A methodological quality review of citations of randomized controlled trials of diabetes type2 in leading clinical practice guidelines and systematic reviews

Objective Evaluate methodological quality of type 2 diabetes RCTs conducted in Iran and cited in clinical practice guidelines and systematic reviews and meta-analyses.Methods We conducted a descriptive methodological quality review, analyzing 286 Randomized Controlled Trials (RCTs) on diabetes mellitus published in Iran from July 2004 to 2021. We searched six databases systematically and evaluated eligible articles using the CONSORT 2010 checklist for abstracts. Two investigators assessed the data using a 17-item checklist derived from CONSORT. Additionally, we examined the citations of each RCT in 260 clinical practice guidelines, with a specific focus on the adequate reporting of outcomes.Results Out of 6667 articles, 286 analyzed. Poor reporting and failure to meet criteria observed. Only 3.8% cited in guidelines. Reporting rates: primary outcomes (41.9%), randomization (61.8%), trial recruitment (12.6%), blinding (50.8%). 27.9% cited in systematic reviews, 50.34% in systematic reviews and meta-analyses, 26.57% in meta-analyses. 67.8% of papers cited in systematic reviews. Adherence highest for participants, objective, randomization, intervention, outcome; lowest for recruitment, trial design, funding source, harms, and reporting primary outcomes.Conclusions Poor methodological reporting and adherence to CONSORT checklist in evaluated RCTs, especially in methodological sections. Improvements needed for reliable and applicable results in guidelines, reviews, and meta-analyses. Inadequate outcome reporting challenges researchers, clinicians, and policymakers, impacting evidence-based decision-making. Urgent improvements in RCT registration necessary.