- Email: [email protected]
Vocal Symptoms, Voice Activity, and Participation Profile and Professional Performance of Call Center Operators
Vocal Symptoms, Voice Activity, and Participation Profile and Professional Performance of Call Center Operators *Tatiana Carvalho Piwowarczyk, *Gisele Oliveira, †Luciana Lourenc¸o, and *Mara Behlau, *ySao Paulo, Brazil Summary: Purpose. To analyze the phonatory and laryngopharyngeal symptoms reported by call center operators; and quantify the impact of these symptoms on quality of life, and the association between these issues and professional performance, number of monthly calls, and number of missed workdays. Methods. Call center operators (n ¼ 157) from a billing call center completed the Vocal Signs and Symptoms Questionnaire and the Brazilian version of the Voice Activity and Participation Profile (VAPP). The company provided data regarding professional performance, average number of monthly calls, and number of missed workdays for each employee. Results. The mean number of current symptoms (6.8) was greater in the operators than data for the general population (1.7). On average, 4.2 symptoms were attributed to occupational factors. The average number of symptoms did not correlate with professional performance (P ¼ 0.571). However, fewer symptoms correlated with decreased missed workdays and higher mean monthly call figures. The VAPP scores were relatively low, suggesting little impact of voice difficulties on call center operator’s quality of life. However, subjects with elevated VAPP scores also had poorer professional performance. Conclusions. The presence of vocal symptoms does not necessarily relate to decreased professional performance. However, an association between higher vocal activity limitation and participation scores and poorer professional performance was observed. Key Words: Voice–Voice symptoms–Occupational voice–Quality of life–Telemarketing.
INTRODUCTION Telemarketing is a service of the modern world, and involves significant vocal demands to effectively attain sales goals. Telemarketing companies largely oversee their operators and regularly monitor the quality of service and productivity, and measuring and monitoring a range of information related to individual professional performance.1–3 This oversight has contributed to the intensification of work activity with the aim of increasing productivity. However, these strategies used to improve call center operator performance may favor professional turnover, absenteeism, and the potential for work-related illnesses, which consequently affect professional performance.1–5 To address this issue, Regulatory Norm (RN-17) was enacted by the Brazilian government in 2007 to ensure adequate work conditions for call center operators including furniture and equipment, work organization, environmental conditions, operator training, and occupational health programs. RN-17 emphasizes the importance of wellness and good health as being critical for efficient operator performance.6 Over the last two decades, call center operators have been the subject of many studies on vocal health and quality of life related to voice. The literature suggests a correlation between vocal self-assessment and the perception of the impact of Accepted for publication February 16, 2011. From the *Center for Voice Studies, S~ao Paulo, Brazil; and the ySpeech Language Division Micelli Associates, S~ao Paulo, Brazil. Address correspondence and reprint requests to Tatiana Carvalho Piwowarczyk, Centro de Estudos da Voz, Rua Machado Bittencourt, 361-10 andar, S~ao Paulo - SP 04044-001, Brazil. E-mail: [email protected] Journal of Voice, Vol. 26, No. 2, pp. 194-200 0892-1997/$36.00 Ó 2012 The Voice Foundation doi:10.1016/j.jvoice.2011.02.006
a voice disorder on the quality of life.7–9 However, the correlation between patient perception of voice and clinician assessment of vocal quality is not straightforward, and frequently, a correlation is not observed.10 Perhaps, this lack of correlation is because the patients and clinicians base their analyses on different parameters. The relatively recent increase in investigation in this area is likely because of the high vocal demands associated with this professional practice and the large number of vocal symptoms observed by the operators.11–16 Call center operators report twice as many vocal symptoms as individuals with low vocal demands14 and report increased symptoms during the workday.15 The main vocal symptoms reported are hoarseness, throat clearing, vocal fatigue, dry throat, voice failures, effort to speak, sore throat, and loss of voice.14–16 Attrition is defined as a gradual decline in vocal capacity over time.17 It appears to be related to a disorder and/or alteration of the laryngeal tissue as a result of overuse or inappropriate use of the vocal mechanism that is influenced by behavioral, biological, and psychosomatic characteristics.18 Vocal attrition is clinically associated with vocal fatigue and pain on phonation, among other symptoms,18–20 which in turn can contribute to altered vocal quality.21 This altered voice quality, especially for professionals with significant occupational voice use, may yield reduced productivity and professional performance,14,22,23 participation restriction of daily and social activities,7 limitations of vocal expression and emotional stress, and anxiety regarding the risk of job loss.24,25 Employers of these professionals may observe increased absenteeism and professional turnover and the subsequent costs associated with workforce replacement22 and medical treatment. Although it is largely accepted that a reliable voice contributes to overall
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Symptoms, VAPP, and Performance of Call Center Operators
work performance,23 no studies have confirmed this phenomenon. Aberrant vocal symptoms occur in the general population, but to a smaller degree than those individuals with increased vocal demands.26 However, it is unclear the extent to which call center operators modify their activities, or avoid them completely because of voice complaints, and furthermore, if these complaints influence their professional performance. Therefore, the purpose of this study was to investigate the relationship between the number of vocal symptoms and professional performance of call center operators. Specific dependent variables include job classification, absenteeism, and whether vocal symptoms influence quality of life. Furthermore, we investigated whether individuals who report poor quality of life associated with voice complaints perform at a lower level than the ones that reported good quality of life and did not have voice complaints.
METHODS This study was approved by the Ethics Committee of the Center for Voice (No. 2616/08); all participants provided informed consent. All call center operators who participated in this study were employed by a billing call center of a large retail company. Approximately of the 400 operators in the call center, 247 who had been working for at least 6 months (thus, long enough to have received their first performance evaluation) were contacted about this study. Of these, 157 (139 women and 18 men; Table 1) answered the questionnaire and met the necessary criteria for inclusion. Inclusion criteria included the completion of a performance assessment during the month of data collection and maintaining an active work schedule during that month. Conversely, potential subjects were excluded if they were returning from vacation or sick leave in the month of data collection or those who had not reached the minimum productivity to be classified into quartiles of professional performance despite having worked throughout the month.
TABLE 1. Characteristics of the Study Sample Variables
N
%
Age (yr) Up to 20 21–30 31–40 Over 41
23 91 25 18
14.6 58 15.9 11.5
107 38 12
68.2 24.2 7.6
44 42 24 47
28 26.8 15.3 29.9
Education level Completed secondary school College degree Incomplete higher education Call center experience (yr) At least 1 Between 1 and 2 Between 2 and 3 More than 3
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Two questionnaires were used to investigate the vocal signs and symptoms and the quality of life related to voice. The first was the Vocal Signs and Symptoms Questionnaire (VSSQ).26 The VSSQ contains a list of 14 phonatory and laryngopharyngeal symptoms, which reveals whether the individual has the symptom currently, how often the symptom appears, and whether or not the symptom is caused by work activities as determined by the subject. The second questionnaire was the Voice Activity and Participation Profile (VAPP),7 validated in Brazilian-Portuguese.27,28 This instrument assesses quality of life related to voice and includes 28 questions divided into five categories: severity of voice problem, effect on professional activity, effect on daily communication, effect on social communication, and effect on emotional well-being. Two other additional aspects are scores of activity limitation (SAL) and scores of participation restriction (SPR). After a description of the study and a brief question and answer session, the questionnaires were completed by all the subjects. Data regarding individual professional performance were obtained in the same month as the completion of the voice questionnaires. These data were obtained from the administrative department of the telemarketing center and included number of calls and absences and professional performance in quartiles; the first quartile corresponded to the best performance and the fourth quartile corresponded to the worst performance. A significance level of 0.05 (5%) was considered for all the analyses and all the reliability intervals were based on 95% confidence interval. Nonparametric tests were used for all the analyses because there was neither normality nor homoscedasticity of data. The Friedman test compared the number of current symptoms and the work-related symptoms, and the Wilcoxon test was applied to check statistical differences between them. The Kruskal-Wallis test compares the quartiles of the professional performance with the number of symptoms (Figure 1). The Friedman test is a nonparametric test that compares three or more paired groups, it first ranks the values in each matched set. The Wilcoxon test is a nonparametric test that compares two paired groups. It calculates the difference between each set of pairs, and analyzes that list of differences. The Kruskal-Wallis test is a nonparametric (distribution free) test, which is used to compare three or more groups of sample data, it does not make any assumption on the nature of the underlying distributions (except continuity). The Kruskal-Wallis test also compares the quartiles of the professional performance with VAPP scores. The MannWhitney determined in which variable there were statistical differences (Figure 2). The Mann-Whitney test is a nonparametric test that compares two unpaired groups. The Test for Equality of Two Proportions characterized the presence or absence of current vocal symptoms and work-related vocal symptoms (Table 2). This test also compared the quartiles of professional performance and the number of calls (Figure 3). The Test for Equality of Two Proportions is a nonparametric test that tests the similarity of several population proportions. The KruskalWallis test also compares the quartiles of the professional performance and the mean number of absences per month
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FIGURE 1. Mean of symptoms and work-related symptoms according to quartiles of professional performance. Mean of vocal symptoms 3 workrelated vocal symptoms, P value < 0.001. Symptoms first 3 fourth quartile, P value ¼ 0.571; work-related first 3 fourth quartile, P value ¼ 0.238. Tests: Friedman, Wilcoxon, and Kruskal-Wallis.
(Figure 4). Finally, the Spearman correlation was used for measuring the degree of relationship among the number of symptoms, VAPP score, professional performance, number of calls, and absences (Table 3). Correlations were validated by correlation test.
RESULTS Figure 1 shows the vocal symptoms and work-related vocal symptoms according to quartiles of professional performance. The mean number of vocal symptoms was higher (mean of
6.8 symptoms) and not all subjects who reported symptoms related them to their occupation (mean of 4.29 symptoms). A statistically significant difference was observed between the mean number of symptoms and the mean number of work-related symptoms. However, no significant associations were observed between quartile ranking of professional performance and the mean number of vocal symptoms. Interestingly, relatively low scores were observed on the VAPP (Figure 2). However, a statistically significant association was observed between the higher scores on some aspects of the VAPP and poor business classification, including
FIGURE 2. VAPP scores according to quartiles of professional performance. Severity of voice problem first 3 fourth quartile, P ¼ 0.029; effects on daily communication first 3 fourth quartile, P ¼ 0.016; social communication first 3 fourth quartile, P ¼ 0.003; effect on emotion first 3 fourth quartile, P ¼ 0.014; total VAPP score first 3 fourth quartile, P ¼ 0.018; SPR first 3 fourth quartile, P ¼ 0.005. Tests: Kruskal-Wallis and MannWhitney.
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TABLE 2. Distribution of Current Vocal Symptoms and Work-Related Vocal Symptoms Symptoms No
Work Related Yes
No
Yes
Symptoms
N
%
N
%
P Value
N
%
N
%
P Value
Hoarseness Voice tires or changes quality after using even for a short time Trouble speaking or singing softly Difficulty projecting voice Loss of singing range Discomfort while using voice Monotone voice Effort to talk Dry throat Sore throat Clear throat Acid or bitter taste Swallowing difficulties Wobbly or shaky voice
60 73
38.2 46.5
97 84
61.8 53.5
<0.001 0.214
98 95
62.4 60.5
59 62
37.6 39.5
<0.001 <0.001
98 99 86 88 113 68 38 61 53 98 108 88
62.4 63.1 54.8 56.1 72 43.3 24.2 38.9 33.8 62.4 68.8 56.1
59 58 71 69 44 89 119 96 104 59 49 69
37.6 36.9 45.2 43.9 28 56.7 75.8 61.1 66.2 37.6 31.2 43.9
<0.001 <0.001 0.090 0.032 <0.001 0.018 <0.001 <0.001 <0.001 <0.001 <0.001 0.032
133 124 129 108 137 89 52 92 93 127 140 107
84.7 79 82.2 68.8 87.3 56.7 33.1 58.6 59.2 80.9 89.2 68.2
24 33 28 49 20 68 105 65 64 30 17 50
15.3 21 17.8 31.2 12.7 43.3 66.9 41.4 40.8 19.1 10.8 31.8
<0.001 <0.001 <0.001 <0.001 <0.001 0.018 <0.001 0.002 0.001 <0.001 <0.001 <0.001
Test for Equality of Two Proportions.
self-perception of the severity of voice problem (P ¼ 0.029), effects on daily communication (P ¼ 0.016), social communication (P ¼ 0.003) and on emotion (P ¼ 0.014), and of the total VAPP (P ¼ 0.018) and participation restriction (P ¼ 0.005). Table 2 shows the distribution of all voice and work-related vocal symptoms. A significant increase in the symptoms was observed presently for hoarseness (P < 0.001), effort to talk (P ¼ 0.018), dry throat (P < 0.001), sore throat (P < 0.001), and throat clearing (P < 0.001). The only symptom that significantly related to subject occupation was dry throat (P value < 0.001). Figure 3 shows the number of operators according to the quartile of professional performance and the number of calls performed during the month that the questionnaire was administered. Higher call volume was highly correlated with higher job performance. Figure 4 shows the mean number of absences per professional performance quartile. It can be observed that fewer absences were correlated with better professional classification.
FIGURE 3. Range of number of calls per professional performance quartile. Range between 6001 and 8000: first 3 third quartile, P ¼ 0.001; first 3 fourth quartile, P < 0.001; second 3 fourth quartile, P ¼ 0.019. Test for Equality of Two Proportions.
Table 3 shows significant correlations among vocal symptoms, aspects of VAPP, quartile of job performance, absences, and calls. Increased current vocal symptoms were associated with higher number of calls (16.8%). In addition, lower professional performance quartile (the third and fourth quartiles) correlated with decreased call volume (18%) and higher absenteeism (21.4%) during the month. DISCUSSION The telemarketing industry has experienced many changes over the recent years. The activity of call center operators, which, at first was informal, has evolved into a structured profession with career planning and defined hierarchical levels. Companies are more organized and are modifying the work schedule to unite excellence of service to the quality of life of its operators.29 The present study investigated the relationship between voice symptoms and job performance. Increased insight regarding
FIGURE 4. Mean number of absences per professional performance quartile. Mean number of absences between all quartiles, P value ¼ 0.012; first 3 fourth quartile, P value ¼ 0.006; and third 3 fourth quartile, P value ¼ 0.020. Test: Kruskal-Wallis.
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TABLE 3. Correlation Among Vocal Symptoms, VAPP, Professional Performance Quartile, Absences, and Calls Correlations Current symptoms Work-related symptoms Voice problem severity Effect on work Effect on daily communication Effect on social communication Effect on emotion Total VAPP score SAL SPR Number of calls Professional development quartile Number of calls Number of absences
r (%)
P Value
66.1 36.6 38.7 40.9 32.6 39.4 43.3 44.2 37.8 16.8
<0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 0.036
18 21.4
0.024 0.007
Tests: Spearman correlation and correlation test.
the effects of vocal problems on the performance of the operator is likely to justify investment in activities that promote vocal health and quality of life related to voice in these professionals. The profile of the sample of the present study was similar to other studies, predominantly female and young.14,30 A similar number of operators engaged in the activity for less than a year and for more than 3 years. These data may indicate that the market for telemarketing is still growing, but also that the profession is losing its character as temporary. On the basis of these data, we can see the importance of speechlanguage pathology follow-up in this population as women are more prone to vocal problems14,31,32 especially when exposed to intense voice use over the years.31 The number of vocal symptoms (Figure 1) in our cohort of operators was higher (mean of 6.8 symptoms) than the general population.26 In fact, the number of vocal symptoms in the present study is higher than the same symptoms reported in previous studies with the same questionnaire, by American (mean of 4.3 symptoms)26 and Brazilian (mean of 3.7 symptoms)33 teachers. These data suggest that call center operators are considered high vocal risk employees and deserve special attention regarding working conditions. Figure 1 shows the difference between the means of current symptoms and those related to their work as a call center operator. This information highlights the fact that not everyone who reported current symptoms related these symptoms to their occupation. These findings are contrary to studies of teachers who attributed their vocal symptoms to their profession.26,33 One potential explanation for these findings is that some operators may have obscured the relationship of their symptoms to their work, for fear of professional ramifications. There was no statistically significant relationship between the quartile ranking of professional performance and the mean number of vocal symptoms (Figure 1). These data suggest that professional performance is more likely to be related to the
communicative competence of the operator than to the number of vocal symptoms. However, the threshold between an acceptable number and type of symptoms for effective professional activity should be examined further. Relatively low scores were obtained for the VAPP protocol (Figure 2). These data indicate that, in general, the operators’ current voices are essentially healthy and that participation constraint and limitation of vocal activities are minimal because they presented with similar mean scores to the ones found in the validation of the Brazilian-Portuguese VAPP.27,28 However, a statistically significant relationship was observed between higher scores on some aspects of VAPP and poorer performance classification (Figure 2). This finding is consistent with the literature, which indicates that voice problems can interfere with both productivity and professional performance.14,22,23 Analyzing the components of the VAPP suggests that a slightly increased scores reflective of restriction and limitation of vocal activities may have consequences on the relative quartiles of professional performance. Perhaps, this restriction also affects the communicative competence of call center operators resulting in poorer performance at work. Once again, the VAPP item related to ‘‘effect on work,’’ interestingly, was not significant. As for the distribution of symptoms (Table 2), a significant increase in symptoms of hoarseness, effort to talk, dry throat, sore throat, and clear throat was observed. However, dry throat was significantly attributed to work conditions. This symptom is likely related to the fact that the work environment often includes air conditioning and low humidity.16,34,35 All symptoms reported by the operators in this study have also been described in other studies.14–16,30 The causes of occupational voice problems are varied, likely related to both vocal and environmental factors including background noise, poor acoustics, improper vocal habits, high vocal demands, poor air quality, and health and psychological problems.2,14,36–38 Organizational factors such as work-related stress, reduced number of breaks, unsatisfactory relationships with supervisors and clients, among others may also contribute to the development of vocal problems.16,39 Clearly, efficient vocal performance in telemarketing is not only physiological, but is also highly dependent on a balance between psychological, behavioral, and work environment factors.40 Regarding the number of calls (Figure 3), mainly in the range of 6001–8000 per quartile, we observed that the higher the number of calls, the better the performance classification. In contrast, the higher the number of calls, the higher the number of current vocal symptoms was observed in Table 3. And regarding absences, fewer workdays missed were correlated to improved professional classification (Figure 4). That is, the operator needs to make a higher number of calls (Figure 3) and to work on a larger number of days (Figure 4) to achieve higher work performance. This increased load is likely to potentially jeopardize his or her vocal health and consequently impact the overall work performance. Nevertheless, the best classified operators in the company and those who presented with the highest number of calls and voice symptoms displayed interference and restriction of participation in activities with
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Symptoms, VAPP, and Performance of Call Center Operators
voice use (Figure 2). The correlation analyses (Table 3) also offered other interesting data: the worse the quartile of professional performance (the third and fourth quartiles), the lower the number of calls and the higher is the number of absences during the month. Future studies should, besides verifying and quantifying phonatory and laryngopharyngeal symptoms, analyze the impact of these variables on the quality of life. These data will help provide better assistance to call center operators who will, in turn, develop their professional activity in a more comfortable, healthy, and efficient manner.
CONCLUSION Despite the fact that call center operators presented with increased vocal symptoms compared with the general population, there was no relationship between the mean number of symptoms and professional performance. In addition, operators reported little to no limitation or restriction of participation in activities related to their voice. However, individuals with poor professional performance are typically poorer on some components of the VAPP. In addition, improved professional performance was related to increased call volume and decreased absenteeism. This scenario likely produces increased work-related voice demands that may contribute to the development of vocal problems and may result in decreased professional performance. However, the relationship is not straightforward.
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10. Karnell MP, Melton SD, Childes JM, Coleman TC, Dauley AS, Hoffman HT. Reliability of clinician-based (GRBAS and CAPE-V) and patient-based (V-RQOL and IPVI) documentation of voice disorders. J Voice. 2007;21:576–590. 11. Oliveira AGA, Behlau M, Gouveia N. Vocal symptoms in telemarketers: a random and controlled field trial. Folia Phoniatr Logop. 2009;61: 76–82. 12. Lehto L, Alku P, B€acktr€om T, Vilkman E. Voice symptoms of call-center customer service advisors experienced during a work-day and effects of a short vocal training course. Logoped Phoniatr Vocol. 2005;30:14–27. 13. Lehto L, Rantala L, Vilkman E, Alku P, B€acktr€om T. Experiences of a short vocal training course for call-centre customer service advisors. Folia Phoniatr Logop. 2003;55:163–176. 14. Jones K, Sigmon J, Hock L, Nelson E, Sullivan M, Ogren F. Prevalence and risk factors for voice problems among telemarketers. Arch Otolaryngol Head Neck Surg. 2002;128:571–577. 15. Lehto L, Laaksonen L, Vilkman E, Alku P. Occupational voice complaints and objective acoustic measurements—do they correlate? Logoped Phoniatr Vocol. 2006;31:147–152. 16. Ferreira LP, Akutsu CM, Luciano P, Viviano NAG. Vocal production condition of telemarketing operators: correlation between heath issues and vocal habits and symptoms. Rev Soc Bras Fonoaudiol. 2008;13:307–315. 17. Sapir S, Keidar A, Mathers-Schmidt B. Vocal attrition in teachers: survey findings. Eur J Disord Commun. 1993;28:177–185. 18. Sapir S, Attias J, Shahar A. Symptoms of vocal attrition in women army instructors and new recruits: results from a survey. Laryngoscope. 1990; 100:991–994. 19. Sapir S, Attias J, Shahar A. Vocal attrition related to idiosyncratic dysphonia: re-analysis of survey data. Eur J Disord Commun. 1992;27:129–135. 20. Sapir S. Vocal attrition in voice students: survey findings. J Voice. 1993;7: 69–74. 21. Coyle SM, Weinrich BD, Stemple JC. Shifts in relative prevalence of laryngeal pathology in a treatment-seeking population. J Voice. 2001;15: 424–440. 22. Wingate JM, Brown WS, Shrivastav R, Davenport P, Sapienza CM. Treatment outcomes for professional voice users. J Voice. 2007;21: 433–447. 23. Verdolini K, Ramig LO. Review: occupational risks for voice problems. Logoped Phoniatr Vocol. 2001;26:37–46. 24. Stemple J, Glaze L, Gerdeman B. Clinical Voice Pathology. 2nd ed. San Diego: Singular Publishing; 1995. 25. Hoffman-Ruddy B, Lehaman J, Crandell C, Ingram D, Sapienza C. Laryngostroboscopic, acoustic, and environmental characteristics of high-risk vocal performers. J Voice. 2001;15:543–552. 26. Roy N, Merrill RM, Thibeaults S, Gray SD, Smith EM. Voice disorders in teachers and the general population: effects on work performance, attendance, and future career choices. J Speech Lang Hear Res. 2004;47: 542–551. 27. Ricarte A, Gasparini G, Behlau M. Validation of Voice Activity and Participation Profile (VAPP) in Brazil. Annals of XIV Brazilian SpeechLanguage Pathology and Audiology Congress. Salvador; 2006. 28. Behlau M, Oliveira G, Santos LMA, Ricarte A. Validation in Brazil of selfassessment protocols for dysphonia impact. Pro-Fono R Atual Cient. 2009; 21:326–332. Avaiable at: http://www.scielo.br/pdf/pfono/v21n4/11.pdf. Accessed February 6, 2011. 29. Behlau M, Feijo D, Madazio G, Rehder MI, Azevedo R, Ferreira AE. Professional voice: general aspects and speech therapy practice. In: Behlau M, ed. org. Voice: the book’s specialist, vol 2. S~ao Paulo: Revinter; 2005: 410–564. 30. Charbotel B, Croidieu S, Vohito M, et al. Working conditions in callcenters, the impact on employee health: a transversal study. Part II. Int Arch Occup Environ Health. 2009;82:747–756. 31. Roy N, Merrill RM, Thibeaults S, Parsa R, Gray SD, Smith EM. Prevalence of voice disorders in teachers and the general population. J Speech Lang Hear Res. 2004;47:281–293. 32. Butler J, Hammond T, Gray S. Genser-related differences of hyaluronic acid distribution in the human vocal fold. Laryngoscope. 2001;111: 907–911.
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INTRODUCTION Telemarketing is a service of the modern world, and involves significant vocal demands to effectively attain sales goals. Telemarketing companies largely oversee their operators and regularly monitor the quality of service and productivity, and measuring and monitoring a range of information related to individual professional performance.1–3 This oversight has contributed to the intensification of work activity with the aim of increasing productivity. However, these strategies used to improve call center operator performance may favor professional turnover, absenteeism, and the potential for work-related illnesses, which consequently affect professional performance.1–5 To address this issue, Regulatory Norm (RN-17) was enacted by the Brazilian government in 2007 to ensure adequate work conditions for call center operators including furniture and equipment, work organization, environmental conditions, operator training, and occupational health programs. RN-17 emphasizes the importance of wellness and good health as being critical for efficient operator performance.6 Over the last two decades, call center operators have been the subject of many studies on vocal health and quality of life related to voice. The literature suggests a correlation between vocal self-assessment and the perception of the impact of Accepted for publication February 16, 2011. From the *Center for Voice Studies, S~ao Paulo, Brazil; and the ySpeech Language Division Micelli Associates, S~ao Paulo, Brazil. Address correspondence and reprint requests to Tatiana Carvalho Piwowarczyk, Centro de Estudos da Voz, Rua Machado Bittencourt, 361-10 andar, S~ao Paulo - SP 04044-001, Brazil. E-mail: [email protected] Journal of Voice, Vol. 26, No. 2, pp. 194-200 0892-1997/$36.00 Ó 2012 The Voice Foundation doi:10.1016/j.jvoice.2011.02.006
a voice disorder on the quality of life.7–9 However, the correlation between patient perception of voice and clinician assessment of vocal quality is not straightforward, and frequently, a correlation is not observed.10 Perhaps, this lack of correlation is because the patients and clinicians base their analyses on different parameters. The relatively recent increase in investigation in this area is likely because of the high vocal demands associated with this professional practice and the large number of vocal symptoms observed by the operators.11–16 Call center operators report twice as many vocal symptoms as individuals with low vocal demands14 and report increased symptoms during the workday.15 The main vocal symptoms reported are hoarseness, throat clearing, vocal fatigue, dry throat, voice failures, effort to speak, sore throat, and loss of voice.14–16 Attrition is defined as a gradual decline in vocal capacity over time.17 It appears to be related to a disorder and/or alteration of the laryngeal tissue as a result of overuse or inappropriate use of the vocal mechanism that is influenced by behavioral, biological, and psychosomatic characteristics.18 Vocal attrition is clinically associated with vocal fatigue and pain on phonation, among other symptoms,18–20 which in turn can contribute to altered vocal quality.21 This altered voice quality, especially for professionals with significant occupational voice use, may yield reduced productivity and professional performance,14,22,23 participation restriction of daily and social activities,7 limitations of vocal expression and emotional stress, and anxiety regarding the risk of job loss.24,25 Employers of these professionals may observe increased absenteeism and professional turnover and the subsequent costs associated with workforce replacement22 and medical treatment. Although it is largely accepted that a reliable voice contributes to overall
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work performance,23 no studies have confirmed this phenomenon. Aberrant vocal symptoms occur in the general population, but to a smaller degree than those individuals with increased vocal demands.26 However, it is unclear the extent to which call center operators modify their activities, or avoid them completely because of voice complaints, and furthermore, if these complaints influence their professional performance. Therefore, the purpose of this study was to investigate the relationship between the number of vocal symptoms and professional performance of call center operators. Specific dependent variables include job classification, absenteeism, and whether vocal symptoms influence quality of life. Furthermore, we investigated whether individuals who report poor quality of life associated with voice complaints perform at a lower level than the ones that reported good quality of life and did not have voice complaints.
METHODS This study was approved by the Ethics Committee of the Center for Voice (No. 2616/08); all participants provided informed consent. All call center operators who participated in this study were employed by a billing call center of a large retail company. Approximately of the 400 operators in the call center, 247 who had been working for at least 6 months (thus, long enough to have received their first performance evaluation) were contacted about this study. Of these, 157 (139 women and 18 men; Table 1) answered the questionnaire and met the necessary criteria for inclusion. Inclusion criteria included the completion of a performance assessment during the month of data collection and maintaining an active work schedule during that month. Conversely, potential subjects were excluded if they were returning from vacation or sick leave in the month of data collection or those who had not reached the minimum productivity to be classified into quartiles of professional performance despite having worked throughout the month.
TABLE 1. Characteristics of the Study Sample Variables
N
%
Age (yr) Up to 20 21–30 31–40 Over 41
23 91 25 18
14.6 58 15.9 11.5
107 38 12
68.2 24.2 7.6
44 42 24 47
28 26.8 15.3 29.9
Education level Completed secondary school College degree Incomplete higher education Call center experience (yr) At least 1 Between 1 and 2 Between 2 and 3 More than 3
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Two questionnaires were used to investigate the vocal signs and symptoms and the quality of life related to voice. The first was the Vocal Signs and Symptoms Questionnaire (VSSQ).26 The VSSQ contains a list of 14 phonatory and laryngopharyngeal symptoms, which reveals whether the individual has the symptom currently, how often the symptom appears, and whether or not the symptom is caused by work activities as determined by the subject. The second questionnaire was the Voice Activity and Participation Profile (VAPP),7 validated in Brazilian-Portuguese.27,28 This instrument assesses quality of life related to voice and includes 28 questions divided into five categories: severity of voice problem, effect on professional activity, effect on daily communication, effect on social communication, and effect on emotional well-being. Two other additional aspects are scores of activity limitation (SAL) and scores of participation restriction (SPR). After a description of the study and a brief question and answer session, the questionnaires were completed by all the subjects. Data regarding individual professional performance were obtained in the same month as the completion of the voice questionnaires. These data were obtained from the administrative department of the telemarketing center and included number of calls and absences and professional performance in quartiles; the first quartile corresponded to the best performance and the fourth quartile corresponded to the worst performance. A significance level of 0.05 (5%) was considered for all the analyses and all the reliability intervals were based on 95% confidence interval. Nonparametric tests were used for all the analyses because there was neither normality nor homoscedasticity of data. The Friedman test compared the number of current symptoms and the work-related symptoms, and the Wilcoxon test was applied to check statistical differences between them. The Kruskal-Wallis test compares the quartiles of the professional performance with the number of symptoms (Figure 1). The Friedman test is a nonparametric test that compares three or more paired groups, it first ranks the values in each matched set. The Wilcoxon test is a nonparametric test that compares two paired groups. It calculates the difference between each set of pairs, and analyzes that list of differences. The Kruskal-Wallis test is a nonparametric (distribution free) test, which is used to compare three or more groups of sample data, it does not make any assumption on the nature of the underlying distributions (except continuity). The Kruskal-Wallis test also compares the quartiles of the professional performance with VAPP scores. The MannWhitney determined in which variable there were statistical differences (Figure 2). The Mann-Whitney test is a nonparametric test that compares two unpaired groups. The Test for Equality of Two Proportions characterized the presence or absence of current vocal symptoms and work-related vocal symptoms (Table 2). This test also compared the quartiles of professional performance and the number of calls (Figure 3). The Test for Equality of Two Proportions is a nonparametric test that tests the similarity of several population proportions. The KruskalWallis test also compares the quartiles of the professional performance and the mean number of absences per month
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FIGURE 1. Mean of symptoms and work-related symptoms according to quartiles of professional performance. Mean of vocal symptoms 3 workrelated vocal symptoms, P value < 0.001. Symptoms first 3 fourth quartile, P value ¼ 0.571; work-related first 3 fourth quartile, P value ¼ 0.238. Tests: Friedman, Wilcoxon, and Kruskal-Wallis.
(Figure 4). Finally, the Spearman correlation was used for measuring the degree of relationship among the number of symptoms, VAPP score, professional performance, number of calls, and absences (Table 3). Correlations were validated by correlation test.
RESULTS Figure 1 shows the vocal symptoms and work-related vocal symptoms according to quartiles of professional performance. The mean number of vocal symptoms was higher (mean of
6.8 symptoms) and not all subjects who reported symptoms related them to their occupation (mean of 4.29 symptoms). A statistically significant difference was observed between the mean number of symptoms and the mean number of work-related symptoms. However, no significant associations were observed between quartile ranking of professional performance and the mean number of vocal symptoms. Interestingly, relatively low scores were observed on the VAPP (Figure 2). However, a statistically significant association was observed between the higher scores on some aspects of the VAPP and poor business classification, including
FIGURE 2. VAPP scores according to quartiles of professional performance. Severity of voice problem first 3 fourth quartile, P ¼ 0.029; effects on daily communication first 3 fourth quartile, P ¼ 0.016; social communication first 3 fourth quartile, P ¼ 0.003; effect on emotion first 3 fourth quartile, P ¼ 0.014; total VAPP score first 3 fourth quartile, P ¼ 0.018; SPR first 3 fourth quartile, P ¼ 0.005. Tests: Kruskal-Wallis and MannWhitney.
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TABLE 2. Distribution of Current Vocal Symptoms and Work-Related Vocal Symptoms Symptoms No
Work Related Yes
No
Yes
Symptoms
N
%
N
%
P Value
N
%
N
%
P Value
Hoarseness Voice tires or changes quality after using even for a short time Trouble speaking or singing softly Difficulty projecting voice Loss of singing range Discomfort while using voice Monotone voice Effort to talk Dry throat Sore throat Clear throat Acid or bitter taste Swallowing difficulties Wobbly or shaky voice
60 73
38.2 46.5
97 84
61.8 53.5
<0.001 0.214
98 95
62.4 60.5
59 62
37.6 39.5
<0.001 <0.001
98 99 86 88 113 68 38 61 53 98 108 88
62.4 63.1 54.8 56.1 72 43.3 24.2 38.9 33.8 62.4 68.8 56.1
59 58 71 69 44 89 119 96 104 59 49 69
37.6 36.9 45.2 43.9 28 56.7 75.8 61.1 66.2 37.6 31.2 43.9
<0.001 <0.001 0.090 0.032 <0.001 0.018 <0.001 <0.001 <0.001 <0.001 <0.001 0.032
133 124 129 108 137 89 52 92 93 127 140 107
84.7 79 82.2 68.8 87.3 56.7 33.1 58.6 59.2 80.9 89.2 68.2
24 33 28 49 20 68 105 65 64 30 17 50
15.3 21 17.8 31.2 12.7 43.3 66.9 41.4 40.8 19.1 10.8 31.8
<0.001 <0.001 <0.001 <0.001 <0.001 0.018 <0.001 0.002 0.001 <0.001 <0.001 <0.001
Test for Equality of Two Proportions.
self-perception of the severity of voice problem (P ¼ 0.029), effects on daily communication (P ¼ 0.016), social communication (P ¼ 0.003) and on emotion (P ¼ 0.014), and of the total VAPP (P ¼ 0.018) and participation restriction (P ¼ 0.005). Table 2 shows the distribution of all voice and work-related vocal symptoms. A significant increase in the symptoms was observed presently for hoarseness (P < 0.001), effort to talk (P ¼ 0.018), dry throat (P < 0.001), sore throat (P < 0.001), and throat clearing (P < 0.001). The only symptom that significantly related to subject occupation was dry throat (P value < 0.001). Figure 3 shows the number of operators according to the quartile of professional performance and the number of calls performed during the month that the questionnaire was administered. Higher call volume was highly correlated with higher job performance. Figure 4 shows the mean number of absences per professional performance quartile. It can be observed that fewer absences were correlated with better professional classification.
FIGURE 3. Range of number of calls per professional performance quartile. Range between 6001 and 8000: first 3 third quartile, P ¼ 0.001; first 3 fourth quartile, P < 0.001; second 3 fourth quartile, P ¼ 0.019. Test for Equality of Two Proportions.
Table 3 shows significant correlations among vocal symptoms, aspects of VAPP, quartile of job performance, absences, and calls. Increased current vocal symptoms were associated with higher number of calls (16.8%). In addition, lower professional performance quartile (the third and fourth quartiles) correlated with decreased call volume (18%) and higher absenteeism (21.4%) during the month. DISCUSSION The telemarketing industry has experienced many changes over the recent years. The activity of call center operators, which, at first was informal, has evolved into a structured profession with career planning and defined hierarchical levels. Companies are more organized and are modifying the work schedule to unite excellence of service to the quality of life of its operators.29 The present study investigated the relationship between voice symptoms and job performance. Increased insight regarding
FIGURE 4. Mean number of absences per professional performance quartile. Mean number of absences between all quartiles, P value ¼ 0.012; first 3 fourth quartile, P value ¼ 0.006; and third 3 fourth quartile, P value ¼ 0.020. Test: Kruskal-Wallis.
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TABLE 3. Correlation Among Vocal Symptoms, VAPP, Professional Performance Quartile, Absences, and Calls Correlations Current symptoms Work-related symptoms Voice problem severity Effect on work Effect on daily communication Effect on social communication Effect on emotion Total VAPP score SAL SPR Number of calls Professional development quartile Number of calls Number of absences
r (%)
P Value
66.1 36.6 38.7 40.9 32.6 39.4 43.3 44.2 37.8 16.8
<0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 <0.001 0.036
18 21.4
0.024 0.007
Tests: Spearman correlation and correlation test.
the effects of vocal problems on the performance of the operator is likely to justify investment in activities that promote vocal health and quality of life related to voice in these professionals. The profile of the sample of the present study was similar to other studies, predominantly female and young.14,30 A similar number of operators engaged in the activity for less than a year and for more than 3 years. These data may indicate that the market for telemarketing is still growing, but also that the profession is losing its character as temporary. On the basis of these data, we can see the importance of speechlanguage pathology follow-up in this population as women are more prone to vocal problems14,31,32 especially when exposed to intense voice use over the years.31 The number of vocal symptoms (Figure 1) in our cohort of operators was higher (mean of 6.8 symptoms) than the general population.26 In fact, the number of vocal symptoms in the present study is higher than the same symptoms reported in previous studies with the same questionnaire, by American (mean of 4.3 symptoms)26 and Brazilian (mean of 3.7 symptoms)33 teachers. These data suggest that call center operators are considered high vocal risk employees and deserve special attention regarding working conditions. Figure 1 shows the difference between the means of current symptoms and those related to their work as a call center operator. This information highlights the fact that not everyone who reported current symptoms related these symptoms to their occupation. These findings are contrary to studies of teachers who attributed their vocal symptoms to their profession.26,33 One potential explanation for these findings is that some operators may have obscured the relationship of their symptoms to their work, for fear of professional ramifications. There was no statistically significant relationship between the quartile ranking of professional performance and the mean number of vocal symptoms (Figure 1). These data suggest that professional performance is more likely to be related to the
communicative competence of the operator than to the number of vocal symptoms. However, the threshold between an acceptable number and type of symptoms for effective professional activity should be examined further. Relatively low scores were obtained for the VAPP protocol (Figure 2). These data indicate that, in general, the operators’ current voices are essentially healthy and that participation constraint and limitation of vocal activities are minimal because they presented with similar mean scores to the ones found in the validation of the Brazilian-Portuguese VAPP.27,28 However, a statistically significant relationship was observed between higher scores on some aspects of VAPP and poorer performance classification (Figure 2). This finding is consistent with the literature, which indicates that voice problems can interfere with both productivity and professional performance.14,22,23 Analyzing the components of the VAPP suggests that a slightly increased scores reflective of restriction and limitation of vocal activities may have consequences on the relative quartiles of professional performance. Perhaps, this restriction also affects the communicative competence of call center operators resulting in poorer performance at work. Once again, the VAPP item related to ‘‘effect on work,’’ interestingly, was not significant. As for the distribution of symptoms (Table 2), a significant increase in symptoms of hoarseness, effort to talk, dry throat, sore throat, and clear throat was observed. However, dry throat was significantly attributed to work conditions. This symptom is likely related to the fact that the work environment often includes air conditioning and low humidity.16,34,35 All symptoms reported by the operators in this study have also been described in other studies.14–16,30 The causes of occupational voice problems are varied, likely related to both vocal and environmental factors including background noise, poor acoustics, improper vocal habits, high vocal demands, poor air quality, and health and psychological problems.2,14,36–38 Organizational factors such as work-related stress, reduced number of breaks, unsatisfactory relationships with supervisors and clients, among others may also contribute to the development of vocal problems.16,39 Clearly, efficient vocal performance in telemarketing is not only physiological, but is also highly dependent on a balance between psychological, behavioral, and work environment factors.40 Regarding the number of calls (Figure 3), mainly in the range of 6001–8000 per quartile, we observed that the higher the number of calls, the better the performance classification. In contrast, the higher the number of calls, the higher the number of current vocal symptoms was observed in Table 3. And regarding absences, fewer workdays missed were correlated to improved professional classification (Figure 4). That is, the operator needs to make a higher number of calls (Figure 3) and to work on a larger number of days (Figure 4) to achieve higher work performance. This increased load is likely to potentially jeopardize his or her vocal health and consequently impact the overall work performance. Nevertheless, the best classified operators in the company and those who presented with the highest number of calls and voice symptoms displayed interference and restriction of participation in activities with
Tatiana Carvalho Piwowarczyk, et al
Symptoms, VAPP, and Performance of Call Center Operators
voice use (Figure 2). The correlation analyses (Table 3) also offered other interesting data: the worse the quartile of professional performance (the third and fourth quartiles), the lower the number of calls and the higher is the number of absences during the month. Future studies should, besides verifying and quantifying phonatory and laryngopharyngeal symptoms, analyze the impact of these variables on the quality of life. These data will help provide better assistance to call center operators who will, in turn, develop their professional activity in a more comfortable, healthy, and efficient manner.
CONCLUSION Despite the fact that call center operators presented with increased vocal symptoms compared with the general population, there was no relationship between the mean number of symptoms and professional performance. In addition, operators reported little to no limitation or restriction of participation in activities related to their voice. However, individuals with poor professional performance are typically poorer on some components of the VAPP. In addition, improved professional performance was related to increased call volume and decreased absenteeism. This scenario likely produces increased work-related voice demands that may contribute to the development of vocal problems and may result in decreased professional performance. However, the relationship is not straightforward.
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