Reporting of Animal Studies on Craniofacial Bone Repair: 2004, 2014, and 2024

Clinical need and research activities on craniofacial bone repair/regeneration (CBR) have been increasing in dentistry, and animal research provides essential support for its advancement. However, inadequate reporting in animal research contributes to avoidable research waste and limits the validation and translation of research findings. Therefore, this research-on-research study aimed to assess the reporting quality of animal research on CBR and to identify its changes over the past 2 decades. Electronic and manual searches were conducted to identify animal research regarding CBR published in 2004, 2014, and 2024. The reporting quality of included studies was assessed using a modified ARRIVE (Animal Research: Reporting In Vivo Experiments) 2.0 checklist. A multivariable generalized linear model was used to explore changes in reporting quality over time. A total of 164 studies were included. The mean (standard deviation) overall quality score (OQS; calculated by summing the scores of all checklist items) improved over time: OQS₂₀₀₄ = 4.42 (1.29), OQS₂₀₁₄ = 5.70 (1.72), and OQS₂₀₂₄ = 6.79 (2.25). Among the included studies, "study design," "objectives," and "generalizability" were adequately reported. In contrast, less than 1.0% of the included studies sufficiently reported "inclusion and exclusion criteria" (0.6%; 1/164) and "protocol registration" (0.6%; 1/164). Despite the release and update of the ARRIVE guidelines, several methodological items, including "sample size" (8.5%; 14/164) and "randomization" (6.7%; 11/164), remained poorly reported. Only 18 of 164 studies (11.0%) specified the primary outcome measures, and none reported effect sizes with confidence intervals. Reporting of "ethical statements," "data access," and "declaration of interests" considerably improved but remained suboptimal. According to the multivariable analysis, publication year was a significant predictor of reporting quality (P < 0.01). The reporting of CBR animal research has improved significantly during the past 2 decades. However, concerted efforts toward more complete and transparent reporting, which facilitate validation and translation, are warranted.