Editorial Commentary: Illuminating the Fragility of Nonsignificant Trials in Sports Medicine

Orthopaedic clinical research findings can be prone to β error (false negative), owing to small sample sizes. Such trials show no difference between groups when, in fact, a difference may exist. The reverse fragility index is defined as the number of "events" that would cause an individual research study's findings to flip from nonsignificant to statistically significant, and this index can help determine the clinical relevance and validity of clinical trials reporting nonsignificant results. Orthopaedic surgeons should critically evaluate clinical research that shows no statistically significant difference between groups to rule out a β error, given that underpowered studies are particularly prone to fragility. If an orthopaedic trial reports statistically insignificant results, this does not mean the results are clinically insignificant.