Evaluating occupational health interventions: Design, implementation, and effects

Background: Poor mental health, e.g. stress, anxiety, and depression, in the workplace is achallenge worldwide due to the individual suffering and its impact on sickness absence andproductivity loss, causing societal costs. The World Health Organisation classifies stress asthe health epidemic of the 21st century. Psychosocial working conditions, i.e., how work isorganised and the social interplay at work, are health determinants. Thus, psychosocialhazards are one explanation for work-related mental ill-health. Interventions aiming toimprove the psychosocial work environment are recommended. Still, there is a scarcity ofstudies evaluating occupational health interventions targeting psychosocial workingconditions to prevent mental ill health. Also, the existing evidence of the effectiveness ofsuch interventions is inconclusive. Implementation failure is described as one main obstacleto succeeding with these interventions. To tackle the global challenges of work-related stress,we need a better understanding of what can be done in the workplace to prevent employeesfrom becoming ill due to workplace stressors.Aim: This thesis aims to contribute to knowledge on how stress-related ill health can beprevented in the workplace and develop our understanding of the design and implementationof occupational health interventions.Methods: This thesis comprises three papers that evaluate two occupational healthinterventions to improve the psychosocial work environment and mental health. Theinterventions were conducted within the human services (I) and construction industry (II &III), respectively.In study I, we applied an embedded mixed methods design to evaluate a participatoryintervention to improve the psychosocial work environment and mental health (burnout andquality of sleep) within a municipality in Sweden. We utilised a controlled trial and a processevaluation exploring fidelity and participants’ reactions to the intervention activities, learningexperiences, and changes in behaviours and work routines. We collected data throughdocumentation, interviews and three waves of questionnaires. Differences in outcome variables(questionnaires) over time were calculated using t-tests for partially overlapping samples tohandle partly different study populations at each time point caused by employee turnover anddrop-out. We analysed the interview data by applying a thematic analysis.The second and third studies were conducted in a large Swedish construction company. Instudy II, we investigated the participants’ satisfaction with engaging in the co-creation process,perceived knowledge, and skill development through interviews. In total, eight men and fourwomen participated. We applied a thematic analysis to analyse the data.In study III, we used a controlled trial to evaluate the potential effects of the co-createdintervention on the psychosocial work environment and self-reported stress. We collected dataon the outcomes with online questionnaires at baseline, 12, and 24 months. We also assessedadherence to the intervention and dose delivered (i.e., fidelity). Marginal means modelsadjusting for missing data patterns were applied to estimate potential differences in outcomesbetween groups over time.Findings: Neither of the interventions improved the long-term outcomes of burnout and stress,respectively. We found different effects of the municipality and construction industryinterventions on the psychosocial working conditions. Within the municipality, we founddetrimental effects of the intervention on social support from the manager, empoweringleadership, control of work pacing, and role clarity. Within the construction industry, there wasa noticeable improvement in role clarity for white-collar workers in the intervention groupcompared to the control group.The implementation fidelity, i.e., whether the intervention activities were delivered accordingto plan, was moderate in both projects. However, the process evaluation within the municipalityproject showed that the intervention activities led to few changes in attitudes, behaviours andwork routines. On the contrary, adherence to the construction industry intervention increasedduring the trial.The results of paper II showed that the co-creation participants reported increased learningabout the psychosocial work environment and mental health. The respondents perceived theintervention and the implementation strategies as relevant and feasible. Thus, involvingdifferent stakeholders and allowing the organisation to decide the intervention activities andthe implementation strategies seem to have enabled a good contextual fit.Conclusions: The program theory, i.e., intervention developed within the constructioncompany, can potentially improve role clarity for white-collar workers. Three design principlesstand out regarding their positive effect on the implementation: organisational capability andincentive systems to promote health, aligning the intervention with existing organisationalobjectives and practices and conducting a needs assessment. The co-creation process in theconstruction industry seems to have positively affected the above-mentioned design principles.Thus, co-creating occupational health interventions seems promising to improve theimplementation.