Research waste among randomized controlled trials of delirium: A cross-sectional study

To assess the prevalence, characteristics, and associated factors of research waste among randomized controlled trials (RCTs) of delirium.

Cross-sectional study.

Data derived from ClinicalTrials.gov.

126 phase III/IV delirium RCTs registered between 2000 and 2024.

Publication status was determined via PubMed and Google Scholar. Reporting adequacy was evaluated using the CONSORT reporting guideline checklist, and methodological flaws were assessed using the Cochrane Risk of Bias tool. Research waste was defined as meeting any of the following criteria: non-publication, inadequate reporting (CONSORT compliance <75%), or avoidable design flaws (high/unclear risk per Cochrane criteria).

Research waste was highly prevalent, affecting 92.9% of RCTs. Only 22.2% of trials were fully published. Among published trials, reporting rates for key methodological details (allocation concealment, blinding) were below 80%, and 67.9% had avoidable design flaws. A large sample size (≥100 participants) was independently associated with a higher likelihood of publication (adjusted OR=4.23, 95% CI: 1.43-14.41, P = 0.013), whereas industry or other external funding was associated with a lower likelihood (adjusted OR=0.05, 95% CI: 0.00-0.53, P = 0.027). International and multicenter designs showed a trend toward reducing research waste but were not statistically significant in the multivariate model.

Phase III/IV delirium RCTs exhibit severe research waste, highlighting a critical gap in evidence generation for this geriatric syndrome. Mandating disclosure of results, enhancing reporting transparency, and prioritizing high-quality, large-scale collaborative research are urgently needed to optimize resource allocation and improve outcomes for this vulnerable population.