Influence of study sponsorship on head and neck cancer randomized trial results.

BACKGROUND The purpose of this study was to identify associations between study sponsorship and the methodological quality and published outcomes of head and neck cancer randomized controlled trials (RCTs). METHODS We systematically searched MEDLINE, EMBASE, CINAHL, and the Cochrane Central Register of Controlled Trials for qualified RCTs, evaluating journal impact factor (IF), Jadad score (measure of study quality), and results favoring or not favoring experimental therapy. RESULTS Of 118 RCTs, the most common sponsor was government (38; 32%), followed by nonprofit organizations (30; 25%) and industry (26; 22%). Industry-supported RCTs were associated with publication in journals with higher IF compared with RCTs without industry support (p = .013). Government-supported RCTs were associated with higher mean Jadad score (p = .026) and results favoring experimental therapy (p = .034). CONCLUSIONS Government-supported, but not industry-supported, RCTs were significantly associated with positive study results. These findings may be confounded by broadly applied definitions of sponsorship.