The Simplified mRS Questionnaire Reflects Stroke Severity

Abstract

Despite some subjectivity and suboptimal reliability, the modified Rankin Scale (mRS) is currently a preferred clinical outcome measure after stroke (1). The mRS measures global functioning after stroke on a broadly defined ordinal scale from zero for complete recovery to five for bedridden, and six for death. We recently developed and tested the simplified mRS questionnaire (smRSq) to help score the mRS more rapidly and reliably than the standard mRS interview, including via telephone (2). Also, a Chinese version of the smRSq has good to excellent clinimetric properties (3). The smRSq correlates well with stroke severity according to the initial National Institutes of Health Stroke Scale (NIHSS) scored remotely via telestroke (4). To test further the validity of the smRSq, we correlate it here with the initial NIHSS scores derived from on-site neurological examinations. Of 41 consecutive patients treated with intravenous tissue plasminogen activator for acute stroke at one Primary Stroke Center, clinical outcomes 3–7 months after stroke were available for 21. One NIHSS certified rater (A. G.) derived the initial NIHSS retrospectively from the neurological examinations documented in the medical records, using a validated algorithm (5) and unaware of the smRSq scores. One mRS certified rater (B. C.) scored the smRSq via telephone (2), unaware of the initial NIHSS scores. The 21 patients had a mean age of 72 years and an initial median NIHSS score of 13. Their median smRSq score 3–7 months after stroke was 5 and mortality was 8/21 (38%). Figure 1 shows good correlation between the initial NIHSS and the subsequent smRSq (multiserial correlation coefficient r = 0·61, R = 0·37, P < 0·003). This adds to the validity of the smRSq. The smRSq offers a rapid, reliable, and valid method of scoring the mRS after stroke, including via telephone.