Randomized Controlled Trials of Carpal Tunnel Release: Robustness and Fragility Index of Published Literature.

BACKGROUND

Many randomized controlled trials (RCTs) have studied outcomes after carpal tunnel surgery, but they have not been scrutinized collectively for their risk of bias or robustness of statistically significant findings. This study applies the fragility index (FI) and bias risk assessments on RCTs for carpal tunnel surgery.

METHODS

A PubMed search was designed to extract English-language carpal tunnel RCTs published between 2003 and 2023. RCTs with dichotomous outcomes, statistically significant results, and a 1:1 parallel treatment arm were included. The FI, fragility quotient, and risk of bias for these trials were calculated, and results were collectively analyzed.

RESULTS

Seven RCTs investigating 11 dichotomous variables were included in this study. The average FI was 1.36 ± 1.12 SD, the average fragility quotient was 0.03 ± 0.03 SD, and the average Jadad score was 3 ± 0.00 SD. The risk of bias determined by means of the Cochrane risk-of-bias tool was moderate in most studies, typically from nonblinding of the treating surgeon.

CONCLUSIONS

Dichotomous variables that are reported in carpal tunnel literature have FIs that are overall lower than the suggested threshold of 2, demonstrating poor overall robustness. The overall risk of bias in these trials was moderate and acceptable. This study indicates that more multicenter trials with larger sample sizes are required to ensure robustness of carpal tunnel RCTs.