Redactions in protocols for drug trials: what industry sponsors concealed.

Objective To describe the redactions in contemporary protocols for industry-sponsored randomised drug trials with patient relevant outcomes and to evaluate whether there was a legitimate rationale for the redactions. Design Cohort study. Under the Freedom of Information Act, we requested access to trial protocols approved by a research ethics committee in Denmark from October 2012 to March 2013. We received 17 consecutive protocols, which had been redacted before we got them, and nine protocols without redactions. In five additional cases, the companies refused to let the committees give us access, and in three other cases, documents were missing. Participants Not applicable. Setting Not applicable. Main outcome measure Amount and nature of redactions in 22 predefined key protocol variables. Results The redactions were most widespread in those sections of the protocol where there is empirical evidence of substantial problems with the trustworthiness of published drug trials: data analysis, handling of missing data, detection and analysis of adverse events, definition of the outcomes, interim analyses and premature termination of the study, sponsor's access to incoming data while the study is running, ownership to the data and investigators' publication rights. The parts of the text that were redacted differed widely, both between companies and within the same company. Conclusions We could not identify any legitimate rationale for the redactions. The current mistrust in industry-sponsored drug trials can only change if the industry offers unconditional access to its trial protocols and other relevant documents and data.