The quality of reporting of randomised controlled trials in asthma: a systematic review

BACKGROUND: There are concerns about the reporting quality of asthma trials. AIMS: To describe the reporting of contemporary asthma trials and to identify factors associated with better reporting quality. METHODS: Two reviewers independently searched MEDLINE for randomised controlled trials (RCTs) of asthma published between January 2010 and July 2012 in leading generalist and specialist journals. We calculated the proportion of trials that adequately reported each Consolidated Standards of Reporting Trials (CONSORT) checklist item and an overall quality score for each trial. Factors associated with better reporting quality were investigated. RESULTS: Thirty-five RCTs satisfied our eligibility criteria. Four trials adequately reported <50% of the items, 15 adequately reported 50–60% of items, and 16 adequately reported >60% of items. Seventeen of the 38 CONSORT items were consistently well reported in more than two-thirds of the articles. In contrast, nine items were poorly reported in more than half the trials — namely, identification as a randomised trial in the title (40.0%), an adequate structured summary/abstract (48.6%), details of eligibility criteria (34.3%), recruitment (48.6%), randomisation procedures (22.9%), intervention (38.5%), harms (34.3%), the funding source (45.7%), and access to the full trial protocol (17.1%). Studies led by teams in high-income country settings were associated with better quality of reporting (relative risk=1.33, 95% CI 1.09 to 1.64). CONCLUSIONS: The quality of reporting in contemporary asthma literature remains suboptimal. We have identified important areas in which reporting quality needs to be improved.