The PROMIS Physical Function Scale: A Promising Scale for Use in Patients with Ischemic Stroke

Objective: To evaluate the performance of the Patient Reported Outcomes Measurement Information System (PROMIS) physical function (PF) scale compared to the validated Stroke Impact Scale-16 (SIS-16) in ischemic stroke patients seen in an ambulatory cerebrovascular clinic.

Methods: This was a retrospective cohort study. PROMIS PF (computer adaptive testing version) and SIS-16 measures were electronically collected on 1,946 ischemic stroke patients seen in a cerebrovascular clinic using an electronic platform from September 12, 2012, to June 16, 2015. Distribution of scores was compared to assess ceiling and floor effects. Correlations with other commonly used functional status scales were performed to assess convergent validity.

Results: The SIS-16 and PROMIS PF had a 19.6% and <1% ceiling effect, respectively. Patients completed 16 SIS-16 items and a median of 4 (interquartile range 4-4) PROMIS PF items. Internal consistency of both SIS-16 and PROMIS PF was excellent. The SIS-16 had slightly but significantly higher correlations with the other functional scales than PROMIS PF.

Conclusions: The use of PROMIS to obtain electronic patient-reported functional status in an ambulatory setting is feasible. PROMIS PF is an option for measurement of physical function in ischemic stroke patients. It had similar test characteristics as the SIS-16 but with lower patient burden and minimal ceiling effect.