READERS EVALUATION OF EFFECT OF PEER-REVIEW AND EDITING ON QUALITY OFARTICLES IN THE NETHERLANDS TIJDSCHRIFT-VOOR-GENEESKUNDE

Background Academic biomedical journals use peer review and editing to help to select and improve the quality of articles. We have investiga ted whether articles accepted by the Nederlands Tijdschrift voor Genee skunde, the Dutch Journal of Medicine, were improved after peer review and editing (post-acceptance scientific and copy editing). Methods 40 0 readers of the journal (100 each of medical students, recent medical graduates, general practitioners, and specialists) were invited to pa rticipate in a questionnaire survey. The first 25 from each group who agreed to participate were included. We posted a pack containing a set of identically appearing typescripts (ie, blinding) of the submitted, accepted, and published versions of 50 articles that had been publish ed in Ned Tijdschr Geneeskd. Each evaluator received two of the sets o f versions, and each set was evaluated by one person from each group. The package also included two questionnaires: the first was used to co mpare the submitted with the accepted version (25 questions), the seco nd compared the accepted with the published version (17 questions). Th e questions were answered on five-point scales, and were about the qua lity of the articles or were general/overall scores. We analysed the d ata as scores of 3-5 (ie, improvement) versus 1-2. Findings After peer review, the quality in 14 of 23 questions (61%) was significantly imp roved (p=0.03 or smaller). In particular, the overall score and genera l medical value were significantly improved (p=0.00001 for each). Edit ing led to significant improvement in 11 of 16 questions (69%, p=0.017 or smaller), and especially in style and readability (p=0.001 and p=0 .004). Generally, we found no differences between the scores of the fo ur categories of evaluators, 72% of the evaluators correctly identifie d which version was which. Interpretation Evaluations by readers of th e Ned Tijdschr Geneeskd indicated significant improvement of published articles after both peer review and editing. We think that peer revie w and editing are worthwhile tasks. We also think that possible biases would have had a negligible effect on our results (including the fact that we selected the first 25 evaluators who responded, that some eva luators may have read the published version, and that one questionnair e may have looked more scientific than the other, more editorial one).