Comparative Responsiveness of the PROMIS Pain Interference Short Forms with Legacy Pain Measures: Results from Three Randomized Clinical Trials

Abstract

The PROMIS Pain Interference (PROMIS-PI) scales are reliable and publicly accessible; however, little is known about how responsive they are to detect change in clinical trials and how their responsiveness compares to legacy measures. The study purpose was to evaluate responsiveness for the PROMIS-PI scales and to compare their responsiveness with legacy pain measures. We used data from three clinical trials totaling 759 participants. The clinical trials included patients with chronic low back pain (n= 261), chronic back or osteoarthritis pain (n = 240), and a history of stroke (n= 258). At both baseline and follow-up, participants completed PROMIS-PI scales and legacy pain measures (Brief Pain Inventory Interference scale, Pain/Enjoyment/General Activity (PEG) scale, SF-36 Bodily Pain scale, and Roland-Morris Disability Questionnaire). We measured global ratings of pain change, both prospectively and retrospectively, as anchors to identify patients as improved, unchanged, or worsened. Responsiveness was assessed with standardized response means, statistical tests comparing change groups, and area-under-curve analysis. The PROMIS-PI scales had largely comparable responsiveness with the Brief Pain Inventory Interference scale and PEG. The four PROMIS-PI short forms had comparable responsiveness. For all pain questionnaires, responsiveness varied based on the study population and whether pain improved or worsened.