Objective: The aim of this systematic review is to estimate: (i) the overall effect of blinding models on bias; (ii) the effect of each blinding model; and (iii) the effect of un-blinding on reviewer's accountability in biomedical research proposals. Methods: Systematic review of prospective or retrospective comparative studies that evaluated two or more peer review blinding models for biomedical research proposals/funding applications and reported outcomes related to peer review efficiency. Results: Three studies that met the inclusion criteria were included in this review and assessed using the QualSyst tool by two authors. Conclusion: Our systematic review is the first to assess peer review blinding models in the context of funding. While only three studies were included, this highlighted the dire need for further RCTs that generate validated evidence. We also discussed multiple aspects of peer review, such as peer review in manuscripts vs proposals and peer review in other fields.
Keywords: biomedical sciences; blinding; grants; manuscripts; peer review; proposals.