Introduction
The presence of systematic differences in health between socioeconomic groups as measured by income, occupation and education is well documented [
1,
2]. The health gradient is not restricted to low-income countries, but is also present in countries with well-established welfare systems [
3]. Compared with higher socioeconomic groups, the lower socioeconomic groups have a higher prevalence of poor self-reported health (subjective health complaints, self-rated general health, chronic pain, and disability), higher incidence of specific diseases, and higher rates of mortality [
4].
Subjective health complaints (SHC) are often characterized by few if any objective findings [
5], and there is a high prevalence of these complaints in the general population [
6,
7]. SHC are also the main reasons for long-term sick leave and disability in Norway [
8‐
10] and other western countries [
11]. Self-rated general health is a well-validated and commonly used health indicator, and it is a strong predictor of future mortality and use of health services [
12‐
15]. Individuals in lower socioeconomic groups report poorer self-rated health and more subjective health complaints compared to those in the higher socioeconomic groups [
4,
16‐
19].
However, we still do not know all the mechanisms that might explain the association between socioeconomic status (SES) and health [
20]. Occupational factors are important predictors for employees’ health [
21] and it has been suggested that physical and psychosocial demands and conditions at work may constitute important links between SES and health [
19,
22‐
25]. Physical working conditions (e.g., physical strains in doing the job, monotony at work) have been shown to explain most of the social gradient in self-rated health among a representative sample of Swiss employees [
23]. Similarly, in a cohort from Finland, heavy physical working conditions explained a large part of the socioeconomic inequalities in self-rated health [
22]. However, the importance of control [
22] and the relationship between effort and rewards [
25,
26] have also been shown, although coping has been reported to be more important to health than control [
27]. Coping are defined and measured in many different ways. The “ways of coping” model, which focuses on coping strategies, is one of the most influential models [
28]. However, according to Ursin and Eriksen [
29], the strategy chosen does not predict the internal state and thus it does not predict health. In their Cognitive Activation Theory of Stress (CATS) they argue that coping predicts relations to health and disease only when it is defined as positive response outcome expectancy.
The Cognitive Activation Theory of Stress [
29] can be used to explain the association between coping and health, and the importance of coping for socioeconomic differences in health. Whenever an individual is faced with threats, challenges, or demands, an increase in arousal or activation will follow. If a person has established positive response outcome expectancies (The CATS definition of coping), this increase in activation is short and has a positive influence on health. If the individual expects that he or she will not cope with the situation or the demands, the activation may be sustained over time, which is associated with illness, disease and possible poor health. In CATS, response outcome expectancies may be positive (
coping), negative (
hopelessness), or the individual may have established no (
helplessness) response outcome expectancy. There is no linear relationship between the challenges or demands the individual is faced with, and the increase in arousal. It is the individual’s experience of the demands and the expectancies of the response outcome that is important for the sustained activation and the possible negative health effects [
29]. Coping is shown to be an important predictor for socioeconomic differences in health [
16,
30,
31]. Lower scores on the expectancy to cope are demonstrated among individuals with low socioeconomic status, both within and between countries [
32]. High level of coping is associated with high social position and social success, in both humans and animals [
33]. A large Swedish study, SLOSH [
16], has used a newly developed scale to measure expectancies of coping as defined in CATS. In this study, coping was a better predictor for health than socioeconomic status, and the relationship between coping and SES was almost linear. These results might have important practical implications, as it is possible to alter individual’s response outcome expectancies. If coping is a link between SES and health, increasing the individuals’ expectancies of coping might help to reduce the social gradient in health. Individual differences in the expectancy and ability to cope with the demands faced in life in general and, more specifically, at the workplace, may also be important for how the work characteristics affect the employees [
27,
34]. Employees with lower income report lower levels of coping and more obstacles in life [
35]. However, coping seems to dampen the negative effects of low income. When individuals with low income report a high level of coping, their health and wellbeing is comparable with the higher income groups. Thus, high levels of coping might make it more likely for employees to manage the consequences of an adverse work environment. Previous studies have also found coping to be an important predictor for subjective health complaints [
27,
34,
36,
37], and for self-rated general health [
16,
38].
In the present study, education will be used as a measure of socioeconomic status. Education is a well-established measure of socioeconomic status in Norway. There are relatively small differences in income in different occupational status in this country, and education is more comparable across different countries than occupational status and income [
39]. Although schooling is an integral part of society in Norway, research has shown that there is a linear relationship between higher education and better health [
3].
The aim of this study is to explore the contribution of socioeconomic status, physical workload, and response outcome expectancies in explaining subjective health complaints and general health. It is assumed that socioeconomic status, physical workload, and response outcome expectancies are associated with health. We hypothesize that response outcome expectancies will be a stronger predictor for SHC and self-rated health than education and physical workload. Furthermore, we hypothesize that response outcome expectancies will mediate the effect of education on SHC and self-rated health, and that response outcome expectancies will mediate the effect of physical workload on SHC and self-rated health.
Women generally report more subjective health complaints than men [
40], and there might be different mechanisms that affect health and health complaints in men and women. Therefore, we will explore the hypotheses across gender.
Discussion
The central purpose of this study was to investigate whether response outcome expectancies are a stronger predictor for SHC and self-rated health than education and physical workload, and if response outcome expectancies mediate the effects of socioeconomic status and physical workload on SHC and self-rated health. The results confirmed the first hypothesis of the paper, as response outcome expectancies were a stronger predictor than education and perceived physical workload for subjective health complaints and self-rated general health. This result is similar to a study from Sweden, which used the same scale to measure response outcome expectancies as the current study [
16]. Coping was a stronger predictor for self-rated health than both subjective and objective social status in the Swedish study [
16]. The authors concluded that coping was one of the mechanisms underlying the association between socioeconomic status and health. The present study partially supports the hypothesis that coping, or in this case helplessness/hopelessness, might function as a mechanism between socioeconomic status and health, as helplessness/hopelessness fully mediated the effect of education on self-rated health and SHC for the female group. However, the effect of education was small, and for men it had no significant effect on SHC, and only a direct effect on self-rated health. Ihlebæk et al. [
7] also found that education was a significant predictor for SHC in women, but not in men. Furthermore, in line with the present study, Ihlebæk et al. [
7] found that physical workload was significantly related to SHC for both genders. However, the full model in that study, with several predictors such as lifestyle, work-related factors, etc., explained little of the variance in SHC. The authors suggested that coping and other psychological factors might be of stronger importance for SHC [
7].
In the present study, helplessness/hopelessness was a stronger predictor for SHC and self-rated health than education and physical workload. Furthermore, helplessness/hopelessness seemed to be a mechanism between physical workload and health, as it partially mediated the effect of physical workload on SHC and self-rated health for women, and fully mediated the effect of physical workload on SHC for men. This is in accordance with a previous study that found unfavorable coping strategies to be related to negative work characteristics and poor health [
46]. The results of the present study are also in line with a study by Karademas et al. [
47], where helplessness had both a direct effect on subjective health, and an indirect effect through certain coping strategies. In the present study, the association between physical workload and the health outcomes were stronger in the female group than in the male group. The results are in accordance with a study of anesthesiology students, were female students more often reported higher concentration demands and limited possibilities to control work compared to male students [
48]. The present study indicates that the effect of physical workload on SHC is partially due to individual’s lack of coping, especially in men.
The results may be explained within the framework of CATS [
29], where the individual’s expectancy of being able to cope with the demands and challenges he or she encounters in the workplace are more important for the employees’ health than the demands or objective work characteristics themselves. However, the subjective perception of physical workload does not necessarily correspond with the actual physical workload. Research has shown that correlations between subjective perceptions of work conditions and the actual objective work conditions tend to be weak [
49,
50]. Christie and Barling [
30] suggest that coping and the work environment are dynamic and responsive to each other. In their longitudinal study, individuals who reported lower levels of coping at baseline increasingly perceived more work stressors and health problems over time. The same pattern yielded for individuals who reported more work stressors at baseline, as these perceived less degree of coping over time than those who initially reported less work stressors. In line with the present study, these findings make it reasonable to assume that poor health might partly be a product of individual’s expectancies of coping with difficulties.
The main strength of the present study is that it is based on a large and representative sample of Norwegian municipality employees, which provides a good basis for generalization of the results to other worksites. The sample is diverse with regard to work type and workplace size, which reduces the possibility of effects of localization or group specific effects. However, a response rate of about 50 % may limit the validity of the findings. Even though considerable efforts were made to improve the response rate by providing information to the employees about the project, it remained low. The high predominance of women in the sample (about 80 %) represents characteristics of the population in general, as 69 % of all public sector employees are women, with the majority working in the municipalities [
51]. In the two participating municipalities, 79 % and 68 % of the employees are women. However, caution should be made when generalizing to private sector employees.
The majority of the participants in this study had higher university education, and the sample was generally highly educated. Thus, the significance of education on health and the relationship between education and helplessness/hopelessness might have been undermined due to small variance. Further studies should investigate the relationship between the variables in a more heterogeneous sample. In addition, the inclusion of more items and preferably validated scales of workload and work characteristics would provide more reliable conclusions regarding the relationship between work characteristics, coping, socioeconomic status, and health.
Although several of the results in the paper were statistically significant, the coefficients and effect sizes were relatively small. This may be a consequence of the large sample size of the study, as large samples make it more likely to achieve statistical significance even with small effect sizes [
52]. However, a large sample increases the likelihood that the results are in accordance with the actual population value [
52], and even small effect sizes might have important practical significance. For example, as it is possible to influence and alter individuals’ response outcome expectancies, coping has important implications for interventions. Thus, for jobs where it is difficult to remove the objective work stressors, interventions should focus on improving the employees’ expectancies of coping. Empowerment interventions aimed at strengthening employees’ positive response outcome expectancies may enable the employees to manage the possible consequences of facing a tough work environment, and thereby improve the employees’ health and reduce health inequalities in the population. According to Rappaport [
53], empowerment involves both a subjective perception of personal control, and a sufficient degree of real social impact. Thus, interventions should focus both on strengthening the employees’ positive response outcome expectancies (individual level), and to facilitate and create opportunities to cope (organizational level). At the individual level, Cognitive Behavioral Therapy (CBT) can be used to increase employees’ positive response outcome expectancies. The aim of CBT at an individual level is to challenge and change individuals’ unhelpful thought patterns in a positive direction by focusing on his or hers previous coping experiences, and gaining new coping experiences through behavioral experiments. In line with CATS, the treatment is based on the belief that coping generalizes, and the goal is for low-coping individuals to obtain expectancies of coping. Examples of such empowerment interventions at the organizational level are individual adjustment of tasks and goals, giving the employees opportunities to participate in goal setting, manageable sub-goals, social support from supervisors and co-workers, and acknowledgement and feedback concerning the employees work achievements.