Comparing the new interdisciplinary Health in work intervention to conventional monodisciplinary welfare interventions at Norwegian workplaces: Protocol for a pragmatic cluster-randomized trial (Preprint)

BACKGROUND Musculoskeletal and mental health complaints are the dominant diagnostic categories in long-term sick leave and disability pensions in Norway. Continuing to work despite health complaints is often beneficial, and a good work environment can improve work inclusion for people affected. In 2001, the Norwegian Labour and Welfare Administration (NAV) began to offer inclusive work measures (IWM) to improve the psychosocial work environment, as well as work inclusion of people with health complaints. In 2018, NAV and specialist health services started offering the new collaborative Health in work programme. Its workplace intervention (HIW) presents health- and welfare information that may improve employees´ coping ability regarding common health complaints. It encourages understanding of coworkers´ health complaints and appropriate work adjustments, in order to increase work participation. OBJECTIVE This protocol presents an ongoing, two-arm, pragmatic cluster-randomised trial. Its aim is to compare the effect of monodisciplinary IWM (treatment as usual) and interdisciplinary HIW in terms of changes in overall sickness absence, healthcare utilisation, health-related quality of life, and costs. Secondary objectives are to compare changes in individual sickness absence, psychosocial work environment, job and life satisfaction, health, and health anxiety, both at the individual and the group level. METHODS Data will be collected from national registers, trial-specific registrations and questionnaires. Effects will be explored by difference-in-difference analysis, and regression modelling. Multilevel analysis will visualise any cluster effects by intraclass correlation coefficients. RESULTS Inclusion is completed with 97 workplaces and 1383 individual consents. CONCLUSIONS Data collection will be finished with the last questionnaires to be sent out in July 2023. This trial will contribute to fill knowledge gaps about effectiveness and costs of workplace interventions, thereby benefitting health and welfare services, political decision-makers, and the public and business sectors. CLINICALTRIAL The trial is approved by the Norwegian Regional Committee for Medical and Health Research Ethics and registered in Clinicaltrials.gov (NCT04000035). Findings will be published in reports, peer-reviewed journals and at conferences.