Effect of recommendations from reviewers suggested or excluded by authors

The Journal of the American Society of Nephrology (JASN) gives authors submitting original research the option of suggesting qualified reviewers or those they wish to exclude. This historical habit often leaves us wondering whether author preferences correlate with reviewer recommendations and whether differences related to reviewer selection affect decisions by editors. In a self-study presented here, we found that author-suggested reviewers, as a group, make more positive recommendations than editor-suggested reviewers (P = 0.01), although the difference disappears when recommendations are compared with those of editor-suggested reviewers of the same manuscript (P = 0.081). The distribution of recommendations by author-excluded reviewers, as a group, did not differ from those by editor-suggested reviewers; however, author-excluded reviewers impart significantly more negative recommendations than other reviewers of the same manuscript (P = 0.029). We further explored whether such differences result from individual reviewer tendencies to give generally more positive or more negative recommendations than editor-suggested reviewers and found no such tendency. Finally, editorial decisions on manuscripts reviewed by author-suggested or author-excluded reviewers do not differ from those decisions on manuscripts assigned but not reviewed by them. JASN's policy of editors making decisions independent from individual reviewer recommendations minimizes the effect of selection bias on publication decisions.