Improving the quality of reports of meta-analyses of randomised controlledtrials: the QUOROM statement

Background: The Quality of Reporting of Meta-analyses (QUOROM) conference w as convened to address standards for improving the quality of reporting of meta-analyses of clinical randomised controlled trials (RCTs). Methods: The QUOROM group consisted of 30 clinical epidemiologists, clinici ans, statisticians, editors, and researchers. In conference, the group was asked to identify items they thought should be included in a checklist of s tandards. Whenever possible, checklist items were guided by research eviden ce suggesting that failure to adhere to the item proposed could lead to bia sed results. A modified Delphi technique was used in assessing candidate it ems. Findings: The conference resulted in the QUOROM statement, a checklist, and a flow diagram. The checklist describes our preferred way to present the a bstract, introduction, methods, results, and discussion sections of a repor t of a meta-analysis. It is organised into 21 headings and subheadings rega rding searches, selection, validity assessment, data abstraction, study cha racteristics, and quantitative data synthesis, and in the results with 'tri al flow', study characteristics, and quantitative data synthesis; research documentation was identified for eight of the 18 items. The flow diagram pr ovides information about both the numbers of RCTs identified, included, and excluded and the reasons for exclusion of trials. Interpretation: We hope this report will generate further thought about way s to improve the quality of reports of meta-analyses of RCTs and that inter ested readers, reviewers, researchers, and editors will use the QUOROM stat ement and generate ideas for its improvement.