December 2007 Perspectives 5 Statistics Canada — Catalogue no. 75-001-XIE
Jungwee Park is with the Labour and Household Surveys
Analysis Division. He can be reached at 613-951-4598 or perspectives@statcan.ca. Work stress and job performance
Jungwee Park
W
ork stress is defined as the harmful physical and emotional responses that occur when job requirements do not match the worker’s capabilities, resources, and needs (National Institute of
Occupational Safety and Health 1999). It is recognized world-wide as a major challenge to individual mental and physical health, and organizational health (ILO
1986). Stressed workers are also more likely to be unhealthy, poorly motivated, less productive and less safe at work. And their organizations are less likely to succeed in a competitive market. By some estimates work-related stress costs the national economy a stag-gering amount in sick pay, lost productivity, health care and litigation costs (Palmer et al. 2004).
Work stress can come from a variety of sources and affect people in different ways. Although the link between psycho-social aspects of the job and the health and well-being of workers has been well documented
(Dollard and Metzer 1999), limited work has been done on the effects of distinct stressors on job per-formance. As well, various protective factors can pre-vent or reduce the effects of work stress, and little research has been done toward understanding these mitigating individual and organizational factors.
One important source of work stress is job strain.
According to the demand/control model (Karasek
1979), job strain is determined by the interactions between psychological demands and decision latitude
(see Work stress). The first dimension, the psychologi-cal demands on the worker, relate to pace and inten-sity, skills required, and the ability to keep up with colleagues. The second dimension relates to the degree of creativity versus repetition, as well as the extent of freedom and responsibility to decide what to do and when to do it (Lindström 2005). Four work environments can then be derived: high-strain jobs, active jobs, low-strain (relaxed) jobs, and passive jobs
(see Psychological demand/decision latitude model).
Though simple identification of low- and high-strain jobs may be important, the distinction between job control and psychological demands must be retained because each category can have different effects on workers and their organizations. For instance, when job control is high and psychological demands are also high, learning and growth are the predicted behav-ioural outcomes. Much of the energy aroused by job challenges can be translated into direct action—effec-tive problem solving—with little residual strain. The growth and learning stimuli are conducive to high pro-ductivity. On the other hand, low demand and low control lead to a very unmotivating job setting, which results in gradual loss of previously acquired skills
(Karasek 1998).
Low-strain
Active
Passive
High-strain
High
Low
Learning
motivations to develop new behavior patterns Risk of psycho-logical strain and physical illness Decision latitude (control)
Psychological demand/decision latitude model
Psychological demands
High Low
Work stress and job performance
December 2007 Perspectives 6 Statistics Canada — Catalogue no. 75-001-XIE
Work stress
To measure work stress, the CCHS and NPHS used an abbreviated version of Karasek’s Job Content Question-naire (JCQ) (Karasek 1985). The CCHS measured work stress of respondents working at jobs or businesses in the past 12 months, while the NPHS measured work stress of those employed at the time of the survey. Twelve items in the JCQ are used to measure job control, psychologi-cal demands, job insecurity, physical exertion and workplace social support. Each item is scored using a five-point Likert scale from strongly agree to strongly disagree
(items 4 and 7 are reverse scored):
Item Subscale
1. Your job requires that you learn new things. control
2. Your job requires a high level of skill. control
3. Your job allows you freedom to decide how you do your job. control
4. Your job requires that you do things over and over. control
5. You have a lot to say about what happens in your job. control
6. Your job is very hectic. demands
7. You are free from conflicting demands that others make. demands
8. Your job security is good. job insecurity
9. Your job requires a lot of physical effort. physical exertion
10. You are exposed to hostility or conflict from the people you work with. social support
11. Your supervisor is helpful in getting the job done. social support
12. The people you work with are helpful in getting the job done. social support
Based on scores from the psychological demands and job control items, four psycho-social work conditions are iden-tified: active (above median on both demands and control), high job strain (above median on demands, below median on control), low job strain (below median on demands, above median on control) and passive (below median on both demands and control). Respondents who disagreed or strongly disagreed with the security statement were classified as having job insecurity. Respondents who agreed or strongly agreed with the physical exertion state-ment were classified as having physically demanding jobs.
Respondents were classified as having low workplace so-cial support if they either agreed or strongly agreed with the first social support statement, disagreed or strongly disagreed with the second, or disagreed or strongly disa-greed with the third.
Additionally, respondents were asked if they were very, somewhat, not too or not at all satisfied with their jobs.
Those not too satisfied or not at all satisfied were clas-sified as having job dissatisfaction. Self-perceived work stress at the main job or business in the past 12 months was measured by asking: “Would you say that most days at work were: not at all stressful? not very stressful? a bit stressful? quite a bit stressful? extremely stressful?”
Respondents answering quite a bit or extremely were classified as having high self-perceived work stress.
Job strain is only one stressor workers may face at the workplace. Physical exertion and job insecurity can also cause stress. Even in an era of increasing high-tech information industries, the physical demands of work are still relevant and important to many. Being seri-ously concerned about physical exertion of work can become a stressor. This is related to concerns about physical hazards and work injuries. Undoubtedly, uncertain job security and the fear of layoff is also an important source of psychological stress for some, especially during times of economic contraction
(Williams 2003).
In addition, job satisfaction and self-perceived work stress can show different, yet important, aspects of job stress. Although these two may not identify specific sources of work stress, they show to what extent workers are dissatisfied with their jobs and perceive their daily work as stressful. Thus, many distinct sources and dimensions of work stress that could negatively affect some people can be identified. This article investigates levels, sources and effects of work stress for different socio-demographic and occupational groups. The 2002 Canadian Community Health Survey
(CCHS) and various cycles of the National Population
Health Survey (NPHS) are used to examine work stress and its effect on Canadian workers (see Data sources). First, the article describes work stress levels of employed persons aged 15 to 75 by selected charac-teristics. Second, cross-sectional and longitudinal analy-ses examine how work stress factors are associated with current and long-term productivity in terms of reduced work activities, disability days, and absence or separation from work. Multivariate techniques are used to control for employment characteristics and protective factors such as social support and individual coping behaviours (see Job-related variables and Social support and coping behaviours ). Social support buffering
Work stress and job performance
December 2007 Perspectives 7 Statistics Canada — Catalogue no. 75-001-XIE
Data sources
The cross-sectional analysis on work stress is based on the Canadian Community Health Survey (CCHS): Men-tal Health and Well-being, which was introduced in May
2002 and conducted over eight months. The survey cov-ered almost 37,000 people aged 15 or older living in private dwellings in the 10 provinces. Most interviews (86%) were conducted in person; the remainder, by telephone.
Respondents were required to provide their own informa-tion—proxy responses were not accepted. The survey response rate was 77%.
The longitudinal analysis is based on the National Popu-lation Health Survey (NPHS). The NPHS, which began in
1994/95, collects information about the health of Cana-dians every two years. It covers household and institu-tional residents in all provinces and territories. In 1994/
95, about 20,000 respondents were selected for the lon-gitudinal panel. The response rate for this panel in 1994/
95 was 86.0%. Attempts were made to re-interview these respondents every two years. The response rates for subsequent cycles, based on the original respondents, were 92.8% for cycle 2 (1996/97), 88.3% for cycle 3
(1998/99), 84.8% for cycle 4 (2000/01), 80.5% for cycle
5 (2002/03), and 77.4% for cycle 6 (2004/05). This analy-sis uses the cycle 6 longitudinal square file, which con-tains all responding members of the original panel regardless of whether information was obtained in all sub-sequent cycles.
0
10
20
30
40
Active High strain Low strain Passive
*
*
*
*
%
Psycho-social work conditions
Men
Women
Chart A More employed women reported high job strain than men
* significantly different from men
Note: Employed population 15 to 75, Canada excluding Territories.
Source: Statistics Canada, Canadian Community Health Survey, cycle 1.2, 2002. may depend on support from co-workers and super-visors as well as personal sources. Personal coping mechanisms may play an important role in controlling effects of work stress.
To account for survey design effects, the bootstrap technique was used to estimate coefficients of varia-tion and p-values and to perform significance tests.
The significance level was set at 0.05.
More work stress among women
Proportionately more employed women reported greater work stress than men—28% had high-strain and 17% had low-strain jobs, compared with 20% and
24%, respectively, for men (Chart A). Men were more likely to have active jobs than women. Small, but sig-nificant, differences were also found for self-perceived work stress (Chart B). One-third of women felt quite a bit or extremely stressed most days at work, com-pared with 29% of men. According to a multivariate analysis, employed women were 1.2 times more likely to report high self-perceived work stress, even after controlling for other socio-demographic and employ-ment-related factors (data not shown).
0
10
20
30
40
50
Physical exertion Job insecurity Job dissatisfaction High self-perceived stress *
*
%
Other work stress indicators
Men
Women
Chart B Employed women were more likely to report high work stress
* significantly different from men
Note: Employed population 15 to 75, Canada excluding Territories.
Source: Statistics Canada, Canadian Community Health Survey, cycle 1.2, 2002.
Work stress and job performance
December 2007 Perspectives 8 Statistics Canada — Catalogue no. 75-001-XIE
Table 1 Work stress indicators
Psycho-social work conditions Physical Job Job High self-exertion inse- dissatis- perceived
Active High Low Passive curity fa ction work strain strain stress
%
Age
15 to 24 8.1* 28.0
(
*
)
14.2
(
*
)
49.7* 52.8* 13.4 14.4
(
*
)
21.1*
25 to 39 26.1 24.6 21.4 28.0 44.2 15.6 10.4* 32.0*
40 to 54 (ref) 27.5 23.7 21.3 27.4 42.1 15.2 7.8 35.8
55 to 64 21.1* 19.5
(
*
)
26.1* 33.3* 38.5
(
*
)
13.2 5.6
(
*
)
29.2*
65 and over 13.6* 10.2*
E
32.5* 43.8* 31.0* 11.2
E
3.9
(
*
)
14.7*
Personal income
Less than $20,000 9.4* 27.6* 13.6* 49.4* 51.9* 19.4* 13.3* 22.2*
$20,000 to $59,999 22.9* 25.5* 22.3
(
*
)
29.4* 44.3* 13.7* 9.0* 32.3*
$60,000 or more (ref) 34.8 18.0 24.9 22.3 36.4 11.8 5.0 36.0
Education
1
Less than high school graduation 12.1* 24.4
(
*
)
16.7* 46.8* 63.0 * 13.9 8.8 26.0*
High school diploma 19.0* 27.8* 17.0* 36.2* 49.3* 13.2* 8.3 29.7*
Some college/university 20.1* 25.5
(
*
)
21.5* 33.0* 41.1* 17.3 8.8 29.6
(
*
)
Bachelor’s or higher (ref) 31.9 21.2 25.4 21.5 35.1 15.6 8.4 36.0
Marital status
1
Married (ref) 26.4 22.3 23.2 28.2 42.0 13.9 7.6 33.0
Never married 23.7* 26.0
(
*
)
20.3* 30.0 43.4 18.7* 12.5* 30.1*
Divorced, separated, widowed 24.7 26.8
(
*
)
17.8* 30.8 42.6 18.9* 9.7* 37.0
(
*
)
Student status
Yes 11.8
(
*
)
26.2
(
*
)
15.3
(
*
)
46.6
(
*
)
45.4 14.3 14.1
(
*
)
23.4
(
*
)
No (ref) 24.3 23.7 21.7 30.3 44.0 14.8 8.8 32.0
Shift work
Yes 16.2* 29.4* 16.4* 38.1
(
*
)
54.4* 15.3 11.5* 28.7
(
*
)
No (ref) 25.3 21.7 22.7 30.3 39.5 14.4 8.7 31.5
Self-employment
Yes 28.1* 13.7* 34.1* 24.2* 46.0 17.8* 4.8* 29.5
No (ref) 21.3 26.2 18.1 34.4 43.9 14.1 10.5 30.9
Full-time work
Yes 25.5* 23.8 21.7
(
*
)
29.0* 44.3* 14.2
(
*
)
9.4 33.0*
No (ref) 8.4 25.2 15.9 50.5 43.5 16.6 10.8 19.4
Occupation
White-collar (ref) 34.6 20.0 25.2 20.2 24.9 13.4 7.7 38.1
Sales and service 10.9* 31.1* 13.8* 44.3* 50.0* 15.4
(
*
)
13.0* 25.9*
Blue-collar 12.3* 24.5* 19.5* 43.7* 72.8* 15.0 10.7* 23.3*
* significantly different from reference group (ref) (p