Trial Registry Searches in Plastic Surgery Systematic Reviews: A Meta-epidemiological Study

Clinical trial registry searches for unpublished clinical trial data are a means of mitigating publication bias within systematic reviews (SRs). The purpose of our study is to look at the rate of clinical trial registry searches conducted by SRs in the top five Plastic and Reconstructive Surgery journals.

We identified the top five plastic and reconstructive surgery journals using the Google h-5 index. We then searched Pubmed for SRs published in these journals and compared them to plastic surgery SRs published in the Cochrane Collaboration for SRs over the last 5 y. We included all SRs that were published within these top five journals and Cochrane between December 6, 2016 and December 6, 2021. We then conducted a secondary analysis on clinicaltrials.gov looking for unpublished clinical trials for 100 randomized SRs that did not conduct a clinical trial registry search.

In SRs, 3.3% (17/512) from plastic surgery journals conducted trial registry searches. In comparison, 95.0% (38/40) of Cochrane Collaboration SRs conducted trial registry searches. Our secondary analysis found that 50% (50/100) of SRs could have included at least one unpublished clinical trial data set.

We found that plastic surgery SRs rarely include searches for unpublished clinical trial data in clinical trial registries. To improve the data completeness of SRs in plastic surgery journals, we recommend journals alter their author guidelines to require a clinical trial registry search for unpublished literature.