From numbers to meaningful change: Minimal important change by using PROMIS in a cohort of fracture patients.

ABSTRACT

INTRODUCTION: use of the Patient-Reported Outcomes measurement Information System (PROMIS®) is slowly increasing in patients with a fracture. Yet, minimal important change of PROMIS in patients with fractures has been addressed in a very limited number of studies. As the minimal important change (MIC) is important to interpret PROMIS-scores, the goal is to estimate the MIC for PROMIS physical function (PF), PROMIS pain interference (PI) and PROMIS ability to participate in social roles and activities (APSRA) in patients with a fracture. Secondly, the smallest detectable change was determined. MATERIALS AND METHODS: A longitudinal cohort study on patients ≥ 18 years receiving surgical or non-surgical care for fractures was conducted. Patients completed PROMIS PF V1.1, PROMIS PI V1.1 and PROMIS APSRA V2.0. For follow-up, patients completed three additional anchor questions evaluating patient-reported improvement on a seven point rating scale. The predictive modeling method was used to estimate the MIC value of all three PROMIS questionnaires. RESULTS: Hundred patients with a mean age of 55.4 ± 12.6 years were included of which sixty (60%) were female. Seventy-two (72%) patients were recovering from a surgical procedure. PROMIS-CAT T-scores of all PROMIS measures showed significant correlations with their anchor questions. The predictive modeling method showed a MIC value of +2.4 (n = 98) for PROMIS PF, -2.9 (n = 96) for PROMIS PI and +3.2 (n = 91) for PROMIS APSRA. CONCLUSION: By using the anchor based predictive modeling method, PROMIS MIC-values for improvement of respectively +2.4 points on a T-score metric for PROMIS-PF, -2.9 for PROMIS-PI and +3.2 for PROMIS APSRA give the impression of being meaningful to patients. These values can be used in clinical practice for managing patient expectations; to inform on treatment results; and to assess if patients experience significant change. This in order to encourage patient centered care.