The expansion and validation of a new upper extremity item bank for the Patient-Reported Outcomes Measurement Information System® (PROMIS)

Background: The Patient-Reported Outcomes Measurement Information System® (PROMIS) includes a Physical Function (PF) item bank and an Upper Extremity (UE) item bank, which is composed of a subset of items from the PF bank. The UE item bank has few items and known ceiling effects. Therefore, this study aimed to expand the item bank to assess a wider range of functioning. With the additional content, other psychometric properties—improved content validity, item bank depth, range of measurement, and score reliability—were also evaluated. We convened an expert panel to review potential items, and then conducted psychometric analyses on both extant and newly-collected data. Results: Expert focus groups reviewed the PF item bank for items that were “sufficiently” related to upper extremity functioning for inclusion in the expanded UE item bank. The candidate item bank was quantitatively evaluated in a new sample of 600 people. The final items were calibrated in an aggregated dataset (n = 11,635) from two existing datasets, and the newly collected sample. The original UE item bank included 15 items. After expert review and quantitative evaluation, 31 items were added. The combined 46 items were calibrated using item response theory (IRT). Then computer adaptive tests (CATs) were simulated based off of the psychometric results. These indicated that the new UE item bank has an extended measurement range compared to the original version. Conclusions: The expanded PROMIS UE item bank assesses a wider range of upper extremity functioning compared to the initial UE item bank. However, ceiling effects remain a concern for unimpaired groups. The new UE item bank is recommended for individuals with known or suspected upper extremity limitations.