The unpredictable biological variability is also associated with the number of possible biological responses to demands in the environment. The larger the number of biological cycles, the larger the number of “ways out” from difficult situations. Perhaps this biological principle is also applicable in psychosocial processes.

PSYCHOLOGICAL FLEXIBILITY

Biological chaos theory has its counterpart in psychological coping theory. One way of summarizing this is to say that individuals who report that they have many different ways of responding to demands—coping strategies—at their disposal will do better in demanding situations. Shalit (1978) developed his “coping wheel” in order to predict which young men and women would be more able than others to stand the horrors of the Arab–Israeli wars during the 1960s and 1970s. His ideas were simple and straightforward. Those who report that they have many interests and areas of activity in life would do better than others. Furthermore, those who feel that they are in control of and have positive feelings about most of these activities—particularly those that are rated to have high priority—would be more likely to do better than others. According to these ideas, Shalit constructed a measurement technique that consists of a wheel with twelve segments. The subjects are asked to describe what activities they have in life. They only use one or two of their own words to describe the activity and they may use as many segments as they please. Afterwards they are asked to order the activities with regard to magnitude of importance (if they feel they are able to), and to rate them with regard to emotional feelings that they are associated with (from negative through neutral to positive) and with regard to the degree to which they feel they are in control. A recent study from our group has shown, for instance, that a programme for mental stimulation by means of pictures of pieces of art and discussion about the thoughts that these pictures evoke (exercises that take place for an hour once a week during four months) can increase the number of coping strategies and improve the pattern of coping in old people (Wikstr¨om et al., 1994). The effects of this programme were compared to the effects of ordinary conversations of the same frequency and amount. Improved emotional state and health were observed along with the improved coping patterns in the experimental group, but not in the control group.

In parallel with the observations on coping patterns in general, it might be speculated that flexible coping patterns could protect workers from poor health, and also that a work situation that enforces the development of such coping patterns stimulates the development of health in the workplace.

Another way of categorizing coping patterns is to group them into open and covert strategies. In a series of studies we have used a Swedish short version of a questionnaire measuring coping patterns (Harburg et al., 1973; Knox et al., 1985; Theorell et al., 1993). The person is asked what he or she would typically do if exposed to unfair treatment by the boss. Parallel questions are made about unfair treatment from a workmate. A number of fixed response categories are used, and the degree to which the person uses different strategies is rated on a four-graded scale. Factor analyses have shown that the responses can be grouped into open (“I would say immediately what I think” etc.) and covert (“I would not do anything”, “I would brood about it at home” etc.) patterns. Covert coping is associated with sleep disturbance in both men and women (Theorell et al., 1993). In a more recent study of 6000 employed women and men, however, a low decision latitude was statistically significantly related to a less open and a more covert coping pattern in both men and women although the relationship was stronger in women than in men (Theorell et al., 2000). In this later study we also found that covert coping pattern—at least in men—was associated with high blood pressure. This may indicate that there is a psychophysiological cost (long lasting energy mobilization) in covert coping.

The meaning and social context of flexibility may be markedly different for different groups. For instance, there are marked gender differences in the way in which psychosocial work organization correlates with individual coping patterns. Both intellectual discretion and authority over decisions increase significantly with age in men but not in women. This is consistent with findings in other countries. There are strong inverse correlations between social support, on the one hand, and psychological demands and the less covert coping, on the other, for women: the more support, the fewer demands and covert coping. In men, on the other hand, no relationship is found between covert coping and social support, whereas a weaker inverse relationship is found between social support and psychological demands. Social support at work stands out as a more significant buffer against stressful experiences for women than it does for men in this study.

But how do we stimulate flexible coping patterns in the work environment? In the following section I use Karasek’s demand–control model (Karasek, 1979) to clarify my points.

ORGANIZATIONAL FLEXIBILITY

The organization—for example, of a workplace—can be regarded in the same way as that of a human being. According to most of the management literature, flexibility is an important ingredient in prosperous organizations (Anderson&King, 1993). There may, unfortunately, be a conflict between organizational flexibility and the individual’s flexibility. This is one of the important themes in this review. Flexibility from the Individual’s Point of View in Relation to Health Risk

One of the most widely applied theoretical models for studyingwork organization in relation to individual health risks is the demand–control model. When Karasek introduced this model, it was an architect’s synthesis of the stress research/psychology and the sociology research traditions (Karasek, 1979). Generating the concept “lack of control”, or “lack of decision latitude”, as Karasek labelled it, goes back to the old sociologists’ question: “is the worker alienated from the work process?”. It was assumed that the possibility to utilize and develop skills (skill utilization), a concept developed in work psychology, was closely related to authority over decisions. In factor analysis of responses to questions about work content these two factors are mostly positively related, and, accordingly, they have been summated to constitute decision latitude (Karasek & Theorell, 1990). The other dimension, psychological demands, included qualitative as well as quantitative demands.

It should be emphasized that the demand–control model was never intended to explain all work environment related illness. Thus, there was no element of individual variation introduced into its original construction. On the contrary, the model dealt with the way in which work is organized, and the way in which this relates to illness. This simplicity has made the model useful in organizational work. A model that tries to explain “all of the variance” would have to be more complicated and would be scientifically more, but educationally less, successful than the simple model that was introduced.

According to the model, there is interaction between high psychological demands and low decision latitude. If demands are regarded as the x-axis, and decision latitude as the y-axis in a two-dimensional system and the different combinations of high–low demands and high– low decisions are regarded, four combinations are recognized. The high demand/low decision latitude combination is regarded as the most relevant to illness development. Karasek uses a drastic analogy to describe this combination: if a person is crossing a street and he sees a truck approaching he may speculate that he will be able to cross the street without being hit by the truck—if he regulates his speed appropriately. However, if his foot gets stuck in the street his decision latitude diminishes dramatically and he is now in an extremely stressful situation. According to the theory, this kind of situation (not necessarily so dramatic), if prolonged and repeated for a long time, increases sympathoadrenal arousal and at the same time decreases anabolism, the body’s ability to restore and repair tissues. The combination of high psychological demands and high decision latitude is defined as the active situation. In this situation the worker has more possibility to cope with high psychological demands because he or she can choose to plan working hours according to his or her own biological rhythm, and also has good possibilities for developing good coping strategies, facilitating feelings of mastery and control in unforeseen situations. The low demand/high decision latitude situation (relaxed) is theoretically associated with the smallest illness risks for the majority of subjects, whereas the low demand/low decision latitude situation, which is labelled “passive”, may be associated to some extent with the development of psychological atrophy: skills that the worker had when he was employed may be lost (Karasek&Theorell, 1990).

The most important component in Karasek’s demand–control model is perhaps decision latitude, since it is directly translatable into work redesign. Using our reasoning above regarding coping strategies, it can be stated that the two components of decision latitude FLEXIBILITY AT WORK IN RELATION TO EMPLOYEE HEALTH 163 both have major importance for the development of flexible coping strategies. A work site with a high degree of intellectual discretion will stimulate the development of such strategies in the employees and a high degree of authority over decisions will allow this to occur.

There have been two recent developments aimed at introducing social support to the demand–control model.

Iso-Strain

Firstly, Johnson has included social support in the theoretical model. A study of cardiovascular disease prevalence in a large random sample of Swedish men and women indicated that the joint action of high demands and lack of control (decision latitude) is of particular importance to blue-collar men, whereas the joint action of lack of control and lack of support is more important for women and white-collar men (Johnson&Hall, 1988). The multiplicative interaction between all the three aspects (iso-strain; demands × lack of control × lack of support) was tested in a nine-year prospective study of 7000 randomly selected Swedish working men. Interestingly, for the most favoured 20% of men (low demands, good suport, good decision latitude) the progression of cardiovascular mortality with increasing age was slow, and equally so in the three social classes. In blue-collar workers, however, the age progression was much steeper in the worst iso-strain group than it was in the corresponding iso-strain group in white-collar workers (Johnson et al., 1989).

Working Life Career

Secondly, attempts are now being made to use the occupational classification systems in order to describe the “psychosocial work career”. Researchers have pointed out that an estimate of work conditions at only one point in time may provide a very imprecise estimation of the total exposure to adverse conditions (House et al., 1986). Therefore, in order to explore the effects of the total working career, a large group of randomly selected working men and women in Sweden were interviewed about occupations that they had had throughout their whole career. For each year the job description was translated to the Nordic classification of occupations. Occupational scores were subsequently used for a calculation of the “total lifetime exposure”. These scores had been derived from the average scores (demands, control and support) calculated separately for a number of subgroups within each occupation. Thus, they were calculated separately for men and women, for those below and above 45 years of age, and for those with less than 5 years of employment, between 5 and 20 years and finally above 20 years of employment. The “total job control exposure” in relation to nine-year age-adjusted cardiovascular mortality in working Swedes was studied. It was observed for both men and women that the cardiovascular mortality differences between the lowest and highest quartiles were two-fold, even after adjustment for age, smoking habits and physical exercise. Furthermore, if the individual had had several large fluctuations in job control over the years, the risk of cardiovascular death during follow-up increased even more, up to almost three-fold compared to the high control group (Johnson et al., 1993). The index of psychological demands recorded in this study did not predict risk of cardiovascular death in theway thatwas expected. (The index consisted of two questions: “Is your work hectic?” and “Is your work psychologically demanding?”). For men it had no predictive value at all, and for women it predicted significantly in the reversed direction: the higher the psychological demands during the career, the lower the risk. These latter findings may indicate either that the index is not capturing psychological demands or that demands are associated with risk in different ways in the short term (according to previous studies) compared to the long term. They also illustrate differences between men and women in the patterns of correlations between psychosocial factors and cardiovascular disease risk (Hall, 1990).

A recent study has shown that the level of control inferred from the job title—after taking age, gender and time of exposure to the occupation into account—has a different development inworking men who have developed a first myocardial infarction during the 10 preceding years than in a control group of age matchedmenwithout this experience (Theorell et al., 1998). The 25% of the employed men who had had the least favourable development with regard to decision latitude during the preceding ten years had a significantly elevated risk of developing a myocardial infarction. This was particularly true in the 45–54-year-old men, among whom the excess risk was 80% after adjustment for accepted biomedical risk factors and social class. This observation may illustrate that the timing of a first myocardial infarction in a working man may be related to falls in control level at work. In the near future there will be increasing numbers of lay-offs and changes in jobs. Due to the increasing pressures in the labour markets, individuals will have to accept jobs with much lower levels of decision latitude than they have been accustomed to. Thus, it is to be expected that the number of myocardial infarctions will show a further increase.