Short answer: The global peer reviewer shortage stems from an imbalance between skyrocketing manuscript submission volumes and reviewer fatigue, leading to increased invitation declines and extended review turnaround times.
Peer review depends on editors finding appropriate reviewers who are willing and able to assess a manuscript within a reasonable period. When reviewers decline invitations, respond slowly, have conflicts, or lack the required expertise, editors may need to invite additional reviewers. According to the official ICMJE Responsibilities in the Submission and Peer-Review Process guidelines, journals should work to ensure timely processing with available resources and that journals are responsible for systems to select appropriate reviewers.
What is a peer-reviewer shortage?
The term can describe difficulty obtaining enough suitable reviewers for submitted manuscripts. It does not mean every delayed manuscript is caused by a global shortage. Delays can also arise from editorial screening, workload, reviewer conflicts, technical issues, holidays, revisions, or journal-specific workflows.
Why reviewer availability matters
Editors need reviewers with appropriate subject and methodological expertise. ICMJE notes that journals are responsible for systems that select appropriate reviewers and that journals differ in the number and type of reviewers they seek.
Why reviewers decline invitations
Topic outside the reviewer's expertise.
Conflict of interest or other relationship with authors or the work.
Insufficient time.
Existing reviewing workload.
Journal or manuscript is outside the reviewer's priorities.
Other professional or personal commitments.
What a delay can look like
A manuscript may move through several stages: administrative checks, editorial assessment, reviewer invitations, review completion, editorial decision, revision, additional review, acceptance, and production. The duration of each stage varies substantially by journal and manuscript.
What authors can do
Check the manuscript status through the journal system. For a comprehensive look at what happens before submission, read our guide on the Manuscript Submission Process.
Allow the journal the stated or customary processing time before following up.
Send a concise status inquiry when appropriate.
Keep correspondence professional and include the manuscript ID.
If the journal cannot proceed and its policy permits withdrawal, follow the journal's formal withdrawal procedure.
What authors should not assume
A status such as 'with editor' or 'under review' does not provide enough information to infer how many reviewers have accepted an invitation, what reviewers think, or when a decision will be made. Journal status labels differ. To better understand how long these phases generally take, you can read our breakdown of the Academic Publishing Timeline.
What journals can do
ICMJE recommends timely processing and transparent descriptions of peer-review processes. Journals can communicate realistic expectations, maintain reviewer databases, monitor invitations, and respond to reasonable author status requests.
Why reviewer recruitment is also an integrity issue
Reviewers must protect manuscript confidentiality, disclose relevant relationships, and provide constructive and timely assessments. ICMJE emphasizes confidentiality and conflict disclosure, while the COPE Ethical Guidelines for Peer Reviewers provides detailed ethical guidance for reviewers.
Final takeaway
Reviewer availability is one factor in publishing timelines, but it is not the only one. Authors should interpret status information cautiously and rely on the journal's published workflow and direct communications rather than assuming a specific cause for a delay. For ongoing data and performance benchmarks, you can also review our insights on Journal Metrics Overview.
- Manuscript Submission Process
- How to Respond to Reviewer Comments
- Academic Publishing Timeline
- Journal Quality Checklist
Editorial note: Submission systems, journal requirements, and review workflows vary. Check the target journal's current author instructions immediately before submission.