Study Design
Clinical measurement
Purpose
The Patient-Reported Outcomes Measurement Information System (PROMIS) v1.2 Upper Extremity (UE) item bank was recently developed in response to research demonstrating UE function to be a separate domain from general physical function as measured with PROMIS instruments. In particular, the PROMIS v1.2 UE item bank assesses upper extremity physical function in patients with hand and upper extremity conditions. Though validation on a general sample was conducted prior to its release, the psychometric properties of the PROMIS v1.2 UE item bank have not been fully evaluated in specific populations. This study assesses the performance of the PROMIS v1.2 UE within the UE orthopaedic patient population.
Methods
A total of 1,197 adult patients presenting to a tertiary orthopaedic clinic specializing in hand and upper extremity conditions were administered the PROMIS v1.2 UE items and three other PROMIS scales. Descriptive statistics of patient demographics and item raw scores were performed, as well as Rasch analysis of the PROMIS v1.2 UE item bank.
Results
The PROMIS v1.2 UE item bank fits a unidimensional Rasch model. It demonstrated adequate reliabilities, item local independence and model fit. There was essentially no issue with gender differential item functioning. The test items mostly targeted low levels of function, thus revealing large ceiling effect.
Conclusions
The PROMIS v1.2 UE item bank is a useful clinical assessment tool with good psychometric properties that can be implemented in clinical settings. Consideration should be given to supplemental testing for patients at higher levels of function with other legacy tests until the ceiling effects of the PROMIS v1.2 UE item bank are addressed.