I read with interest the recent article examining the relationship between job strain and health-related lifestyle factors.1 Given the findings presented in the study I was perplexed by one of the authors' conclusions that
reducing work-related psychosocial stress … is unlikely to be an important target for any policy or intervention aiming to influence health-related lifestyle factors.1(p2095)
This conclusion is misleading for multiple reasons. Most importantly, it does not reflect the findings presented in the study. Job strain and passive work were both associated with a reduced probability of adopting a healthy lifestyle (Figure 1).1 A policy approach that encourages people to adopt a healthier lifestyle could target low job control.
There are also methodological inadequacies in the longitudinal analyses. These include the crude methods used to measure change in lifestyle, whereby a respondent who stops smoking, but continues to be inactive, would be considered to not have engaged in a healthier lifestyle. More rigorous methods to measure change are available2,3 and should be implemented. Furthermore, job strain was only measured on one occasion, likely resulting in weaker relationships that if two assessments had been used.4 And, if the impact of job strain on unhealthy behavior occurs relatively quickly, it would be missed by all the studies included (of which two years was the shortest follow-up). Note that these limitations are in addition to the general limitations associated with the harmonization of job strain and health behavior responses across the various cohorts.5 In light of these methodological deficiencies, it seems premature to dismiss the impact of job strain on health-related lifestyle factors until a more rigorous analysis has been undertaken.
Finally, job strain does not equate to all psychosocial stress.6 It is entirely possible that other dimensions of the psychosocial work environment such as effort–reward imbalance, lack of social support, or organizational injustice may have an even larger impact on health behavior change than job strain does in these analyses.
Individual-level data across multiple cohort studies bring with it great power—both statistically and publication-wise (because of the opportunity to publish relatively simple analyses in top-tier journals). But with power also comes responsibility. The authors involved in the Individual-Participant Data Meta-analysis of Working Populations analyses have the responsibility to present conclusions that are not misleading in relation to the potential importance of job strain, or to implicate other dimensions of the psychosocial-work environment on health behaviors and other health outcomes.
References
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