Psychometric Characteristics and Validity of the PROMIS Cancer Function Brief 3D Profile

Objective: To develop an item response theory (IRT)–calibrated, patient-reported outcome measure (the PROMIS Cancer Function Brief 3D Profile) of physical function, including associations with fatigue and social participation, in cancer rehabilitation patients. Design: Large-scale field testing, graded response model IRT analyses, and multivariate regression analysis. Setting: Six cancer rehabilitation clinics associated with cancer centers across the United States. Participants: Adults (N=616) treated in outpatient cancer rehabilitation medicine clinics. Intervention: Not applicable. Main Outcome Measures: The PROMIS(r) Cancer Function 3D Profile (including existing items from PROMIS(r) item banks). Results: A total of 616 patients completed 21 items in the initial item pool. Nine items were removed because of comparatively lower information that they provide according to the IRT item calibrations, low item-total correlations, or bimodal distributions. The remaining items generated a 12-item short form. Regression analyses determined that the items were responsive to and representative of the patient population across trait ranges and multiple domains and subdomains of function. Conclusions: This psychometric investigation supports the use of the PROMIS Cancer Function Brief 3D Profile for evaluating function in outpatient cancer rehabilitation patients.