1. Journal of Occupational Health Psychology Copyright 1998 by the Educational Publishing Foundation
1998, Vol. 3, No. 4, 322-355 1076-8998/98/$3.00
The Job Content Questionnaire (JCQ):
An Instrument for Internationally Comparative
Assessments of Psychosocial Job Characteristics
Robert Karasek Chantal Brisson
University of Massachusetts Lowell Laval University
Norito Kawakami Irene Houtman and Paulien Bongers
Gifu University National Institute for Work and Health
Benjamin Amick
New England Medical Center
Part I discusses the Job Content Questionnaire (JCQ), designed to measure scales assessing
psychological demands, decision latitude, social support, physical demands, and job insecurity.
Part II describes the reliability of the JCQ scales in a cross-national context using 10,288 men and
6,313 women from 6 studies conducted in 4 countries. Substantial similarity in means, standard
deviations, and correlations among the scales, and in correlations between scales and demographic
variables, is found for both men and women in all studies. Reliability is good for most scales.
Results suggest that psychological job characteristics are more similar across national boundaries
than across occupations.
This article consists of three parts. Part I introduces Part II reports the cross-national validity, for men
the Job Content Questionnaire (JCQ) as a tool for and women, of the JCQ scales in six broadly
psychosocial job assessment. First, a description of representative populations from four advanced indus-
scales and their underlying theoretical concepts is trial societies: the United States, Canada, the
presented. This is followed by a discussion of Netherlands, and Japan. JCQ scale means, standard
empirical issues in the development of the question- deviations, reliabilities, and correlations are com-
naire and its validity. Part I concludes with a pared. Part III reviews comparison of the intercountry
discussion of measurement issues, administrative and interoccupation differences in the scales, dis-
issues, and future challenges. cusses specific scales issues, and discusses the
implications of the study for interpretation of
psychosocial job assessment questionnaires.
Robert Karasek, Department of Work Environment,
University of Massachusetts Lowell; Chantal Brisson, PART I
Department of Preventive and Social Medicine, Laval
University, Quebec City, Quebec, Canada; Norito Kawakami,
School of Medicine, Department of Public Health, Gifu The Job Content Questionnaire (JCQ):
University, Gifu, Japan; Irene Houtman and Panlien
Bongers, National Institute for Work and Health, Amster- Psychosocial Job Assessment Instrument
dam; Benjamin Amick, The Health Institute, New England
Medical Center, Boston. Instrument Overview
The Job Content Questionnaire (JCQ) is copyrighted.
Users should request the instrument from the JCQ Center The JCQ is a self-administered instrument de-
(see the JCQ UsagePolicy section). The JCQ is provided signed to measure social and psychological character-
with research documentation to most users free of charge,
but commercial and very large research projects pay a usage istics of jobs. The best-known scales--(a) decision
fee to support comparative reliability analysis and instru- latitude, (b) psychological demands, and (c) social
ment development on a nonprofit basis through the JCQ support--are used to measure the high-demand/low-
Center, University of Massachusetts Lowell. control/low-support model of job strain development.
Correspondence concerning this article should be ad- The demand/control model predicts, first, stress-related
dressed to Robert Karasek, Department of Work Environ-
ment, University of Massachusetts, Lowell, Massachusetts risk and, second, active-passive behavioral correlates of
01854. jobs. Other aspects of work demands are assessed as well:
322

2. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 323
(d) physical demands and (e) job insecurity. The psychological strain occur when the psychological
instrument has a recommended length of 49 questions. demands are high and the worker's decision latitude
All scales can be used for microlevel, job- is low: job strain. Low social support at work further
characteristic analytic purposes, such as assessing the increases risk. A second set of hypotheses, related to
relative risks of individuals' exposures to different what might be called good stress, involves active
work settings to predict job-related illness develop- behavior development under conditions of high
ment, psychological distress, coronary heart disease, demands and high decision latitude, which predict
musculoskeletal disease, and reproductive disorders. motivation, new learning behaviors, and coping
The scales also allow testing of hypotheses about pattern development (of course, the active behavior
activation, worker motivation, and job satisfaction hypotheses are contingent on demands not being too
and have been used for such studies. The conceptual high). The reverse is predicted for low demands
framework underlying the JCQ allows its application coupled with low decision latitude: a very unmotivat-
in social policy as a measure of work quality ing job setting leading to negative job learning or
(Karasek, 1998), in addition to the more commonly gradual loss of previously acquired skills.
assessed work quantity issues: wages, hours, and A dynamic version of the model integrates the job
benefits. Broader economic development issues of strain and active behavior hypotheses with personal-
skill utilization as well as social costs of market-based ity characteristics measuring accumulated strain and
economic development are beginning to be addressed self-esteem development (Karasek & Theorell, 1990)
(Karasek & Theorell, 1990) using the instrument. No with the goal of predicting strain development and
personality orientation scales or measures of non-job learning over time. The model is based on measures
stressors are included--two areas in which the user of psychological demands of work combined with a
may want to supplement the instrument. measure of task control and skill use (decision
The JCQ has been translated into over a dozen latitude). The psychological demand dimension re-
languages. The instrument is nationally standardiz- lates to "how hard workers work" (mental work load;
able by detailed occupation in several countries, Meshkati, Hancock, & Rahami, 1990), organization
providing an occupational scoring system. An active constraints on task completion, and conflicting
users' group supports usage of the JCQ, and an demands. It includes subscales shown in Table 1
international board of researchers decides on policy (Subscales 2a, 2b; see Karasek & Theorell, 1990).
and development issues. The "recommended version" includes additional
specific measures of cognitive workload (Subscaies
2c, 2d).
JCQ Scales and Their Theoretical Bases
The JCQ arose out of the adaptive response to
serve the new empirically based areas of social Scales la and lb: Components of Decision
epidemiology, behavioral medicine, and psychosocial Latitude--Skill Discretion and Decision
job analysis, requiring a multidisciplinary theoretical Authority
model. Because the primary theoretical model upon
which the JCQ is based and discussions of alternative The worker's control over the performance of his
scale formulations in its domain are extensively or her own job is measured by two theoretically
reviewed elsewhere (de Jonge & Kompier, 1997; distinct subdimensions of decision latitude that are
Karasek, 1979, 1997; Karasek & Theorell, 1990; usually highly correlated: skill discretion and deci-
Kristensen, 1995, 1996; Landsbergis, SchnaU, War- sion authority (Karasek & Theorell, 1990). Skill
ren, Schwartz, & Pickering, 1994), this article only discretion (Subscale la) is measured by a set of
presents outlines of those arguments by way of an questions that assess the level of skill and creativity
introduction to the JCQ scales. required on the job and the flexibility permitted the
worker in deciding what skills to employ (similar to
variety; e.g., Hackman & Lawler, 1971). A second
Scale 1: Decision Latitude and Scale 2: subdimension, decision authority (Subscale lb),
Psychological Demands assesses the organizationally mediated possibilities
for workers to make decisions about their work
The most commonly used demand/control model (autonomy; e.g., Hackman & Lawler, 1971). A
hypothesis (Karasek, 1979, 1997; Karasek & Theo- question on skills required by the job allows
rell, 1990) predicts that the most adverse reactions of assessment of skill underutilization (Subscale lc). A

3. 324 KARASEK El" AL.
Table 1
Scales and Numbers of Questions in the Full Recommended JCQ and the "Core QES"
Scale Core QES JCQ Full recommended JCQ
1. Decision latitude
a. Skill discretion 6 6
b. Decision authority 3 3
c. Skill underufilization 2b 2b
d. Work group decision authority (new) 3
e. Formal authority (new) 2
f. Union/representative influence (new) 3
2. Psychological demands and mental workload
a. General psychological demands 4 5
b. Role ambiguity 1 1
c. Concentration (new) 1
d. Mental work disruption (new) 2
3. Social support
a. Socioemotional (coworker) 2 2
b. Instrumental (coworker) 2 2
c. Socioemotional (supervisor) 2 2
d. Instrumental (supervisor) 2 3
e. Hostility (coworker) (new) 1
f. Hostility (supervisor) (new) 1
4. Physical demands
a. General physical loading 1 1
b. Isometric load (new) 2
c. Aerobic load (new) 2
5. Job insecurity
a. Generaijob insecurity 3 4
b. Skill obsolescence (new) 2
Total que~ions 27 49
Note. JCQ = Job Content Questionnaire; QES = Quality of Employment Surveys.
a Eight new scales/dimensions and additional items were added to make the Recommended JCQ format. b Education was
also used in this scale.
third, macrolevel component of decision latitude high demand and high control, has high-prestige
assesses the possibility of participatory influence on occupations: public officials, physicians, engineers,
organization level issues, as well as union and nurses, and managers of all kinds. The passive job
work-group participation (Subscales ld, le, If). quadrant (lower left), with low demands and low
The JCQ integrates use of both individual and control, has clerical workers such as billing clerks,
occupation-based conceptions of job characteristics. and low-status service personnel such as janitors. The
The occupation-based job characteristic assessments high-strain quadrant (lower right), with high demands
yield an effective communication tool for interpreting and low control, has machine-paced operatives such
the meaning of the otherwise abstract psychosocial
as assemblers, cutting operatives, freight handlers, as
JCQ scales in terms of specific jobs situations, and
well as other low-status service operatives such as
provide a source of validating information about job
waiters. Occupations with high percentages of
situations. As an example: When the two JCQ job
women are frequent (garment stitchers, waitresses,
characteristic scales---decision latitude and psycho-
logical demands--are arrayed as a four-quadrant telephone operators, and other nurse's aides). Low-
diagram, they define the strain and active behavior strain self-paced occupations (upper left) often
hypotheses of the demand/control model. These can involve significant training and self-pacing, such as
be used to display (see Figure 1) average job repairmen, linemen, and natural scientists. Kristensen
characteristics of occupations in U.S. Census occupa- (1996) reconceptualized the four quadrants above
tion codes and the U.S. Quality of Employment respectively as qualified work, surveillance work,
Surveys (QES) database (Karasek & Theorell, 1990). tempo work, and craftsman's work. Kristensen
In Figure 1, the active job quadrant (upper right) with identified the linkages to structural and technological

4. Decision l
L'tit:dAichite_Lc
t
Engineer
• Natural Programmer Farmer
O
Scientist • ~]~ Teacher--H.S.
• Publc
WIFManager-trade
• Officials • Physician
+0.50 Bank Officer
• Lineman • Clerk
• Foreman Supervisor
O Repairman..~ O Nurse
I I
o_Machinist • Carpenter
050
/
+0.5~
Psychological
Demands
k-
1
I I I il~ Fireman
t
Stationary • Health • Off. Computer
• EngineerA~ I Technician Operator
_ WBilling Clerk
~lhDeliveryman
• Watchman WSales Clerk
I
• Dispatcher
-0.5o-
• Gas Station
O Janitor Attendant
• Cutting tWaitress
• Miner - OperativeO Nurse's Aide
O • Freight handler
Construction • Telephone
Laborer Operator/,f--~
" " Keypuncher / Si t n t ~
~ /Gm a '~gh O
ae
r~
stitcher,-,,~.,~
O Assembler-
electric/trans, mfg.
Figure I. The occupational distribution of psychological demands and decision latitude
(U.S. male and female workers; N = 4,495). From "The Political Impfications of Psychosocial
Work Redesign: A Model of the Psychosocial Class S~ucture" (p. 177), by R. A. Karasek, in
J. V. Johnson and G. Johansson (Eds.), The Psychosocial Work Environment: Work
Organization, Democratization, andHealth, 1991, Amityville, N-Y:Baywood. Copyright 1989
by Baywood Publishing Company. Reprinted with permission.

5. 326 KARASEK ET AL.
developments in production processes, thus making it the Job Insecurity Scale section) because specific
more useful in job redesign contexts. events of unemployment are relatively low frequency,
even when the fear of job insecurity can be more
Scale 3: Social Support widely experienced (Subscale 5a). The job insecurity
effect can depend on the labor market requirements
The demand/control model has been expanded by for particular skills, limiting future career develop-
Johnson (Johnson, 1986; Johnson & Hall, 1988) with ment possibilities (Subscale 5b).
the addition of social support as a third dimension.
The primary hypothesis, that jobs which are high in
Theoretical Interpretation of Scales
demands, low in control, and also low in social
support at work carry the highest risk of illness, has
and Implications: Sociological
been empirically successful in a number of chronic and Psychological Origins
disease studies (Johnson, 1989; Karasek & Theorell,
The JCQ provides advantages to researchers by
1990). Karasek and Theorell (1990), Karasek, Trian-
integrating strengths of multiple disciplines. How-
tis, and Chaudhry (1982), and Johnson and Hall
ever, it also presents the JCQ users with the challenge
(1988) discussed the differential impacts of support
of reconcifing multiple scientific literaanes when findings
from coworkers and from supervisors and, within
are reported. We briefly outline major linkages below.
these, the separate impacts of instrumental and
The primary hypotheses of the JCQ, resulting from
socioemotional support, respectively (Subscales 3a,
the demand/control model, are both psychological
3b, 3c, 3d). Interpersonal hostility is also included as a
and sociological in nature and methodology. The JCQ
measure of social support deficit (Subscales 3e, 3f). The
is sociological in that it presumes existence of
social support addition acknowledges the need of any
socially "objective" environments that systemati-
theory of job stress and behavior development to assess
cally affect individual well-being and behavior. There
social relations at the workplace.
is a focus on (a) major social institutional settings, (b)
broad population groups, (c) covariance of measures
Scale 4: Physical Demands with major demographic categories, and (d) its
hypotheses, which evolved from sociological life
The "demanding costs" of work activity are not stress and illness as well as work alienation traditions.
just mental but also physical. Indeed, the more Also, consistent with much sociological literature,
traditional concept of workloads involves physical associations are usually controlled for social class (for
loads. Physiological effects of stress on the cardiovas- contrasting perspectives, see Ganster & Schaubroeck,
cular system, the effectiveness of mental functioning, 1991; Karasek & Theorell, 1990).
and general fatigue are shown in much research However, there are also differences with classic
literature to depend on both mental and physical sociological approaches. The JCQ is based on a
loads, and thus this measure is also included in the theoretical foundation that implies an alternative,
JCQ. Although the original QES questionnaire psychosocial class model, which appears to predict
contains only a single item on physical exertion health outcomes more effectively than the conven-
(Subseale 4a), the recommended form of the JCQ tional class model (Karasek, 1997, 1998; Karasek &
includes static (Subscale 4b) as well as dynamic Theorell, 1990, chapters 5, 9, 10). Kristensen (1996)
physical loads (Subscale 4c), both shown to be and Karasek and Theorell (1990) noted that the scales
important for musculoskeletal disorder development. and methods also lend themselves to understanding of
the social and technological structure of production
Scale 5: Job Insecurity processes. Such associations allow interpretation of
JCQ findings for human capital and economic
Work's psychological burden consists not only of development studies.
the work of carrying out the task but also in the A variety of methodological techniques from both
human costs of adapting to labor market dynamics. sociology and psychometrics are used: scale reliabil-
These have become increasingly important in the last ity analysis, scale construction techniques, multilevel
several years, because the global economy has had causal analyses, and data reduction techniques such
job-displacing effects in many countries and in- as factor analysis. The JCQ uses sociological
creased reported job insecurity (Lohr, 1996). Measure- questionnaire assessment methods to collect valid
ment of these items poses statistical challenges (see data on social environments. The JCQ occupation

6. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 327
approach uses the worker's occupation as an alterna- Empirical Basis of JCQ Scale Development
tive unit of analysis to the individual's own job
reports, allowing linkage to other insights available Origin: Stage IfPre-1984
for occupational experience.
The JCQ has developed in stages. Historically, the
The JCQ also reflects a psychological focus and is
origin of the instrument, which predates the "recom-
probably used more often by psychologists than by
mended version JCQ" in 1985, involved analyses of
sociologists. It addresses classic psychological topics
broad pools of job characteristic survey data in two
such as the behavioral basis for emotion-driven
countries. The core questions for the JCQ scales are
psychological distress, psychosomatic illness develop-
taken from the three nationally representative samples
ment, and changes in microlevel behavior related to of the much analyzed QES gathered by the University
social situations. There is a presumption that psycho- of Michigan Survey Research Center in 1969, 1972,
social experiences are a major determinant of health and 1977 for the U.S. Department of Labor. Each of
and well-being, mediated by the neurophysiological the three QES surveys was eclectically designed and
mechanisms, as well as behavioral pathways. surveyed over 1,000 aspects of work experience, in a
Psychologically, the JCQ--demand/control method manner often using different questions from survey to
reflects a stimulus approach, as opposed to a survey. Our research group (Karasek et al., 1988;
relational approach, which emphasizes personal Schwartz, Pieper, & Karasek, 1988) conducted
cognitive interpretation of the person-environment extensive statistical analyses, analyses of theoretical
relationship. The JCQ assumes that behavior is, to a coherence, and analyses of individual questions
significant extent, generated by social environments predicting efficiency for these large groups of
and their constraints outside the individual. The questions in the early 1980s. These confirmed that
cognitive psychological claim that decision choices major aspects of the core content of the psychosocial
constitute the primary mental workload is contrary to work experience could be captured by the small
the demand/control hypothesis that social demands number of QES questions. On this basis, a small
are moderated by the behavioral degree of freedom subset of the questions was selected to create the Job
that decision opportunities present (Karasek, 1997). Characteristic Linkage System (Schwartz et al.,
The JCQ-demand/control approach also often treats 1988). Approximately two thirds of the linkage
emotional response as a dependent variable derived system questions were sufficiently similar (with
from work-related behaviorial requirements. minor adaptations and corrections) across the years to
There are also significant congruencies with yield common assessment of absolute scale scores: a
psychophysiology, as well as some differences in QES-based JCQ "core" (see Table 1, column 2). The
focus. Most previous stress theories were developed three QES survey question sets had 27 questions in
to describe reactions to "inevitable" acute stress in common in the psychosocial area, which allowed
development of a pooled sample of all 4,900
situations threatening biological survival (Cannon,
respondents, still by far the largest nationally
1914; Seyle, 1936/1976). The demand/control model
representative U.S. data set on psychosocial job
was, however, developed for work environments in
characteristics. This core serves as the source of
which stressors are chronic, not initially life threaten-
standard score data for JCQ occupational mean scores
ing, and are the products of sophisticated human
and a basis for time-related comparisons in the scales
organizational decision making. The controllability of (statistical reliability is discussed in Karasek &
the stressor was found to be important and appears to Theorell, 1990, Appendix 1).
have become even more important as we develop The validation for the utility of such scales was
even more complex demands and limitations on also developed from a similar set of questions in
individual behavior. However, significant consistency longitudinal, Swedish nationally representative data-
with classic psychophysiology is demonstrated by bases, which could be analyzed extensively for
Frankenhaeuser and Johansson's (1986) psychologi- covariations with other social and individual data
cal research, which shows the congruence of two (Karasek, 1976, 1979; Karasek & TheoreU, 1990) and
primary patterns of physiological response (adrena- which had extensive health outcome data. These
line related and cortisol related) with the main analyses, while confirming the demand/control model
hypotheses of the demand/control model--allowing utility, also illuminated the importance of demo-
linkage among physiological response, social situa- graphic, occupational, and social relations data, and
tion, and emotional response patterns. broadly assessed work demand and hazard data

7. 328 KARASEK ET AL.
(Karasek et al., 1981; Karasek, Schwartz, & Pieper, should assess a single underlying theoretical con-
1983) and implied that a future measurement struct. In JCQ design, true statistical reliability is
instrument should not be restricted to the demand/ sometimes balanced against a goal of a specific
control task questions alone. content interpretability. Thus, the scales are also
composed of subscales with separate interpretability
(see Table 1 and discussion above), a goal which
Stage II: JCQ Recommended Version--1985
competes with scale statistical reliability. The ques-
The next stage was the development of the JCQ tions should also be standardizable questions. The
Recommended Version 1.1 in response to request for JCQ has also had the goal of covering the most
an instrument to assess the psychosocial hypotheses important aspects of qualitative work situations with a
and demand/control models. This is the current small enough number of scales that the interactions
version of the instrument. The design of the current between the scales can be feasibly examined.
JCQ was initiated by request from the U.S. National
Heart, Lung and Blood Institute's request for scales
Toward "Objective "Assessment:
for the U.S. Framingham Offspring Study. The JCQ
Rating Versus Evaluation
authors were aware of the length limitations posed by
research teams in national survey designs and the An important goal of the JCQ is gathering
hesitancy of other researchers adopting question sets "objective" data about work environments relevant
not of their own design, thus, the design of the new for prevention-oriented goals of improving social and
JCQ instrument in 1984 focused on a very short, psychological working conditions. The Swedish
efficient questionnaire that could be self-administered Level of Living Survey (Johansson, 1971) was a
in 15 rain, with minimal participant guidance. methodological guide: The bias in the questionnaire
The original QES core was not theoretically precise response by the participant, while inevitable, was
in several areas (particularly psychological and designed to be minimized. The questions are designed
physical demands). To add precision to the theoretical to report about, but not evaluate, the participant's
constructs of the QES core, to expand theoretical usual or main job. Thus, the JCQ questions use simple
coverage of both psychological and physical de- language so there are meaningful responses possible
mands, to expand job insecurity and social support by all employed respondents, presented in a language
scale coverage, and to assist in discriminant validity, simple enough to be understood by participants at all
we included additional newly drafted questions (see education levels. The response set is designed to
Table 1, column 1) to the QES questions, yielding the assess the validity of the statement about the work
present set of scales used in the JCQ data sets. These environment on a 4-point scale, facilitating the
expansions formed the Recommended JCQ Instru- similar quantitative weighting of questions.
ment Version (see Table 1, column 2), with 49 Use of participants' own questionnaire reports
questions, which is the most commonly used version about their jobs, of course, automatically introduces
(14 additional new questions and 8 additional QES self-perceptions--the source of the major critique of
questions had been added beyond the original core). validity of instruments such as the JCQ (see the
Additional question sets cover physical work hazards, Implication for Broad Interpretability of Psychoso-
computer interfaces, customer interaction, and psycho- cial JCQs section). In many cases, self-reports on job
logical strain scales. An update of the recommended conditions are the only feasible information-gathering
version in 1995 (Version 1.5) included pilot versions strategy about workers' detailed social working
of a set of global economy questions and more conditions. For example, it would take an outside
standardizable psychological strain scales. observer much time to understand the social support
situation of the worker. Frese and Zapft (1988)
JCQ Focus and Scale Design Criteria claimed that the risk of self-report bias depends on the
degree to which the questions require a complex
The multiple goals underlying JCQ construction burden of evaluative cognition by the participant. The
introduce competing design criteria: (a) standard JCQ objective assessment goal means that the
scale reliability assessment, (b) coverage breadth, (c) questions attempt to minimize this self-reflexive
scale length economy, (d) scale number economy, and component: They report about jobs, but minimize
(e) specific content interpretability. A pure concept of evaluation of them. Questions of the type "lack of
statistical reliability means that a set of questions decision making is important for me" and "the time

8. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 329
pressures are too much for me" are replaced by The same occupational basis that provides the
questions that emphasize simple assessments of standardized scores is also the basis of an often
environmental conditions only, such as: "I have utilized occupational score linkage system (Schwartz
freedom to make decisions about my job" and "My et al., 1988). The JCQ job characteristic scales can be
job requires I work fast." Such linguistic distinctions linked to other databases through U.S. three-digit
have been considered quite significant in other census occupation codes (1970) and also to four-digit
psychological research contexts: for example, state- U.S. Standard Industrial Classification (industry
trait response differentiations based on phrasing classification) codes. This database linkage system
differences such as "Today I feel angry" versus "I allows psychosocial job content scores to be associ-
usually feel angry." ated with health and productivity outcomes in
Sources of difficulty remain, however. Self- national or company databases already in existence
reflexive judgments remain in two psychological (such as U.S. Census, Commerce, or U.S. National
demand questions: "work hard" and "work fast" (see Center for Health Statistics data), for which direct
Appendix A). Also, the JCQ goal of broad coverage questionnaire data collection would not be feasible.
on jobs characteristics with a short set of questions
means that many questions elicit summary judgments
Aggregate Scoring Methods for Work Groups
about some quality of the job (skill requirements,
decision possibilities). Questions about more specific Bias of findings could potentially occur with
job situations could avoid this problem, but would self-reported psychosocial work environment and
likely make the questionnaire longer or the questions dependent variables such as depression, exhaustion,
unjudgable by some respondents, and therefore the and dissatisfaction (see the Implications for Broad
responses difficult to compare across groups. Interpretability of Psychosocial JCQs section). One
remedy is to aggregate self-report responses by work
groups with similar work situations, thus diluting
Occupation-Based Analysis
individual biases (Kristensen, 1996). This is, of
and Score Standardization course, the basis of the occupation database linkage
In addition to direct administration of JCQ system suggested above, but systems of mixed
questionnaires to workers, the JCQ system offers a self-report and work-group aggregated assessment
second set of occupation-based methodologies. There have also been successfully applied (Vahtera, Pentti,
is an extensive system of JCQ scores scales by & Uutela, 1996).
detailed occupation and gender in several countries The alternative of expert observations is certainly
that is the basis of (a) the JCQ occupational score theoretically desirable, but in practice it has problems.
standardization system and (b) the occupational Expert observations are costly, time consuming, and
linkage system. in assessment of social interactions do not obviously
Detailed scoring procedures for the JCQ scales are generate more accurate measures resulting in low
described in the JCQ Questionnaire and User's Guide interrater reliability. There are also theoretical biases
(Karasek, 1985). Most of the scales have been involved in the very concept of standard "expert"
standardized by detailed occupation codes for several measures: It is much easier to measure the easily
national populations (for the U.S. population: Karasek observed, repetitive quality of the low-status assembly-
& Theorell, 1990, Appendix; Schwartz et al., 1988; line jobs than the diverse tasks of nigh-status
with related scales standardized in Sweden [work managers or professionals. Thus, measurement reli-
exposure matrix: Johnson & Johansson, 1991; ability for the most potent set of psychosocial job
Johnson & Stewart, 1993]). The JCQ questions can be characteristics (decision latitude, skill, and decision
compared to national scale scores for detailed census autonomy) is probably correlated with scale level--a
code by sex and by four-digit industry code. This complex confounding of content and validity (for all
allows unique assessment of differences between a methodologies, not just the JCQ).
target group and "national norms" for psychosocial
job dimensions. This allows JCQ users involved in Scale Statistical Validity
practically oriented job analyses, small populations,
or single-plant studies to compare their findings with The most substantial compilation of reliability
national averages on the scales (broken down by sex, findings is presented in the following section (Part II).
occupation, and industry). However, previous reliability analyses of the scales

9. 330 KARASEK ET AL.
very similar to the JCQ scales have been published update has cataloged 41 studies of the major coronary
for the U.S. national populations (Q.E.S. database: heart disease risk factors (blood pressure, serum
Karasek & Theorell, 1990, Appendix 1; Schwartz et cholesterol, and smoking) testing associations with
al., 1988). Kawakarni and Fujigaki (1996) and job strain. In over a dozen studies of blood pressure
Kawakami, Kobayashi, Araki, Haratani, and Furui using sophisticated ambulatory assessment technolo-
(1995) published the first studies on the reliability of gies, all show either positive or mixed positive
recommended format JCQ scales (omitting physical results. However, less-sophisticated blood pressure
demands and job insecurity). The study concluded measurement technologies show no consistent associa-
that the JCQ is reliable for Japanese populations and tions, and smoking and cholesterol have mixed
found Japanese occupation scale ratings that are positive and null associations.
similar to those in the United States (see Appendix A). Consistent associations between mental strain and
Brisson et al. (in press) showed JCQ scale reliabilities JCQ-like scales are also reported (see Bourbonnais,
to be good and confirmed the scale structure Busson, Moisan, & Vezina, 1996; Karasek &
(Larocque, Brisson, & Blanchet, in press) from both Theorell, 1990), but differential effects of job
random population survey and a white-collar survey characteristics are noted. Measures of exhaustion and
from Quebec, Canada. A 1993 large-scale sample in burnout are more consistently associated with high
the United States (Amick, Mangione, & Wu, 1998) psychological demands, whereas depression and
reported JCQ scales to be reliable, as well as scale anxiety measures are more strongly associated with
structure confirmation, but some scales differ signifi- low decision latitude.
cantly from the recommended JCQ format. Sante Occupational musculoskeletal injury prediction is
Quebec (1994) showed acceptable JCQ scale reliabili- reviewed by Bongers, de Winter, Kompier, and
ties in the Netherlands, but some factor structure Hildebrandt (1993), who found support for the
differences arose. predictive utility of the demand/control/support model,
particularly for upper extremity disorders. Many
additional studies using the demand/control model
Predictive Validity and JCQ scales have been undertaken since then,
including associations with pregnancy disorders
It is beyond the scope of this article to review the
(Brandt & Neilsen, 1992; Fenster et al., 1995)and
extensive research literature using the JCQ and
immune system disfunctions (Kawakami & Fujigaki,
JCQ-like scales to predict illness (much research is
1996; Peters et al., 1998).
based on similar, but not exactly equivalent scales).
Comprehensive reviews are presented by Marmot and
Theorell (1988), Kristensen (1989), Schnall and
JCQ Measurement and Administrative Issues
Landbergis (1994), Kristensen (1995), Kasl (1996),
and Tbeorell and Karasek (1996). However, in
summary, it can be stated that the JCQ scales and JCQ Administration
JCQ-like scales demonstrate substantial predictive
validity with respect to stress-related chronic disease The JCQ is designed for self-administration and
in international and U.S. research. has often been included as a section in other
Job strain and heart disease associations constitute questionnaire instruments in which a short introduc-
the broadest base of empirical support for the model. tory sentence about how to respond to the questions is
JCQ scales or similar scales associate significantly included. The completion time is short, approxi-
with cardiovascular mortality using a wide range of mately 15 min for the full recommended version.
methodologies. Landsbergis (augmenting his earlier Professional assistance, such as the research person
review [Schnall & Landsbergis, 1994] by personal reviewing the instructions, has also often occurred.
communication, December 1997) tabulated 72 pub- In addition to the standard JCQ questions, JCQ
lished studies of cardiovascular disease (CVD) or users are encouraged to add their own specific
CVD risk factors testing associations with job strain "umbrella questions" that refer to the measurement
using JCQ-like scales. Of the 36 studies investigating of specific job conditions in the surveyed work sites.
CVD or mortality, over two thirds showed positive Although the umbrella questions would differ be-
associations (i.e., either all significant or mixed tween studies, they could be factor analyzed with the
significant positive results) with job strain, and many other JCQ questions and correlated with the standard
of these were positive cohort studies. Landsbergis's JCQ scales used as reference points.

10. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 331
JCQ Breadth of Use and Scale Consistency back translation into English submitted to the JCQ
Center, and a copy of the translated instrument.
The instrument has been selected for large studies Adaptation of the JCQ for housework and home-
of job conditions in the United States, Canada, role work, student status, and unemployment has also
Europe, and Japan. The JCQ is being used by large been undertaken but presents challenges because
studies in Europe (over 50,000 participants) and these less-structured social roles mean less specific
Japan (over 40,000 participants) for the study of job questionnaire language. Adaptation of the JCQ for
strain, heart disease, and absenteeism. The short low-education workers and workers in less economi-
length and predictive validity appear to be the major cally developed countries for Spanish-speaking work-
reasons for its success. Length is mentioned as a ers has also been undertaken.
crucial instrument parameter by many users (a
substantial number would like an even shorter
instrument; there is no validated shorter instrument
JCQ Usage Policy
with standardizable scores at present). Because of the
The JCQ is copyrighted and not published in the
active international collaboration by JCQ researchers,
public domain; however, it is the goal of the JCQ
the effort invested bymany individual JCQ projects in
Center to make it available to all researchers who
the past is now yielding collective benefits with the
request it with substantial supporting documentation,
development of comparative databases that further
and to promote scientific development in the area
enhance the data interpretability of each study. through a users' network. The JCQ Questionnaire and
User's Guide and research documentation are pro-
JCQ Usage Study: Compliance vided free of charge to most users. However, JCQ use
With Recommended Format by large research studies (over 750 participants) and
commercial users requires payment of per-nse
The JCQ has retained the same recommended charges. Registration in a JCQ users' project database
format (Version 1.1) since 1985 (see Appendix C). To for the users' network for all users and a copy of the
test the consistency of scale use and to assess the researcher's JCQ and demographic data for future
utilization of the JCQ, in 1995 Robert Karasek reliability analyses (large studies only) are required.
conducted a survey of all contactable JCQ users. Contact the JCQ Center, Department of Work
From the 246 recorded requests, 130 projects were Environment, University of Massachusetts Lowell,
estimated to have been completed by that time. The Lowell, Massachusetts 01854, for details of policy,
most consistently used scales are the decision latitude fees, and requirements.
scales, with 85% reporting compliance with the
standard version. Psychological demands has 69%
Summary of lnstrument Description
using the recommended nine-question version and
another 19% using the older five-question (QES core)
and Notes on Future Challenges
version. Standard version social support was used To summarize description of the instrument, we
74% of the time. However, physical demands are include at this point several comments that reflect
included in only 58% of the studies and job insecurity information in the second, empirical section of this
in only 36% of the studies. The skill utilization article.
question, important for work quality policy and 1. The 1995 study of usage consistency demon-
productivity outcomes, is included in 42% of these strates that the JCQ has provided a common set of
studies. scales used with consistency throughout almost 100
studies, including large national studies, of psychoso-
Translations Into Other Languages cial factors at work. This breadth of use is a unique
occurrence for measurement of psychosocial work
Authorized translations of the full JCQ instrument characteristics in the United States and internation-
from English, which have been specifically approved ally, and it helps to overcome the major scientific
and which are available from the JCQ Center, are deficit of such instruments: the lack of comparative
French-Canadian, French-Belgium, Flemish-Bel- assessment capability across databases (see discus-
gium, Spanish, Swedish, Dutch, Italian, and Japanese. sion in Santer & Murphy, 1995).
Other language translations are in process. The 2. As a result of the empirical review in the
authorized process requires requesting permission, a following section (Part II of this article), the JCQ

11. 332 KARASEK ET AL.
recommended version since 1985 (and provisionally b. For psychological workload and social
augmented in 1995) remains the "recommended support, improved scale performance may require
version." The need to expand from the earlier "QES linguistic tool development and local consensual
core questions" is validated. In particular, some of validation of response meanings. Additional measure-
these additions are crucial for continued psychosocial ment methods beyond questionnaire use involving
research: Job insecurity is of increasing importance observations or interview methods that can be linked
because of the global economy, and the physical to the JCQ are also needed. Parts of these activities
demand scale is of increasing importance because of may involve establishing new languages for social
the increasing prevalence of musculoskeletal disor- policy purpose in these areas---a social advocacy task.
ders in many countries. The "skill level required" c. Dropout of highly "stressed" participants
questions (the seventh skill discretion question) is from studies, especially in more rigorous scientific
crucial for work-quality policy discussions. protocols, appears to be a much larger problem than
The predictive validity of the scales, while not previously assumed and is growing as stresses of
reviewed in detail in this article, is probably the major modern life make participation in scientific studies
reason for the success of the instrument. In general, it difficult for certain groups (temporary and transitional
can be concluded that the JCQ seems to be potentially employees, marginal economic groups in all settings,
useful in capturing important elements of psychoso- and many populations outside of the developed
cial experience at work in many countries, and thus industrial countries).
allows an internationally comparative understanding d. Organization-level job factors are also not
of "qualitative costs" and "benefits of work." studied in the JCQ, and their effects on determining
On the basis of the findings of the analysis of 12 job structures appear to be significant (Warren, 1998).
separate male and female populations, we can find no Whether this analysis needs to be a part of an
compelling reasons to reject the JCQ scales on the expanded JCQ or separate measurements approach,
basis of inconsistency of means and standard such topics should be explored for further compara-
deviations or Cronbach alpha reliability. However, tive analyses.
factor analyses results noted above do raise questions e. New work patterns that involve computer-
about inclusion of certain questions, a potential basis based communication, network communication, and
for future revision of the JCQ scales. mass-media communication serve as the mode of
Although some of the tables in the empirical social coordination in ever larger numbers of social
reliability test (Part II of this article) are based on activities. These may require significantly altered
restricted forms of some scales in order to ensure methodologies for assessing psychosocial work
compatibility with several older databases, the largest experience.
of the new studies now being collected in Europe and f. Quantitative work aspects of work (particu-
Japan include almost complete versions of all of the larly hours of work, spouse work time, income, etc.)
recommended JCQ scales, which further bolsters the certainly need no proof of importance but should be
utility of using the full scales in the future. simultaneously gathered and used along with JCQ
3. Although an integrated review of the JCQ scale's assessments when broad policy implications are to be
shortcomings and future improvement directions is understood.
beyond the scope of this article, some preliminary g. Psychosocial experiences outside of work in
observations about future challenges for the JCQ can the home and community, and across the life span
be made, reflecting both this article and the current (jointly with work experience) must be made a part of
social context of rapidly changing working conditions. psychosocial analytic frameworks even when work-
a. The area of work quality needs to be opened place effects are the primary scientific focus.
up to international political and economic policy h. The creative behavior side of psychosocial
discussions, an important challenge given the accelera- workplace behavior needs to be given further
tion of global economic linkages. JCQ expansions, measurement emphasis, including social interactions
such as the pilot versions of the JCQ global economy which make it possible. To start, more attention
scales, could assist this. Assessment of socially should be paid to existing active job hypotheses to
determined possibilities for control, demand, and facilitate further integration with the active coping
social integration deriving from broad global eco- health and well-being research themes of psychoso-
nomic changes could be assessed. cial research. This extension would also allow new

12. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 333
forms of nonmarket productive output to be better and heart disease in U.S. and Swedish samples but
assessed, and would assist comprehensive dialogue found different retrospectively reported ratings for
about costs and benefits of "the new work organiza- work and family stressors in the two countries (with
tion." "Conducive economic policy" could serve as work being less important in the United States). Kasl
one basis for this expansion (Karasek, 1998; Karasek (1996) speculated that the toll of unemployment and
& Theorell, 1990). the nature of work in general is less important for U.S.
i. Modified assessment methods for psychoso- workers than for European workers. However, this
cial working conditions in less-developed economies has not been tested with direct empirical data on
must also be integrated with existing JCQ scales individual work situations in broadly representative
usage, which has primarily focused on developed populations.
countries. These must assess the relationship between Additionally, there has been much discussion of
psychosocial work costs and benefits and more international differences in work organizational cul-
conventional economic rewards and demographic tures, as when Japanese just-in-time assembly meth-
transformations. ods were introduced into the United States and
Europe (Berggren, 1992). One empirical investiga-
tion of work organization and company policies
PART 1I across seven automobile manufacturers in four
countries shows that "teamwork" is very differently
understood due to national (Japanese, French, Italian,
International Comparison o f the JCQ and German) differences, regional, and company
Scales in Four Countries culture (Frieling, Freiboth, Henniges, & Saager,
1997), although the relative magnitude of intercom-
Rationale
party versus intercountry sources was not assessed.
Trends in working conditions show increased risks Some useful internationally comparative findings
to well-being arising from social and psychological exist for scales very similar to the JCQ. Typical of
characteristics of work in Europe and Japan in these findings are U.S., Swedish, and Japanese studies
reported national statistics (Dhondt, 1994, 1998; which show that the ranking of occupations on
Paoli, 1997; Shimomitzu & Levi, 1992). Available decision latitude scales is very similar in the United
anecdotal reports in the United States in the 1990s States, Japan, and Sweden (see Appendix B).
also suggest growing problems of work-relate.d Unfortunately, the utility of many studies that are
pressures. Comparative assessment of these psychoso- potentially similar is limited by lack of truly
cial exposures between countries in the global comparable scales in each study. In general, absolute
economy could open up the area of "work quality" to scale scores are important for JCQ research because
international political and economic policy discus- they allow comparative analysis of national and
sions. However, significant progress requires interna- occupational differences and facilitate comparative
tional comparisons with standardized instruments--an formulation of some "job strain" definitions. Also,
area in which progress has so far been slight. The although validation studies for the JCQ scales have
international comparisons would also provide an been published for some populations, the cross-
important reference standard for many homogeneous national validity of the JCQ has not been systemati-
population studies. These challenges motivate the cally assessed. Neither has the comparative reliability
present investigation. and validity of the JCQ scales been tested separately
Most international comparative analyses of work for male and female workers. Hall (1994) argued for
focus on economic outcomes. It is well known that the importance of examining women's job character-
there are national differences in the distribution of istics separately. International comparisons of poten-
income, with greater disparities (i.e., higher standard tial gender differences could be useful because female
deviations) occurring in the United States between labor participation patterns vary significantly by
high and low incomes than in Canada, Europe, or COuntry.
Japan. Furthermore, these disparities have increased From a psychometric perspective, the process of
in recent years in the United States. scale validation will often examine scale reliability
Similar differences might be expected for psycho- statistics across multiple populations, with the
social job characteristics. For example, Orth-Gomer presumption that the scale should perform in a similar
(1979) reported similar associations between stress manner across populations. Differences between the

13. 334 KARASEK ET AL.
populations themselves are not the focus. However, Method
from a sociological perspective, the population
differences or similarities are of interest. We will also Populations
follow psychometric tradition and assess the consis-
tency of the scale performance across populations. In The six populations studied come from the United States
the case of job characteristics, the most common (2), Canada-Quebec (2), the Netherlands, and Japan (see
Table 2). The number of participants in each study ranged
sociological hypothesis would be that major national from 580 to 6,053 for a total of 16,601 participants (38%
differences do exist in scale characteristics, because women and 62% men). The participation rates ranged from
the JCQ reflects organizational characteristics of the 65% to 93% (see Table 2). The age boundaries span the full
major social institutional framework of m o d e m adult working life, age 20 to 65 (retirement age), but the
Japanese sample's age span is from age 20 to 60. Part-time
societies--frameworks that have been demonstrated
workers are included if work time is greater than 20 hr/week
to differ between countries from many perspectives. except for the two Canadian samples, which include only
full-time workers (->35 hr/week).
Two populations include the full occupational spectrum--
Objectives managers and professionals, clericals, line workers in white-
and blue-collar occupations, and services workers----based
The main objective of the study is to compare mean on random samples of their geographical location work-
values, reliability, and validity of the JCQ scales forces: (a) the U:S. QES samples from the 1970s (three
separate national samples combined; see Karasek &
across six studies conducted in four different
Theorell, 1990, Appendix 1) and (b) the Quebec province
countries. Complementary objectives are (a) to assess stratified random (Sante-Quebec, 1994) sample from 1990.
the extent of similarities and differences found under Three other samples are broadly inclusive of the full
relatively different national contexts (the United occupational spectrum from manager to line worker: the
States, Quebec-Canada, the Netherlands, and Japan); more recent U.S. New England Medical Center (NEMC)
sample, the Dutch sample, and the Japanese sample. The
(b) to assess potential differences by gender; and (c) U.S. NEMC data include representative samples from all
to compare these differences to published findings status levels in 16 large U.S. workplaces in seven
about scale differences due to occupation. corporations (full samples of 12 middle-sized workplaces
Table 2
Population Definition for the Studies
Participant
Study country Date N % instrument Population type
U.S. QES 1970s 4,319 73 QES/JCQ National random population sample
M = 2841
F = 1478
U.S. NEMC 1994 6,053 71 Base JCQ (modified) a Broadly representative: 16 large
employers, blue and white collar
M = 3676
F = 2377
Canada-Quebec 1990 1,232 77 Full JCQ (minus)b Provincial, stratified random
M = 707 population sample
F = 525
Canada-Quebec-white 1994 2,666 73e Full JCQ (minus)b Regional, 8 companies
collar only M = 1364 65a
F = 1302
Netherlands 1994 1,751 86 Full JCQ Broadly representative: 34 compa-
M = 1228 hies, blue and white collar (limited
F = 523 job mobility/variety)
Japan 1993 580 93 Full JCQ (minus) b 2 companies, blue and white collar
M = 472
F = 108
Note. QES = Quality of Employment Surveys; JCQ = Job Content Questionnaire; NEMC = New England Medical
Center; M = male; F = female.
a Some signlficandy different scales.
b Minus some scales.
¢ Participation for the full population who completed the psychological demands and decision latitude scales.
d Participation for the population who completed also the social support scales.

14. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 335
and random samples of 4 very large workplaces, representa- researcher sent the tabulated data to RK, who constructed
tive of the U.S. workforce in many respects) but omit the final tables.
workers in smaller companies, a lesser fraction of the
workforce. The Dutch sample includes white- and blue-
collar workers from 34 companies, across a range of Analyses
company sizes and industry branches. It deviates from
random selection in that only workers with relatively fixed All analyses were conducted separately for women and
work locations and a limited number of tasks were selected men in the six populations. Mean values and standard
to facilitate physical ergonomic job assessments (however, deviations of each scale were calculated. We used an
this does not exclude professionals such as teachers, nurses, analysis of variance (ANOVA) to evaluate statistical
and some managers). The Japanese sample (Haratani et al., differences between scale means across populations. Given
1997) includes white- and blue-collar workers from two that the samples are large, statistically significant differences
companies with fairly technically sophisticated output between means across populations are expected even for
(telecommunications and power utility). The sixth sample, the small and potentially nonmeaningful differences. Therefore,
second Canadian database from Quebec, is conapesed of only the proportion of variance explained by the study site was
white-collm workers employed in eight white-collar organiza- presented to quantify the magnitude of the variations
tions engaged in semipublic, public, or private service activities. between means. Reliability of the scales was assessed by the
internal consistency as measured by the Cronbach's alpha
coefficients. Concurrent validity was assessed by correla-
Instrument tions between scales and subscales and by correlation of
scales with age a n d education. To assess variability in
correlation coefficients, we computed range and mean
Our intent was to use the full recommended JCQ scales correlations across the six samples. A simple scale was used
(Karasek, 1985). However, some questions were missing in to quantify variability on the basis of the range of correlation
some of the older studies. Therefore, the "lowest common coefficients among the six populations: L = low variability
denominator of questions" was found to maximize compara- (i.e., a difference between the highest and the lowest
tive possibilities. For psychological demands, the five- correlations coefficients < .20); M = moderate variability
question QES version is used, because the full nine-question (i.e., a difference that varies from .20 to .35); and H = high
version was only available in four of the studies (for all variability (i.e., a difference > .35).
correlations, separate tabulations have been made for the full Some factorial validity analyses conducted in these
nine-questions version). For the physical demands scale, populations axe summarized here, but no tables are
although five of the studies had the one-question version, presented because of space limitations. The exact methodolo-
only the relatively recent Dutch sample had the full gies of these analyses are not always consistent across
recommended five-question scale, and thus, most tabula- populations. Separate factor analyses of decision latitude
tions are based on the one-question version. Only the and psychological demands; then decision latitude, psycho-
Canadian sample had the five-question social support scale, logical demands, and social support; and finally, all scales
but all of the other samples had a QES-based four-question together have been reported. Sometimes the two decision
version, which is used in the tables. No study had the full latitude subscales and the psychological demand scale have
six-question job insecurity scale, thus a special two-question been tested as two factors, sometimes as three. All analyses
version of the scale, available in three studies (U.S. QES; were conducted using standard statistical analysis programs
U.S. NEMC; and the Netherlands), was computed only for (Study 1, 5, 6; SAS Institute, 1990; and Study 2, 3, 4; Stata
this article. The original English version of the JCQ was Statistical Software, 1997).
used, or validated tramlafions in French (Brisson, Dion, et al.;
Brisson, Larocque, et al., 1998; Larocque, Brisson, & Blanchet,
in press), in Dutch (Houtman, 1995; Reuvers et al., 1998), and in Comparison of Between-Occupation Variance
Japanese (Kawakami & Fujigaki, 1996; Kawakawi et al., and Occupational Rankings
1995).
Although consistent coding of occupations across all the
databases was not possible for this article, the use of
Data Collection interoccupation differences in job characteristics present an
important reference standard for assessing the relative
The instrument was self-administered in most studies importance of intercountry differences. Thus, the results for
(Study 1, 2, 4, 5, 6) or administered during a face-to-face the one study database that does have an interoecupation
interview (Study 3). Self-administration was usually done at ANOVA (U.S. QES) are included here, and an occupational
the workplace. Workers were allowed by their employers to ANOVA for scales similar to the JCQ in Sweden is also
fill in the questionnaire during regular working hours. presented (Swedish scales from Johnson and Stewart, 1993;
Although data on all samples had previously been collected, U.S. scales from the U.S. QES study in this article; Schwartz
tabulated, and in some eases published by participating et al., 1988). The Swedish analysis is based on a similar
researchers, this previous material did not always follow scale for decision latitude; however, the support scale in
exact JCQ guidelines or was not presented in a comparable Sweden is only a "possibility-of" assessment (mainly
manner. Therefore, for the parpose of the present article, one instrumental) and only for coworkers. Also, the Swedish
of us (RK) requested participating researchers to retabulate psychological demand scale is assessed more subjectively
data following defined JCQ guidelines (as modified above) and has fewer questions than the U.S. scales. The
to allow meaningful comparisons. Each participating between-occupation variance reported is a percentage of the

15. 336 KARASEK ET AL.
Cronbach alpha reliable scale variance (this represents For psychological demands (five items), the U.S.
between .60 and .75 of the total variance for the Swedish NEMC women's population is higher than others, but
scales). An additional person-based demographic contribu-
tion to psychosocial scales between occupation is also otherwise there are no major deviations for men or
reported in both U.S. and Swedish studies. This addition women on this scale. The physical demands scale
increases the variance somewhat, of course, not because of does not show consistently higher levels for men than
the job alone, but because of the interaction of person and for women. It shows a substantially lower level in the
job (e.g., the additional effect of age on the decision
anthority of managers). This effect is roughly corrected for U.S. NEMC sample than in the U.S. QES sample. The
in the Swedish sample by assuming the same average job insecurity scale (based on the specially calculated
contributions from demographics in Sweden as in the United comparable subscale across populations) shows a
States, averaged across scales. substantially higher level in the 1990s in the United
The rankings of occupations on the JCQ decision latitude
scale are compared for the seven occupations reported in States than it did in the 1970s.
Kawakami et al.'s (1995) two-company study, compared One highly consistent finding observed in all
with the JCQ scale rankings of the same occupations in the studies is the gender differences in skill discretion and
U.S. and Swedish nationally random samples, The U.S. and
decision authority. Indeed, women have consistently
Japanese studies use the JCQ scales reported in this study,
whereas a similar, non-JCQ scale is used in Sweden lower scale means for both these subscales. These
(Johnson, Stewart, Friediund, Hall, & Theorell, 1990). gender differences tend to be smaller in the Quebec
stratified random population sample than in the other
samples. The gender differences average about a
Results quarter of the population's standard deviation.
The scale standard deviations are generally higher,
Means and Standard Deviations of JCQ Scales as would be expected in the first three populations,
which have broadly representative samples, than in
The means are very similar across studies (see others in which restrictions of populations do occur,
Table 3). Although the difference between means are for both men and women. In three representative
statistically significant among the studies for all samples, the standard deviations are very similar on
scales, the proportions of the variance of scale scores all scales.
explained by study site are small, that is, generally
less than 5% for men and women for the more reliable
scales. Within men samples, the proportions ex-
Internal Consistency of JCQ Scales
plained ranged from 1% to 4% for decision latitude,
psychological demands, supervisor support, and Internal consistency of the scales tend to be similar
coworker support (averaging 2.5%). These propor-
across populations and between men and women (see
tions were, respectively, 6% and 9% for physical
Table 4). The Cronbach's alpha coefficients are
demands and job insecurity, where only three studies
generally acceptable (overall average alpha for
have data and there are reliability limitations for the
women is .73 and for men is .74). The highest and
scale forms included in the study. Within women
most acceptable values of the coefficients are found
samples, the proportions explained ranged from 3%
for the decision latitude, physical demands, supervi-
to 10% for decision latitude, psychological demands,
sor support, and coworker support scales. However,
job insecurity, supervisor support, and coworker
the psychological demands scale, with five questions,
support (averaging 4.8%), whereas it was much
is only borderline (Nunnaly & Bernstein, 1994).
greater (17%) for the single-question physical de-
mand scale. Some minor deviations occur for the skill discretion
Although differences between samples are gener- scale, which falls to borderline levels in the Dutch
ally small, some specific tendencies can be observed. study for men and women and for the decision
The decision latitude means are the highest in the two authority scale for men. However, taken as a single
Quebec samples for both men and women. The scale, the decision latitude scale has quite acceptable
decision latitude means and more specifically the coefficients. The skill discretion scale has a low
decision authority means are lower in the U.S. QES reliability for Japanese men but is acceptable for
(1970s) sample than in the U.S. NEMC (1994) Japanese women. Decision latitude has good reliabil-
sample for both men and women. The decision ity in Japanese women but remains low for men. The
latitude means are the lowest in Japan and U.S. QES job insecurity scale also has low coefficients in two
(1970) in both men and women, although for women, out of the three populations for which data are
the Netherlands sample is as low as Japan's. available.

16. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 337
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0
z
~~11~
II "
~v
~ ~ ~.~
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c~
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~~ ~ ' ~

17. 338 KARASEK ET AL.
Table 4
Cronbach 's Alpha Reliability Coefficients of the Job Content Questionnaire Scales
Among Men and Women in Six Samples
Study sample
U.S. U,S. Canada- Canada-
Scale QES NEMC Quebec Quebec-W Netherlands Japan M
Men
Skill discretion .75 .79 .79 .80 .67 .59 .732
Decision authority .69 .70 .71 .70 .61 .66 .678
Decision latitude .83 .84 .86 .86 .77 .68 .807
Psychological demands (9 items) -- -- .68 .75 .74 .72 .723
Psychological demands (5 items) .63 .71 .59 .67 .57 .61 .630
Physical demands NA NA -- -- .86b -- .860
Job insecurity .60a .74 -- -- .49 -- .610
Supervisor support .85 .80 -- .82 .83 .89 .838
Coworker support .80 .72 -- .72 .78 .74 .752
Women
Skill discretion .71 .75 .78 .79 .65 .80 .747
Decision authority .72 .64 .70 .63 .70 .68 .678
Decision latitude .80 .81 .85 .84 .77 .84 .818
Psychological demands (9 items) -- -- .72 .72 .69 .72 .713
Psychological demands (5 items) .62 .72 .63 .64 .51 .65 .628
Physical demands NA NA -- -- .79b -- .790
Job insecurity .47c .76 -- -- .52 -- .583
Supervisor support .83 .84 -- .83 .83 .87 .840
Coworker support .81 .75 -- .69 .82 .76 .766
Note. QES = Quality of Employment Surveys; NEMC = New England Medical Center; Quebec-W = white-collar only.
Dashes indicate no data available.
a 0.53 for the three-item scale of job insecurity, b For the five-item scale of physical demands, c 0.41 for the three-item
scale of job insecurity.
Correlations Between JCQ Scales and coworker support scales, two subcomponents of
and Subscales the social support scale, are correlated at .40.
Generally, there is little difference in the decision
The correlations between JCQ scales and subscales latitude scale's two subcomponents, skill discretion
represent 26 possible correlations (decision latitude and decision authority, in correlations with the other
correlations with its subscales are excluded). When scales. One exception is the Japanese men for whom
analyzed separately for women and for men, these the skill discretion coefficients are three times as large
produce a matrix of 52 possible correlations (see as the decision authority coefficients for both
Table 5). Across study populations, 33 correlations supervisor and coworker support. The decision
show low variability, 12 show moderate variability, latitude scale correlates strongly (given moderate
and 7 show high variability. In a number of cases, the scale reliability) with the two social support subcom-
variability occurs from extreme values observed in ponents; it correlates moderately with psychological
the Japanese population (some of the idiosyncratic demands and negatively with physical work and job
Japanese findings may be due to the very small insecurity.
women's sample; see below). If we exclude these The psychological demand scale displays a low and
extreme values, 39 correlations (75%) have low very variable positive correlation with decision
variability across populations. latitude for both men and women (all the high-
Review of specific associations reveals the struc- variability associations are from the psychological
ture of the JCQ scale relations. Decision latitude is the demand scale). However, in the above studies, only
additive combination of skill discretion and decision the U.S. women's sample of the 1970s and the Dutch
authority scales, which are consistently correlated at sample shows the negative correlation, which is
about .55 for both men and women. The supervisor associated with an increased prevalence of the "job

18. SPECIAL SECTION: JOB CONTENT QUESTIONNAIRE 339
strain" combination. The correlation is actually age correlations with any scale. Education has strong
strongly positive in the small sample of Japanese negative correlations with decision latitude and
women. Correlations of psychological demands with physical demands, but low correlations otherwise.
decision latitude are somewhat higher for men than There is a moderately strong and consistent negative
for women. The findings for the nine-questionversion association between age and education (about -.20)
of the psychological demand scale show similar in all of the samples (which is much stronger for the
variability. Japanese women). These correlations may reflect
The psychological demands scale varies across intergenerational differences in education levels
populations in its correlation with physical demands. (lower levels for older generation workers) and the
It is strongly positive in two out of three populations broad age range (20 to 65 years) of included
where it is available, but very low in the third one (the participants.
U.S. NEMC sample). Psychological demands has The Japanese sample has substantially different
major associational variability with supervisor sup- correlations of decision latitude scale with age and
port: In the U.S. QES it is strongly negatively education than the other populations. There is no
correlated, in Japan it is uncorrelated, and in other association between education and either skill discre-
populations it has a low correlation. Physical tion or decision authority for the Japanese men and
demands show a consistent negative association with negative correlations for the Japanese women, but a
decision latitude, and correlations are stronger for strong positive association exists in all other samples.
men than for women. Job insecurity shows generally For the Japanese women, a high positive association
consistent associations with other scales, particularly between age and psychological demands is also
a moderately strong negative correlation with the observed. Additionally, they have a high positive
decision latitude, supervisor, and coworker support correlation between age and skill discretion and a
scales. weaker negative correlation between education and
Correlations between the nine-item version of the skill discretion (although this correlation reduces to
psychological demands scale and other JCQ scales zero when age is adjusted; Kawakami et al., 1995).
are shown in Table 6. The correlation between the Correlations of supervisor support and decision
five-item and the nine-item versions is high (.88). The latitude with education are also very small for the
variability of associations with other scales remains Japanese sample but are strongly positive for the
with the nine-item version (among the four popula- other samples.
tions for which it is available). The nine-item version Several consistent gender-related exceptions are
has a more positive overall correlation with decision observed. Demands are in general more consistently
latitude. related to decision latitude for men than for women:
The physical demands scale displays a low and Physical demands are more highly negatively corre-
variable positive correlation with job insecurity for lated with decision latitude and education for men,
both men and women and a low and negative and psychological demand associations with decision
correlation with supervisor and coworker support, latitude are somewhat higher for men than for
except for the U.S. QES women's sample and the women. Physical demands are more highly negatively
Japanese women's sample. correlated with education for men than for women,
and psychological demands are negatively correlated
with age for men, except for the Dutch sample, but
Correlations of JCQ Scales With weaker for women, except for the Japanese sample
Age and Education and for one Canadian sample, in which correlations
for men and women are nearly the same.
Correlations of JCQ scales with age and education
represent 32 possible correlations (see Table 7). Of
these, 16 display low variability across populations, Factorial Validity of JCQ Scales
10 show moderate variability,and 6 show high variability.
Here particularly, extreme values are observed in the The U.S. population from the 1970s shows a clear
Japanese sample. After excluding them, 26 correla- factor pattern corresponding to the JCQ scales for
tions (81%) have low variability across populations. men (which is not surprising because this was the
The correlations with age and education are, in JCQ defining base sample) and also for women. Also
general, lower than those observed between the JCQ in the United States, the NEMC sample from the early
scales and subscales themselves. There are no strong 1990s shows a confirming pattern for most factors for

19. 340 KARASEK ET AL.
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