Objectives This study aimed to evaluate the process of implementation of a peer coaching intervention program for occupational physicians (OPs) to improve the execution of preventive tasks. Specifically, the evaluation seeks to: (1) describe the reach and uptake of the intervention program; (2) determine the extent to which the program was implemented as intended; (3) provide insights into experiences of OPs, and (4) identify factors influencing the implementation. Methods This study employed a mixed-methods approach to assess seven main process indicators: acceptability, adoption, appropriateness, feasibility, fidelity, penetration and sustainability. Data were collected between March and June 2024 by means of an online questionnaire (N=98), and 17 semi-structured interviews with group coordinators and OPs. Results 20 out of 21 groups allocated to the intervention program participated in the intervention and 98 out of 115 participants (85%) filled in the questionnaire. Three-quarters of the participants completed the entire program. 96% of the OPs successfully discussed barriers to the execution of preventive tasks, and 83% were able to formulate strategies for these barriers. Most participants managed to implement their formulated goals in practice. When they were unable to do so, time constraints and resistance from employers and their occupational health services often played a role. OPs valued the program’s structure, interaction with colleagues, and the increased awareness it generated. Discussion and conclusion The peer coaching group program was well-implemented and positively evaluated by OPs. The program can be improved by allocating more time to it, for instance by integrating it into the educational curriculum, and by paying more attention to the specific working conditions of OPs, such as the different sectors in which they are employed.

The authors have declared no competing interest.

Trial registration: ISRCTN registry ISRCTN15394765. Registered on 27 June 2023.

The author(s) received no specific funding for this work.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The Medical Ethics Review Committee of the Academic Medical Center Amsterdam, the Netherlands, confirmed that the Medical Research Involving Human Subjects Act (WMO) does not apply to the study and that an official approval of this study was not required (reference number W22_415 # 22.490).

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All datafiles will be available from the data.rivm.nl database after completion of the study.