Background: Peer review is a necessary but costly and time-consuming process to identify good-quality and methodologically sound articles and improve them before publication. Finding good peer reviewers is often difficult.

Objective: To identify the incentives that make Iranian biomedical researchers accept invitations to be a peer reviewer and factors that affect these incentives.

Methods: Twelve reviewers selected at random from the reviewers pool of each of 26 biomedical journals published from Fars province, Iran, were surveyed using a questionnaire that we had developed and tested in a pilot study of 30 reviewers (Cronbach’s alpha of 0.779). The data included the reviewers’ demographics, history of their reviews, and choice of 11 reasons each for accepting or declining the invitation to review.

Results: A total of 233 reviewers completed the questionnaire. The most important reasons for accepting the invitation to review were the journal’s practice to publish the names of the reviewers alongside the article they had reviewed, acknowledgement by the journals by publishing the names of reviewers once a year, free access to journals’ content, and lower publication charges as authors. The most common reasons to decline the invitation were lack of time, busy schedules, and lack of sufficient incentive to review.

Conclusion: Acknowledgement by the journal, offering to publish the names of reviewers alongside the articles they had reviewed, and monetary rewards will be effective incentives for biomedical researchers in Iran to serve as peer reviewers.