Delayed publication of clinical trials in cystic fibrosis

Abstract

Background: When the publication of important trial data is delayed, or data are never published, this will prevent the proper practice of evidence based medicine through robust systematic reviews. Clinical trial registries allow researchers to interrogate the trial protocol and afford the opportunity to identify studies that have been completed and so determine the time lag between completion and publication.

Methods: We searched ClinicalTrials.gov with the keywords 'cystic fibrosis'. Intervention trials which had completed 1st Jan 1998-31st Dec 2010 were selected. Time to publication in a peer-reviewed journal was calculated. Survival analyses using the log rank test were undertaken.

Results: We identified 142 records. Of these, 62 had full paper publications. The median time to publication was 3.25 years. Phase of study (phase one studies more delayed, p=0.024) but not source of funding (p=0.34) was associated with time to publication.

Conclusions: Clinical trials in cystic fibrosis take a considerable amount of time to report their findings. More importantly, a large number of trials fail to report at all.