Change over five years in important measures of methodological quality and reporting in cardiovascular clinical research trials

Abstract

Abstract Objectives The aim of our current study was to analyze whether important measures of methodological quality and reporting of randomized controlled trials published in the field of cardiovascular disease research changed over time. Further aim was to investigate whether there was an improvement over time in the ability of these trials to provide a good estimate of the true intervention effect. Methods We conducted two separate searches in the Cochrane Central Register of Controlled Trials (CENTAL) database to identify cardiovascular clinical research trials published in either 2012 or 2017. Randomized controlled trials (RCTs) trials in cardiovascular disease research with adult participants were eligible to be included. We randomly selected 250 RCTs for both publication year 2012 and 2017. Trial characteristics, data on measures of methodological quality and reporting were extracted and risk of bias for each trial was assessed. Results As compared to 2012 in 2017 there were significant changes in important measures of methodological quality and reporting, including an improvement in the reporting of the presence of a data monitoring committee (42.0% vs. 34.4%), and a positive tendency of registering cardiovascular disease research RCTs in clinical trial registries (83.6% vs. 72.0%). On the other hand, we also observed that significantly fewer RCTs reported sample size calculation (60.4% vs. 98.4%) in 2017 as compared to 2012. RCTs in 2017 were more likely to have low overall RoB than in 2012 (29.2% vs. 21.2%). However, the 5-year-change was not clearly in the direction of improvement for all RoB domains. In 2017 multicenter trials, drug trials and registered trials were also more likely to have a low overall RoB, than single center, non-drug on non-registered trials. In 2012 specific trial characteristics had not yet a significant impact on overall RoB. Conclusion: As compared to 2012 in 2017 there were significant improvement in some, but not all the important measures of methodological quality. Although more trials in the field of cardiovascular disease research had a lower overall RoB in 2017, the improvement over time was not consistently perceived in all RoB domains.