Prospective registration of randomized clinical trials for total shoulder arthroplasty is low: a systematic review

Prospective trial registration has become an important means of improving the transparency and reproducibility of randomized controlled trials (RCTs) and is recommended by the Journal of Shoulder and Elbow Surgery (JSES) per the Consolidated Standards of Reporting Trials (CONSORT) guidelines. Herein, we performed a cross-sectional evaluation of RCTs published in JSES from 2010 to present to determine the prevalence of trial registration and consistency of outcome reporting.

The electronic database PubMed was searched to identify all RCTs on total shoulder arthroplasty (TSA) published in JSES from 2010 to 2022 using the search terms "randomized controlled trial" AND "shoulder" AND "arthroplasty OR replacement." RCTs were considered to be registered if they provided a registration number. For articles that were registered, authors also extracted the registry name, registration date, date of first enrollment, date of last enrollment, and if the primary outcomes reported in the registry were either (1) omitted, (2) newly introduced in the publication, (3) reported as a secondary outcome or vice versa, or (4) varied in timing of assessment compared to the publication. "Early" RCTs were considered those published from 2010 to 2016, whereas "later" RCTs were from 2017 to 2022.

Fifty-eight RCTs met inclusion criteria. There were 16 early RCTs and 42 later RCTs. Twenty-three of the 58 (39.7%) studies were registered, with 9 of 22 with an available registry (40.9%) of those being enrolled prior to patient enrollment. Nineteen of the registered studies (82.6%) provided the name of the registry and a registration number. The proportion of later RCTs that were registered was not significantly different from the early RCTs (45.2% vs. 25.0%, P = .232). Seven RCTs (31.8%) had at least 1 inconsistency compared with the registry. The most common discrepancy was the timing of the assessment (ie, follow-up period) reported in the publication vs. the registry.

Although JSES recommends prospective trial registration, less than half of shoulder arthroplasty RCTs are registered and more than 30% registered trials have at least 1 inconsistency with their registry record. More rigorous review of trial registration and accuracy is necessary to limit bias in published shoulder arthroplasty RCTs.