Comparison of reporting phase III randomized controlled trials of antibiotic treatment for common bacterial infections in ClinicalTrials.gov and matched publications.

OBJECTIVES: Discrepancies between ClinicalTrials.gov entries and matching publications were previously described in general medicine. We aimed to evaluate the consistency of reporting in trials addressing systemic antibiotic therapy.

METHODS: We searched ClinicalTrials.gov for completed phase III trials comparing antibiotic regimens until May 2017. Matched publications were identified in PubMed. Two independent reviewers extracted data and identified inconsistencies. Reporting was assessed among studies started before and after 1 July 2005, when the International Committee of Medical Journal Editors (ICMJE) required mandatory registration as a prerequisite for considering a trial for publication.

RESULTS: Matching publications were identified for 75 (70%) of 107 ClinicalTrials.gov entries. Median time from study completion to publication was 26 months (interquartile range 19-42). Primary outcome definition was inconsistent between ClinicalTrials.gov and publications in seven trials (7/72, 10%) and reporting of the primary outcome timeframe was inconsistent in 14 (14/71, 20%). Secondary outcomes definitions were inconsistent in 36 trials (36/66, 55%). Reporting of inclusion criteria and study timeline were inconsistent in 17% (13/65) and 3% (2/65), respectively. Trials started after July 2005 were significantly less likely to have reporting inconsistencies and were published in higher impact factor journals.

CONCLUSIONS: We found a lower inconsistency rate of outcome reporting compared with other medical disciplines. Reporting completeness and consistency were significantly better after July 2005. The ICMJE requirement for mandatory registration was associated with significant improvement in reporting quality in infectious diseases trials. Prolonged time lag to publication and missing data from unpublished trials should raise a discussion on current reporting and publishing procedures.