Background: To evaluate the benefits of collecting patient-reported outcome measures (PROMs) in clinical practice, we assessed the ability of the SIS-16 to detect changes over time compared to the provider-reported modified Rankin scale.
Methods: Observational cohort study of 3,308 ischemic stroke patients seen in a cerebrovascular clinic 9/14/12 - 6/16/15 who completed the routinely collected PROMs: Stroke Impact Scale 16 (SIS-16), EQ-5D, PHQ-9, PROMIS Physical Function (PF), and PROMIS Fatigue. Providers completed the NIHSS and modified Rankin (mRankin). We calculated spearman correlations for all outcome measures. For the 1,455 patients with ≥ 2 visits, we calculated the proportion with meaningful change (SIS-16 ≥8, PROMIS PF and Fatigue ≥ 5, NIHSS ≥2, mRankin ≥1, PHQ-9 ≥ 5, EQ-5D ≥ 0.11). To provide insight on whether changes seen in the SIS-16 and mRankin represented true change in patient status, we calculated the proportion of change in other measures among subgroups with change in SIS-16 and no change in mRankin and for those with a change in mRankin and no change in SIS-16.
Results: Median SIS16 was 85.9, median mRankin was2. Correlations between mRankin and PROMs was highest for SIS-16 (r= -0.64). Of patients with worsening or improvement in SIS-16 and no change in mRankin, significantly more patients had worsening or improvement in other measures, respectively, compared to those with stable SIS-16 and mRankin. In contrast, in those with worsening or improvement in mRankin but no change in SIS-16, there was no corresponding increase in % with change in other measures compared to those with stable SIS-16 and mRankin. (Figure)
Conclusion: PROMs provide additional information compared to the mRankin alone. Changes in the SIS-16 corresponded to changes in other outcome measures, while changes in mRankin did not. This may be due to better ability of SIS-16 to identify change in functional status.