Patient-Reported Outcomes Measurement Information System (PROMIS) Global Health Short Forms Demonstrate Responsiveness in Patients Undergoing Knee Arthroplasty

The Patient-Reported Outcomes Measurement Information System (PROMIS) is an alternative to legacy outcome metrics. We investigated the relationship between Knee Injury and Osteoarthritis Outcomes Score for Joint Replacement (KOOS-JR) and PROMIS Global Health forms of Physical Health (PH) and Mental Health (MH) in knee arthroplasty patients.

This is a retrospective cohort study of knee arthroplasty patients from December 2017 through April 2019 who had surveys collected preoperatively and postoperatively. We excluded patients undergoing revision surgery. Outcome scores were analyzed for responsiveness, effect size index (ESI), minimal clinically important difference (MCID), and correlation with each other through 12 months postoperatively.

A total of 875 patients were included. Floor and ceiling effects were 0% for PROMIS-PH. Postoperative PROMIS-PH and KOOS-JR scores significantly correlated with one another and increased from baseline at each postoperative time point ( P < .001 for all). PROMIS-MH did not change between time points ( P > .05). PROMIS-PH showed moderate responsiveness at 1 and 3 months (ESI >0.2) and excellent responsiveness at 6 and 12 months (ESI >0.8), whereas KOOS-JR was responsive at all time points (ESI >0.8). The MCID of PROMIS-PH correlated significantly with KOOS-JR, and a preoperative PROMIS-PH score of less than 32.5 predicted achieving MCID with 97% specificity.

PROMIS global health forms are a valid metric which capture patient outcomes and correlate with KOOS-JR scores after knee arthroplasty. Although KOOS-JR may be more responsive in the early postoperative time period, both measures show excellent responsiveness at 6 and 12 months after knee arthroplasty.