Johansson JA (1,2), Rubenowitz S (1,2), Hansevi P (1), Lindgren P (1). (1) Lindholmen Development, Goteborg, Sweden; (2) Goteborg University, Dept. of Psychology, Goteborg, Sweden.
Aim: A cross-sectional study was carried out as a basis for a cohort study. The cross-sectional study was also conducted to examine the relationships between i.a. psychosocial factors at work and work-related musculoskeletal symptoms (WMSSs).
Method: A total of 220 elder-care and child-care workers participated in the cross-sectional study. The study was carried out at working hours. A questionnaire was used to gather information on the psychosocial work and environment and WMSSs. The psychosocial factors included in this study were Decision Latitude (8 items, Cronbach alpha=0.81) and Psychological Load (4 items, Cronbach alpha=0.78). Each factor was trichotomized into a low, a moderate, and a high category. The WMSSs measures included neck, shoulder and low-back symptoms during the past 12 months. The prevalence rate (P) on WMSSs was analyzed according to Karasek’s 2-dimensional model. Prevalence Odds Ratio (OR) with 95% confidence intervals (CI) were calculated and the subjects were stratified by age according to Mantel-Haenszel weighted OR.
Results: The 12 months prevalence rate (P) were: P=0.56 (CI:0.53-0.58) for neck symptoms, P=0.60 (CI:0.58-0.62) for shoulder symptoms, and P=0.63 (CI:0.61-0.65) for low back symptoms. The theoretically highest strain group (i.e. a high psychological load combined with a low score on decision latitude) also shows the highest prevalence OR of WMSSs in this study. In the high strain group, the age-adjusted prevalence OR was 4.03 (CI:2.92-5.59) for neck symptoms, 4.28 (CI:3.08-5.97) for shoulder symptoms, and 2.75 (CI:1.99-3.80) for low back symptoms.
Conclusions: The study supported the hypotheses that psychological work factors are related to WMSSs. The 2-dimensional model makes it likely to identify groups of workers who are at high risk for WMSSs. These findings should be observed with interest in the context of prevention WMSSs among elder-care workers and child-care workers.
Kawakami N (1), Haratani T (2), Shimizu H (1). (1) Department of Public Health, Gifu University School of Medicine, Gifu, Japan; (2) National Institute of Industrial Health, Ministry of Labour, Kawasaki, Japan.
Aim: The study aimed to know the relationships of individual, work group-based and job title-based assessments of job strain with coronary heart disease (CHD) risk factors.
Method: A survey was conducted for all employees of an electrical factory in Japan using a questionnaire concerning work stress and other covariates in 1984 (response rate, 92%). Systolic and diastolic blood pressures and serum total cholesterol were measured at the same time. The study focused on 94 blue-collar work groups, each of which included at least 10 male respondents. A total of 36 job titles were considered, each of which included at least 5 male respondents. Individual scores (0 or 1) of three job stressors, i.e., job overload, low workpace control and low worksite support, were determined based on the questionnaire. Work group-based scores of these job stressors were defined as mean of individual job stress scores by work groups. Job title-based scores of these job stressors were similarly defined as mean of individual scores by the job title categories. The analysis was conducted for hypertension or cardiovascular disease. Multiple linear regression analysis was conducted to know the effects of the job stressors on serum total cholesterol, systolic and diastolic blood pressures, controlling for age, obesity and alcohol drinking, using the individual, work group-based or job title-based scores.
Results: Interaction between individual scores of job overload and low workpace control was marginally associated with higher diastolic blood pressure (p=0.06). Work group-based scores of low workpace control significantly and positively correlated with serum total cholesterol (p<0.05). Interaction between work group-based scores of low workpace control and low support was significantly associated with higher systolic blood pressure (p<0.05). None of the job title-based scores and their interactions were significantly associated with any of the CHD risk factors (p>0.05).
Conclusion: Our study suggests that individual and work group-based assessments of job strain measure different aspects of job strain in terms of the relationship with CHD risk factors, e.g., individual vs. collective job strain. Job title-based assessments might be less sensitive to measure job strain within blue-collar occupations. The results might also be due to difference in the reliability of these assessment measures.