Arthroplasty studies with greater than 1000 participants: analysis of follow-up methods.

backgroundThe use of patient-reported outcome measures (PROMs) has become a mainstay of orthopedic joint arthroplasty research. Large studies with >1000 participants are vital to orthopedic research, as they allow for comprehensive multivariable analysis. Achieving high follow-up rates minimizes potential response bias. Maintaining adequate follow-up rates becomes more challenging as sample size increases. We aimed to systematically review the present literature to determine the follow-up rates of large cohorts/registries of total joint arthroplasty patients and to identify factors associated with successful collection of PROMs.

methodsA comprehensive literature search of PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Inclusion criteria were: ≥1000 participants, ≥6 months of postoperative follow-up, and use of validated PROMs postoperatively.

resultsOf 720 abstracts screened, 21 studies met inclusion criteria. Only 2 studies reported achieving a PROM follow-up rate ≥80%, but neither collected PROMs preoperatively. The median rate of follow-up was 70%, and the median number of patients was 2970. Only 38% (8 of 21) of studies collected baseline PROMs prior to surgery.

conclusionsVery few studies in the present literature have collected validated PROMs on ≥1000 patients with ≥80% follow-up; these parameters are conducive to comprehensive multivariable analysis, while maintaining study validity and avoiding follow-up bias. Federal funding and a central coordinating site may be helpful in achieving follow-up in studies of this magnitude. LEVEL OF EVIDENCE: Level III, systematic review of studies with Level of Evidence I-III.