0.5 0.0 2.0 1.9 0.9 6.2 1.5 1.2

0.04 0.60 0.90 0.10 0.15 0.37 0.002 0.2 0.34

TOTAL SCORE (MEAN, SD):

44.0 (5.6)

48.9 (6.5)

50.1 (5.7)

49.1

p<0.001

p<0.001 (Rarely-Usually) ++ +p<0.001 (Rarely-Usually) 0.01 (Sometimes-Usually) p<0.001 (Rarely-Usually) + ++p<0.001 (RarelySometimes) p<0.001 (RarelyUsually) p<0.001 (SometimesUsually) * 0.001 (Rarely-Usually) + +0.02 (Rarely-Sometimes) 0.03 (Rarely-Sometimes) +0.005 (Rarely-Usually) * * * ++ p<0.001 (RarelySometimes) p<0.001 (RarelyUsually)