Exploring Engagement with Authors of Randomised Controlled Trials to Develop Recommendations to Improve Allocation Concealment Implementation and Reporting

Background: Reviews have consistently shown that allocation concealment is frequently implemented and reported suboptimally in randomised controlled trials (RCTs). This research aims to pilot engaging with authors of RCTs to explore their knowledge and understanding of allocation concealment implementation and reporting to ascertain areas and mechanisms for their improvement. Methods: Authors that published RCTs in core clinical journals in one month in 2019 were identified. Authors were invited to complete questionnaires to elicit their views and experiences on the implementation and reporting quality focussing on allocation concealment. Methodological quality of allocation concealment was evaluated in this sample by assessing adherence to the Consolidated Standards of Reporting Trials (CONSORT). Results: Reporting was suboptimal, with only 57% of allocation concealment methods reported to be implemented which were judged as adequate, with 18% using sealed envelopes and more than 40% not adequately reporting allocation methods. When exploring allocation concealment, implementation and reporting questionnaires were found to elicit a low response rate amongst authors of RCTs. Discussion: Following analysis of the themes that emerged from the questionnaires, the main recommendations to improve reporting quality are: journals need to endorse, adhere and promote reporting guidelines, a methodologist could review methodological details of publications simultaneously to peer review, envelopes as a form of allocation concealment are poorly implemented and reported, so careful review of these is required, funders need to insist on more robust allocation concealment methods are employed if the RCT setting allows, and authors need to acknowledge their responsibility for transparent reporting of RCTs.