Replicability and transparency in physical therapy research: Time to wake up

BackgroundOver the past decade, a replication crisis has been recognized in several scientific disciplines, raising concerns about the validity and reliability of published research and eroding scientific credibility. While this crisis has been widely discussed in other fields, its impact on physical therapy research has received little attention. ObjectiveThis study aimed to provide an overview of the current state of physical therapy research practices that could suggest low replicability. MethodsWe assessed the research practices in all original research articles published in official journals of national physical therapy associations in the USA (Physical Therapy), Canada (Physiotherapy Canada), the UK (Physiotherapy), and Australia (Journal of Physiotherapy) between 2022 and 2024. ResultsA total of 465 original research articles were identified. Of these, 28% were preregistered, 0% were replication studies or registered reports, and 12% provided open data. Sample size justification was reported in 37% of quantitative studies and 23% of qualitative studies. Despite an average time from submission to publication of 400 days, only 1% of manuscripts were preprinted. Among quantitative studies, 33% stated a hypothesis, while 63% relied on significance testing. Of the reported significant p-values, 39% fell within the fragile range (.01[&le;] p<.05), substantially exceeding the expected 26% under 80% power and suggesting questionable research practices. Hypotheses were supported in 83% of cases, indicating an unreasonably high rate of positive results. A marked difference in the number of p-values just above and just below the significance threshold suggested publication bias. ConclusionThese results suggest shortcomings in the reproducibility, replicability, and transparency of the physical therapy literature. Addressing these issues requires the adoption of best practices, including registered reports, justifying sample sizes, publishing negative results, and sharing data and code. Delays in implementing these practices risk exacerbating bias in the literature and undermining the scientific credibility of physical therapy research. StatementThis manuscript is a preprint and is not peer-reviewed. All authors have approved this version of the manuscript. CitationJabouille F, Farajzadeh A, Guillemot Exertier A, Martine J, Sadek N, Huet Klinger L, Iliut CM, Kapsa V, & Boisgontier MP. Replicability and transparency in physical therapy research: Time to wake up. MedRxiv. 2025.