Menke, James Michael DC, PhD SPINE: November 29, 2021 – Volume – Issue – doi: 10.1097/BRS.0000000000004298 Abstract Study Design. The 2001 Functional Rating Index (FRI) was not developed under today’s standard psychometric analysis. The original data of 108 cases, were re-analyzed using Rasch item response theory. In addition, two alternative forms were administered to an […]