In this instructive episode, Mo and Marc focus on the concept of the Fragility Index—a method for evaluating the robustness of statistically significant dichotomous outcomes in RCTs—and discuss why this concept is relevant to practicing orthopaedic surgeons, who must routinely make real decisions in the clinic and OR based on their interpretation of the orthopaedic literature. OrthoJOE Mailbag: feedback, comments, and suggestions from our audience can be sent to orthojoe@jbjs.org Links: • OrthoEvidence. Fragility Index: How robust are your results? OE Original. 2021;4(5):2. Available from: https://myorthoevidence.com/Blog/Show/127 • Ekhtiari S, Gazendam AM, Nucci NW, Kruse CC, Bhandari M. The Fragility of Statistically Significant Findings From Randomized Controlled Trials in Hip and Knee Arthroplasty. J Arthroplasty. 2021 Jun;36(6):2211-2218.e1. doi: 10.1016/j.arth.2020.12.015. Epub 2020 Dec 13. PMID: 33390336. https://pubmed.ncbi.nlm.nih.gov/33390336/