Characterization and Potential Relevance of Randomized Controlled Trial Patient Populations in Revision Total Joint Arthroplasty: A Systematic Review

Randomized controlled trial (RCT) studies in revision total joint arthroplasty (rTJA) are essential to investigate the effectiveness of interventions. However, there has been limited research investigating how patient cohorts comprising rTJA RCT samples resemble the U.S. patient population undergoing rTJA in terms of demographic and clinical characteristics. Thus, the purpose of this systematic review was to compare the patient characteristics of rTJA RCT cohorts with the characteristics of national patient database cohorts. RCT studies for rTJA were aggregated. Patient demographics in this group were compared against Healthcare Cost and Utilization Project-National Inpatient Sample (NIS) and American College of Surgeons-National Surgical Quality Improvement Program (ACS-NSQIP) patient cohorts. Forty-six RCTs met inclusion criteria. There were 3,780 total patients across 46 RCTs. The average age of patients in the rTJA RCT cohort was 66.4 +/- 9.4 while in the NIS cohort was 67.3 +/- 11.1 ( d = 0.08, effect size = small). The average body mass index (BMI) of the rTJA RCT cohort was 31.1 +/- 5.7 while the NSQIP cohort was 31.7 +/- 8.3 ( d = 0.08, effect size = small). For rTJA, effect sizes for age, BMI, sex, ethnicity, smoking, and diabetes were all small or very small. Overall, the rTJA RCT patient cohort does not differ significantly compared with the general patient population undergoing rTJA. Differences in demographic and clinical characteristics between the rTJA RCT cohort and database cohorts were minimal to small, indicating that these differences are unlikely to impact clinical outcomes.