Perceived job stress and health complaints at a bank call center: comparison between inbound and outbound services.

Abstract

This study investigated how perceived job stress and health status differ, as well as the relationships to inbound (incoming calls) versus outbound (outgoing calls) calling activities, for call center workers in a bank in Taiwan. The sample bank employed 289 call center workers at the time of the survey, ranging in age from 19 to 54 yr old. Data were obtained on individual factors, health complaints, perceived level job stress, and major job stressors. Overall, 33.5% of outbound operators and 27.1% of inbound operators reported frequently or always experiencing high stress at work, however, the differences between inbound and outbound operators were insignificant. "Having to deal with difficult customers" was the most frequent job stressor for all workers. Musculoskeletal discomfort, eye strain, and hoarse or sore throat were the most prevalent complaints among call center workers. The relationship between perceived job stress and health complaints indicated that workers who perceived higher job stress had significantly increased risk of multiple health problems, including eye strain, tinnitus, hoarse or sore throat, chronic cough with phlegm, chest tightness, irritable stomach or peptic ulcers, and musculoskeletal discomfort (with odds ratios ranging from 2.13 to 8.24). These analytical results suggest that perceived job stress in the call center profoundly affected worker health. This study identified main types of job stressors requiring further investigation.

Full text

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Introduction
Call centers are a rapidly growing industry in many
countries. The call center industry experiences an annu-
al growth of 30–35% in terms of call volumes and
20–25% in numbers of agents1). Rocha et al.2)reported
a 30% increase in the number of call centers in Brazil
during the last 20 yr. Moreover, an estimated 1–2% of
the European work-force is employed in call centers, and
this proportion is expected to grow3). Call center opera-
tors spend most of their time transacting business via
phones fitted with earpieces, usually supported by com-
puters, and possibly using catalogue holders for ease of
access of reference materials, calculators, and other acces-
sories4). Call center services generally comprise one of
the following two types. The first type deals with incom-
ing customer calls (inbound services), with the workers
providing customer services. The second type conducts
simple sales activities or market surveys (outbound ser-
vices) on prospecting for new clients. Ferreira and
Saldiva5)indicated that computer-telephone interactive
Industrial Health 2010, 48, 349–356
Original Article
Perceived Job Stress and Health Complaints
at a Bank Call Center: Comparison between
Inbound and Outbound Services
Yen-Hui LIN1, 2*, Chih-Yong CHEN3, Wei-Hsien HONG4and Yu-Chao LIN5
1School of Occupational Safety and Health, Chung Shan Medical University, No. 110, Sec.1 Jianguo North
Rd., Taichung 402, Taiwan, R.O.C.
2Department of Occupational Medicine, Chung Shan Medical University Hospital, Taiwan, R.O.C.
3Institute of Occupational Safety and Health, Council of Labor Affairs, Taiwan, R.O.C.
4Department of Sports Medicine, China Medical University, Taiwan, R.O.C.
5Department of Business Management, National United University, Taiwan, R.O.C.
Received February 19, 2009 and accepted October 27, 2009
Abstract: This study investigated how perceived job stress and health status differ, as well as
the relationships to inbound (incoming calls) versus outbound (outgoing calls) calling activities,
for call center workers in a bank in Taiwan. The sample bank employed 289 call center work-
ers at the time of the survey, ranging in age from 19 to 54 yr old. Data were obtained on indi-
vidual factors, health complaints, perceived level job stress, and major job stressors. Overall,
33.5% of outbound operators and 27.1% of inbound operators reported frequently or always
experiencing high stress at work, however, the differences between inbound and outbound oper-
ators were insignificant. “Having to deal with difficult customers” was the most frequent job
stressor for all workers. Musculoskeletal discomfort, eye strain, and hoarse or sore throat were
the most prevalent complaints among call center workers. The relationship between perceived
job stress and health complaints indicated that workers who perceived higher job stress had sig-
nificantly increased risk of multiple health problems, including eye strain, tinnitus, hoarse or sore
throat, chronic cough with phlegm, chest tightness, irritable stomach or peptic ulcers, and mus-
culoskeletal discomfort (with odds ratios ranging from 2.13 to 8.24). These analytical results sug-
gest that perceived job stress in the call center profoundly affected worker health. This study
identified main types of job stressors requiring further investigation.
Key words:
Questionnaire
Health complaints, Call center, Perceived job stress, Incoming call, Outgoing call,
*To whom correspondence should be addressed.
E-mail: yann@csmu.edu.tw

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tasks, as performed for inbound or outbound services, are
unique and thus require special study. Ferreira and
Saldiva indicated that call centers working on outbound
services faced higher productivity pressures and conflicts
associated with supervisors than did those working on
inbound services, but that work related to inbound ser-
vices was more repetitive, and lacked autonomy and a
structured work/rest schedule. Previous studies have
demonstrated clear differences between the work loads of
workers providing inbound and outbound services.
However, no previous study has identified specific stres-
sors for the two types of call center tasks.
Numerous studies have examined productivity, work-
related stress, musculoskeletal disorders and caller quali-
ty service issues in call-center workers6–14). For instance,
Burton et al.12)indicated that productivity decreases as
the health risks faced by call center operators increase.
Furthermore, DiTecco et al.6)developed a questionnaire
which contains measures of perceived stress, potential job
stressors, management practices in feedback and moni-
toring, and worker monitoring preferences. Their ques-
tionnaire was distributed among 411 long-distance tele-
phone operators and 396 directory-assistance telephone
operators working in a large Canadian telecommunica-
tions company. They identified call-time pressures i.e.,
having to process a customer call within a specific num-
ber of seconds has having the strongest relationship to job
stress as perceived by workers, and furthermore over 50%
of workers reported that call monitoring contributed to
stress.
However, few studies have examined the multiple
health risks that call center workers face in relation to job
stress in the workplace, particularly in banks, which are
currently facing intense market competition. This study
thus employed a cross-sectional questionnaire survey
dealing with individual factors, health status, perceived
job stress levels, and main job stressors to examine rates
of subjective physical discomfort, prevalence of job stress
and patterns of major job stressors among two main
groups of call center workers at a bank, i.e. those deal-
ing with inbound and outbound services. Additionally,
this study examined the associations between job stress
and self-perceived health status, as well as, and how they
differed between inbound and outbound services.
Subjects and Methods
Subjects and job description
The call center in this study was established in 2001
by a commercial bank to provide telecommunication and
information-related services, for example handling ques-
tions related to commercial bank products and services,
including information on product promotions, customer
account status and service fees. The center employs 308
operators (188 inbound operators and 120 outbound oper-
ators, aged 19 to 54 yr old, with a mean of 33.6 yr), super-
vised by one director and two assistant supervisors. For
inbound services, the pace of work is machine-controlled
i.e., calls are computer-routed to available operators, and
operators handle approximately 120 to 150 calls each 8 h
day. Outbound operators comprise the first link between
customers and the commercial bank regarding business
matters. Outbound operators are primarily responsible for
sales (explaining bank services and costs to customers),
and handle approximately 120 calls daily. All staff
required a high school diploma and proficient communi-
cation skills, including the ability to express themselves
clearly. Among them, only general employees belonging
to the two major concerned groups of inbound and out-
bound services were considered for further study.
Overall, 308 call center operators agreed to participate.
Nineteen operators were excluded for being at their cur-
rent job less than six months, leaving a final sample of
289 operators. Inbound operators provided 171 usable
returns, while outbound operators provided 118 usable
returns, representing response rates of 91% and 98%,
respectively, for the two groups.
Questionnaire design
The self-administered questionnaires were accompanied
by a letter encouraging participation, signed by both the
managers and supervisors of the call centers and deliv-
ered to each subject by a trained interviewer in May 2006.
All subjects were informed of the study objectives prior
to participation, and participated voluntarily. Subjects
completed the questionnaires during their leisure time,
with the process taking between 15 and 20 min. To pro-
tect the confidentiality of individual worker data against
managerial or employer access, subjects completed the
questionnaires anonymously and returned them directly to
the interviewers. On completing the questionnaire, the
interviewer performed an on-site check for completeness.
The questionnaire obtained data on the following main
areas: (1) Individual factors: age, sex, marital status,
length of employment in current company, full/part time
work, and weekly hours spent on physical exercise.
(2) Health status: participants were asked if over the past
12 months they had experienced the following symptoms
at least weekly, and were further asked to rank the sever-
ity on a scale ranging from moderate to severe (yes/no):
“itchy skin”, “eye strain”, “tinnitus”, “hoarse or sore
throat”, “chronic coughing with phlegm”, “chest tight-
ness”, “irritable stomach or peptic ulcers”, and “muscu-
loskeletal discomfort”. (3) Perceived job stress and major
job stressors. Psychological stress and potential job stres-
sors were gathered via a series of questions translated
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Industrial Health 2010, 48, 349–356

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from DiTecco et al6). Perceived stress was measured
using self-reported responses to the question “How fre-
quently do you feel very stressed at work?”, with respons-
es being recorded on a five-point scale, comprising
1=never, 2=seldom, 3=sometimes, 4=frequently, and
5=always. Regarding job stressors, participants were
asked to rank the main stressors contributing to their work
stress referring to a list of possible job stressors. Ten job
stressors believed to capture the main sources of job stress
among workers were described, including: (1) being mon-
itored by a manager without being informed; (2) having
to deal with difficult customers; (3) system monitoring of
operator call activities; (4) calls that take a long time to
process; (5) difficulties in talking to co-workers while sit-
ting at their workstations; (6) difficulty in providing good
customer service while simultaneously meeting time tar-
gets; (7) devices for controlling call time; (8) insufficient
rest breaks; (9) being expected to remain constantly at
ones workstation; and (10) being distracted by other work-
ers.
Psychosocial job characteristics were assessed using a
22-item Job Content Questionnaire (C-JCQ), revised from
the Job Content Questionnaire (JCQ) of Karasek et al.
and translated into Chinese15). These analyses employed
the job control dimension by summing two subscales: skill
discretion, comprising six measurement items, and deci-
sion authority, comprising three measurement items. The
job demand scale comprised five items. The work-relat-
ed social support scale was the sum of two subscales,
namely support from supervisors and support from co-
workers, each measured using four items. The response
to each item was recorded using a four-point Likert scale,
ranging from 1 (strongly disagree) to 4 (strongly agree).
The C-JCQ was designed for domestic workers in Taiwan
and was tested and validated16). Briefly, psychosocial job
constraint was measured with a twenty-two-item scale
with internal consistency reliability (Cronbach’s alpha) of
0.85.
Data analysis
A comparison was made of demographic characteris-
tics between inbound and outbound workers, including
such characteristics as age, sex, length of employment in
their current company, weekly time spent on physical
exercise, marital status, full time versus part time work,
and frequency of health problems based on the Student’s
t-test or Pearson χ2test. Multivariate logistic regression
models were used to assess the associations between per-
ceived levels of job stress and various health complaints.
The odds ratio (OR) and its 95% confidence interval (CI)
were calculated for each independent variable. All sta-
tistical analyses were performed using SPSS release 11.5
for Windows, with a significance level of 5%.
Results
Prevalence of individual and health complaints
Table 1 lists the self-reported demographic data for
both groups. Inbound and outbound services displayed
no significant difference for age, sex, length of employ-
ment, weekly time spent on physical exercise, marital sta-
tus, and full-time versus part-time work (Table 1). Table
1 also lists reports of health complaints occurring in the
current job differences between the inbound and outbound
services. For inbound services, “musculoskeletal dis-
comfort” (88%) was the most prevalent health complaint,
followed by “hoarse or sore throat” (85%), “eye strain”
(84%), “tinnitus” (59%), “chronic cough with phlegm”
(50%), “irritable stomach or peptic ulcers” (42%), “chest
tightness” (35%), and “itchy skin” (29%). Meanwhile,
“musculoskeletal discomfort” (85%) was found to be the
most frequent health complaint across all body areas in
outbound services, but the rankings of other health com-
plaints differed between inbound and outbound services.
Furthermore, for all body areas, inbound services dis-
played higher prevalence of “itchy skin” (29% vs. 22%),
“eye strain” (84% vs. 79%), “tinnitus” (59% vs. 32%),
“hoarse or sore throat” (85% vs. 70%), and “muscu-
loskeletal discomfort” (88% vs. 85%) than did outbound
services. Significant differences existed for “tinnitus”
(p<0.01), “hoarse or sore throat” (p<0.01), and “irritable
stomach or peptic ulcers” (p<0.05) between inbound and
outbound services (Table 1).
Perceived job stress and major job stressors
To compare the association between perceived job
stress and the two call center tasks, the authors choose to
describe level of job stress at work frequently or always
as a high-stress. The observed results revealed that out-
bound services (33.5%) displayed a higher prevalence of
high-stress than inbound services (27.1%), but the differ-
ence was insignificant (p=0.247). This study also exam-
ined patterns of major job stressors. For inbound ser-
vices, the most significant source of job stress was ‘hav-
ing to deal with difficult customers’, identified by 54.0%
of subjects. ‘Devices for controlling call time’ (46.3%)
were the second-most-frequent source of job stress, fol-
lowed by ‘being monitored by a manager without being
informed’ (44.1%), ‘system monitoring of operator call
activities’ (36.8%), ‘calls that take a long time to process’
(32.9%), ‘difficulty in providing good customer service
while simultaneously meeting time targets’ (31.3%),
‘insufficient rest breaks’ (23.9%), ‘being expected to
remain constantly at ones workstation’ (23.1%), ‘diffi-
culty in talking to co-workers while sitting at their work-
stations’ (12.9%), and ‘being distracted by other workers’
(0.9%). On the other hand, ‘having to deal with difficult
INBOUND AND OUTBOUND CALLING SERVICES
351

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customers’ (54.4%) was also found to be the most fre-
quent job stressor for outbound services, while the ranks
of the other major OR main job stressors differed between
inbound and outbound services (Table 2).
Ratings for psychosocial factors differed significantly
between the inbound and outbound operators (Table 3).
Outbound operators significantly outscored inbound oper-
ators in skill discretion, decision authority, job control,
supervision support, and work-related support. In con-
trast, inbound operators scored slightly higher in job
demands. Thus, outbound operators reported high job
control and low work demands in this study. Ratings on
C-JCQ for the psychosocial factors of outbound workers
were compared with those obtained from the survey of
Taiwanese workers conducted by Cheng et al16). Table
3 clearly shows that outbound operators scored slightly
lower than male operators in skill discretion, decision
authority, job control, and job demands. However, out-
bound operators scored slightly higher than male telecom-
munication company call center operators in skill discre-
tion, decision authority, job control. Conversely, out-
bound operators displayed low job demands and high
352
Y-H LIN et al.
Industrial Health 2010, 48, 349–356
Table 1. Comparison of mean and percentage distribution of demographic characteristics and
health complaints for inbound and outbound services
Table 2. Rankings of major job stressors and reporting percentages of study subjects for inbound
operators (n=171) and outbound operators (n=118)

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work-related support8).
Association between perceived levels of job stress and
health complaints
Table 4 summarizes the results of the multivariate
logistic regression analyses. Subjects who reported
“always” or “frequently” feeling very stressed at work
were classified as the High-Stress group, those who
reported only “sometimes” feeling very stressed were
classed as the Intermediate-Stress group, and those who
reported “never” or “seldom” feeling very stressed were
assigned to the Low-Stress group. Since the prevalence
of high stress did not differ significantly between inbound
and outbound services (p=0.247), these two service
groups were combined for the purposes of this investiga-
tion. Compared with the Low-Stress group, The High-
Stress group had significantly increased risks of various
health problems. Table 3 showed that higher levels of
job stress were associated with “eye strain” (odds ratio
[OR]=2.50, 95%CI=1.07–5.87), “tinnitus” (OR=4.53,
95%CI=2.05–9.98), “hoarse or sore throat” (OR=2.96,
95%CI=1.16–7.54), “chronic cough with phlegm”
(OR=2.13, 95%CI=1.02–4.44), “chest tightness” (OR=3.85,
95%CI=1.73–8.57), “irritable stomach or peptic ulcers”
(OR=8.24, 95%CI=3.56–19.09) and “musculoskeletal dis-
comfort” (OR=6.46, 95%CI=2.27–18.33).
Discussion
Health complaints and job stress survey
Call center workers displayed a significantly raised
prevalence of “musculoskeletal discomfort” (inbound:
88% vs. outbound: 85%), as listed in Table 1. The preva-
lence of “musculoskeletal discomfort” was compared with
data obtained by the Institute of Occupational Safety and
Health of Taiwan17)for all industries, as part of its peri-
odic survey of physical discomfort. The analytical results
indicated that the prevalence of “musculoskeletal dis-
comfort” for workers in this call center significantly
exceeded the industry average (63.3% for “muscu-
loskeletal discomfort”). Self-reported “musculoskeletal
discomfort” is associated with activities such as heavy
physical work, and with psychosocial and environmental
stress. In call center work, the main influences besides
non-dynamic sitting are psychosocial factors5). In this
investigation, 33.5% of outbound service call center work-
ers and 27.1% of inbound service call center workers were
classified as suffering high stress, considerably higher
than figures from a wider survey of the working popula-
tion in Taiwan, which identified high stress in just 7.6%
INBOUND AND OUTBOUND CALLING SERVICES
353
Table 3. Distributions of the C-JCQ scores of the study sample vs. those of Taiwanese workers in general

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of male workers and 6.5% of female workers18).
Furthermore, this study observed that inbound services
may be associated with higher prevalence of “muscu-
loskeletal discomfort” than
Differences in task loads should be compared between
inbound and outbound services. Unfortunately, this study
did not use self-reporting or observation to identify dif-
ferences, for example differences related to mental, emo-
tional, psychosocial, and environmental loads.
Nearly one-third of the workers (inbound: 27.1% vs.
outbound: 33.5%) were classified as belonging to the high
stress group, significantly lower than in the study of
DiTecco et al.6)(57%). One explanation for this phe-
nomenon was that inbound service call-center workers
handled between 120 and 150 calls daily, each averaging
120–150 s, representing a reasonably manageable work-
load. Supervisors paid attention to workers who under-
performed the office average but did not penalize them.
Furthermore, the finding that outbound services were
outbound services.
associated with higher job stress than inbound services
was consistent with the finding of Ferreira and Saldiva5)
that outbound services faced greater productivity pressure
and supervisor-related conflicts than did inbound services.
The association between high levels of job stress and
health complaints in this study suggests that call center
work is characterized by job stress, in turn possibly result-
ing in high levels of health problems. Several studies
have identified job stress as an important risk factor for
health-related quality of life19, 20). Consistent with previ-
ous studies, dose-response associations were observed
between levels of job stress and increased risks of multi-
ple self-reported health complaints in bank call center
workers.
Comparison of job stressors
This study identified differences in sources of job stres-
sors between call center workers providing inbound and
outbound services (Table 2). Notably, most of the study
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Industrial Health 2010, 48, 349–356
Table 4. Multivariable odds ratio (OR) with 95% confidence intervals (CI) for
health complaints and stress levels among call center operators

Page 7

subjects, namely 54.0% for inbound services and 54.4%
for outbound services, considered “having to deal with
difficult customers” to be the top job stressor. This find-
ing differed from that of DiTecco et al.6), namely that the
main job stressor was “difficulty in providing good cus-
tomer service while simultaneously meeting time targets”.
This study and that of DiTecco et al.6)examined all the
main job stressors, and operators of both studies report-
ed similar specific stressors contributing to their feelings
of job stress, for example “difficulty in providing good
customer service while simultaneously meeting time tar-
gets”, “system monitoring of operator call activities”, and
“being monitored by a manager without being informed”.
However, this investigation asked workers to rank the
main stressors, which was a forced choice task. Possibly,
subjects would have preferred to indicate no, or just one
or two major stressors; in which case the forced choice
task would lead to unrealistically high percentages and
overestimations of the
Additionally, information on minor stressors, with poten-
tial to differentiate between groups, is lost in this situa-
tion.
importance of stressors.
Study limitations and future research
Various improvements could refine the current investi-
gation. For example, the investigation focuses on a sin-
gle banking call center, it would be interesting to analyze
call centers of firms engaged in different businesses.
Additionally, both self-recording and observation meth-
ods could be used to identify differences, such as those
involving mental, emotional, psychosocial, and environ-
mental load. Possible (semi-) quantitative parameters
could also be obtained, including call number and dura-
tion, number of conflicting calls, number of calls catego-
rized according to difficulty, and computer workstation
parameters. A further limitation of this study is that the
sample size of subjects (171 inbound and 118 outbound
operators) could be considered too small to clearly iden-
tify relationships between stress and health complaints,
preventing the generalization of the results to all studies
involving call center tasks, however, they represent almost
all workers in current activity in those departments, thus
helping avoid selection bias5). Another limitation of this
investigation is that health complaints were self-reported
and based on symptoms rather than on detailed medical
examinations. Meanwhile, the study adopted a transver-
sal design, and data on stress and medical conditions were
collected simultaneously. Thus it is impossible to con-
clude to a causal relationship between stress and medical
conditions subjects with bad medical conditions are pos-
sible to describe a high level of perceived stress.
Conclusion
This study identified “musculoskeletal discomfort”,
“eye strain”, and “hoarse or sore throat” as the most
prevalent health complaints at a bank call center.
Additionally, call center workers providing outbound ser-
vices were more likely than those providing inbound ser-
vices to report frequently or always feeling very stressed
at work. Furthermore, “having to deal with difficult cus-
tomers” was the most frequent job stressor facing opera-
tors. Finally, the association between perceived job stress
and health complaints indicated that workers who per-
ceived high job stress had significantly increased risks of
multiple health problems.
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