Edinburgh Research Explorer

Transparency in surgical randomised controlled trials: cross-sectional, observational study

Research output: Contribution to journalArticle

Related Edinburgh Organisations

Open Access permissions



  • Download as Adobe PDF

    Final published version, 339 KB, PDF document

    Licence: Creative Commons: Attribution (CC-BY)

Original languageEnglish
JournalBMJ Open
Publication statusPublished - 15 Aug 2020


Objective To explore transparency in surgical randomised controlled trials with respect to trial registration, disclosure of funding sources, conflicts of interest, and data sharing.
Design Cross sectional review of published randomised controlled trials.
Setting Surgical randomised controlled trials involving human participants undergoing any kind of invasive surgery
Data sources Ten high impact journals were systematically searched for randomised controlled trials, published in the years 2009, 2012, 2015, and 2018. Data was extracted following manual inspection of manuscripts.
Main outcome measure Four domains of transparency were explored. These included trial registration on a public-accessible database, presence of a funding statement, presence of a conflict of interest statement, and presence of a statement relating to data sharing.
Results Of 611 published trials, 475 were eligible for analysis. Three-hundred and ninety-seven (83.6%) were registered, of which 190 (47.9%) were done prospectively. Compliance to prospective registration increased over time (26.0% in 2009, 33.0% in 2012, 53.5% in 2015, and 72.7% in 2018). Funding statements were provided in 55%, 65%, 69.4%, and 75.4% of manuscripts, respectively. Conflicts of interest statements were provided in 49.5%, 89.1%, 94.6%, and 98.3% of manuscript, respectively. Data sharing statements were present in only 15 (3.2%) RCTs. Eleven of these were in studies published most recently in 2018.
Conclusion Trial registration, presence of funding statements, and disclosure of personal conflicts in surgical RCTs have improved rapidly over the last 10 years. In contrast, disclosure of data sharing plans is exceptionally low. This may contribute to research waste and represents an essential target for improvement.

Strengths and limitations of this study
• Surgical RCTs published between 2008-2018 were considered in this study, which permitted an assessment of transparency over time.
• Included RCTs were from a sample of high impact surgical and general medical journals, which restricts the generalisability of findings across a broader population

• The study considered author-reported statements of funding, conflicts, and data sharing, which may introduce bias or inaccuracies due to self-reporting.

Download statistics

No data available

ID: 131009735