Introduction: Empirical evidence suggests that Cochrane reviews have, on average, greater methodological rigour than systematic reviews or meta-analyses published in paper-based journals (Jadad et al. BMJ 1998; 280: 278-80). Nonetheless there will always be room for improvement.

Objectives: To coordinate the critical reading of Cochrane Reviews currently performed independently by many methodologists in the Cochrane Collaboration; to aggregate and characterise the types of problems identified; to feed back the observations to reviewers and review group editors; to suggest improvements in the peer review processes and in the Cochrane Reviewers Handbook; to suggest ways to ensure continued quality assessment and improvement of Cochrane Reviews.

Methods: Eleven methodologists independently assessed the methodological quality of up to 10 randomly chosen new reviews from The Cochrane Library, issue 98.4. Each review was examined by two methodologists and major or minor problems were documented. If a major problem was noted by one of them, they compared notes and decided whether the reviewers should be given feedback via the Comments and Criticisms system. The feedback was collected at the Nordic Cochrane Centre and common types of problems were identified.

Results: Major problems were identified by at least one methodologist in 16 out of 53 reviews (30%), Five reviews (10%) were considered excellent by both methodologists. The project is ongoing and final results will be presented at the colloquium.

Discussion: Will be presented at the colloquium.