Assessment of 30 Years of Randomized Controlled Trials in 1990-2020.

BACKGROUND

Randomized controlled trials (RCTs) stand atop the evidence-based hierarchy of study designs for their ability to arrive at results with the lowest risk of bias. Even for RCTs, however, critical appraisal is essential before applying results to clinical practice.

PURPOSE

To analyze the quality of reporting of RCTs published in ( from 1990 to 2020 and to identify trends over time and areas of improvement for future trials.

STUDY DESIGN

Systematic review; Level of evidence, 1.

METHODS

We queried the database for RCTs published between January 1990 and December 2020. Data pertaining to study characteristics were recorded. Quality assessments were conducted using the Detsky quality-of-reporting index and the modified Cochrane risk-of-bias (mROB) tool. Univariate and multivariable models were generated to establish factors with associations to study quality. The Fragility Index was calculated for eligible studies.

RESULTS

A total of 277 RCTs were identified with a median sample size of 70 patients. A total of 19 RCTs were published between 1990 and 2000 (t); 82 RCTs between 2001 and 2010 (t); and 176 RCTs between 2011 and 2020 (t). From t to t, significant increases were observed in the overall mean-transformed Detsky score (from 68.2% ± 9.8% to 87.4% ± 10.2%, respectively; < .001) and mROB score (from 4.7 ± 1.6 to 6.9 ± 1.6, respectively; < .001). Multivariable regression analysis revealed that trials with follow-up periods of <5 years clearly stated primary outcomes, and a focus on the elbow, shoulder, or knee were associated with higher mean-transformed Detsky and mROB scores. The median Fragility Index was 2 (interquartile range, 0-5) for trials with statistically significant. Studies with small sample sizes (<100 patients) were more likely to have low Fragility Index scores and less likely to have a statistically significant finding in any outcome.

CONCLUSION

The quantity and quality of published RCTs published in increased over the past 3 decades. However, single-center trials with small sample sizes were prone to fragile results.