- INTRODUCTION: Previous research suggests that work with a suitable workload may promote health and work retention in people with disability. This study will examine whether temporary work modifications at the early stage of work disability are effective in enhancing return to work (RTW) or staying at work among workers with musculoskeletal or depressive symptoms. METHODS AND ANALYSIS: A single-centre controlled trial with modified stepped wedge design will be carried out in eight enterprises and their occupational health services (OHSs) in nine cities in Finland. Patients seeking medical advice due to musculoskeletal pain (≥4 on a scale from 0-10) or depressive symptoms (≥1 positive response to 2 screening questions) and fulfilling other inclusion criteria are eligible. The study involves an educational intervention among occupational physicians to enhance the initiation of work modifications. Primary outcomes are sustained RTW (≥4 weeks at work without a new sickness absence (SA)) and the total number of SA days during a 12-month follow-up. Secondary outcomes are intensity of musculoskeletal pain (scale 0-10), pain interference with work or sleep (scale 0-10) and severity of depressive symptoms (Patient Health Questionnaire, PHQ-9), inquired via online questionnaires at baseline and 3, 6, 9 and 12 months after recruitment. Information on SA days will be collected from the medical records of the OHSs over 12 months, before and after recruitment. The findings will give new information about the possibilities of training physicians to initiate work modifications and their effects on RTW in employees with work disability due to musculoskeletal pain or depressive symptoms. ETHICS AND DISSEMINATION: The Coordinating Ethics Committee of Hospital District of Helsinki and Uusimaa has granted approval for this study. The results will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: ISRCTN74743666.