Publication of neurology clinical trials registered with clinical trial registry of India: A cross-sectional study

Objectives Unbiased and full disclosure of trial results is vital to evidence-based medicine. Non-publication and selective publication leads to publication bias and unrealistic risk-benefit ratio. In the present study, we aim to determine the publication rate of clinical trials related to neurology registered with the Clinical Trial Registry of India (CTRI), compare the characteristics of published and unpublished trials, and evaluate the adherence of investigators to ethics-approved criteria and outcomes. Materials and Methods A cross-sectional search using the keyword "neurology" was carried out in CTRI registry. Two independent investigators searched Pubmed, Medline, Scopus, and Google Scholar for published manuscripts. The final literature search occurred in November 2021. Results Out of 325 trials, 102 trials were published (31.4%). Ninety-one trials were beyond 3 years of expected time of trial completion and were still unpublished. Randomized trials had a slightly higher publication rate than non-randomized ones (56% vs. 46%, p = .223); however the difference was not statistically significant. Majority of trials sponsored by pharmaceutical companies were not published, while majority of those sponsored by non-pharmaceutical institutions were published (34.5% vs. 69.3%, p < .001). Feedback to CTRI about trial status was particularly poor (31.5% - informed vs. 68.5% - not informed, p < .001). 52 (50.9%) and 65 (63.7%) of the 102 published trials had changed the registered inclusion and exclusion criteria, respectively, in the CTRI registry compared to those in the published manuscript. In 29 (28.3%) of the 102 trials, the primary outcome did not match with that registered in the CTRI and in 73 (57.8%) trials, the secondary outcomes did not match. Conclusion A large proportion of neurology registered trials are still unpublished, with a majority of pharmaceutical company-sponsored trials not being published. There is scope for improving the provisions in CTRI for enlisting trial results, that may prevent publication bias and also ensure the investigators adhere to the pre-specified ethics approved trial procedures and outcomes.