Data sharing and transparency indicators in published RCTs in Oral Health between 2017 and 2023

Objectives: To record the proportion of data sharing reporting in terms of primary data and/or statistical code of Randomized Controlled Trials (RCTs), published across 12 high impact journals in Dentistry, covering 6 specialty domains. Associations with certain journal, publication and outcome characteristics were examined. Transparency indicators such as registration or funding statements were assessed. Methods: We identified and included all RCTs published from January 1st, 2017 to December 31st, 2023 in journals of high impact of the following domains: Periodontology, Endodontics, Restorative Dentistry/Prosthodontics, Orthodontics, Pediatric Dentistry, Oral/Maxillofacial Surgery. The primary outcome was the proportion of RCTs reporting their intent to share or openly shared primary data and we tested for associations with potential predictors. Funding, registration, and statistical code/script sharing practices were also examined. Results: A total of 752 RCTs were included, of which only 119 (15.8%) either openly provided their data or included a statement of intention to share upon request. Only one study openly provided the statistical code underlying the analysis used. RCTs in periodontology more frequently included statements about positive intent to share (57/210;27.1%), followed by Orthodontics (35/157;22.3%). Significant effects of year, dentistry domain and continent of authorship on data sharing practices were identified (p < 0.001 in all cases). There was evidence that registered RCTs had 2.04 times higher odds for intention to share data (95%confidence interval: 1.06, 3.92;p = 0.03). Conclusions: Overall, in oral health RCTs, empirical evidence suggested very low prevalence of positive data sharing practices. Enhancing transparency is pivotal in promoting reproducibility and credibility of research findings. Clinical significance: The findings of this empirical report bring attention to key transparency indicators in randomized controlled trials. These largely impact on the credibility and reproducibility of the evidence base for clinical decision making.