Modified Rankin Scale (mRS) is widely used as an indicator of physical disability after the onset of stroke and a main evaluation scale in clinical stroke trials but sometimes has discrepancies among raters. We designed a Japanese version of simplified mRS questionnaire (J-RASQ) to evaluate mRS using closed question to assess the difference from the original. Currently there are no Japanese version of mRS questionnaire and its validity and reliability assessment has been warranted. Patients with planned visit to our hospital between 60 and 120 days after the onset of cerebral hemorrhage or infarction between August 2017 and March 2018 were recruited. J-RASQ was distributed before the outpatient visit to stroke patients, families or caregivers, and response was obtained. Thereafter, outpatient attending physicians qualified as stroke or neurological specialists evaluated mRS according to the Japanese version of guidance scheme for mRS. Subsequently, 130 patients (mean age, 72 ± 12 years old) were enrolled, and the difference between the two scale scores (mRS vs. J-RASQ) were statistically examined by the κ statistic and the weighted κ statistic. The κ statistic was 0.42 (95% CI, 0.31-0.52), and the weighted κ statistic calculated taking into account the extent of disagreement was 0.78 (95% CI, 0.70-0.86). We conclude that the J-RASQ appears to have decent reliability and is similar to the existing mRS.
Keywords: modified Rankin Scale; questionnaire; reliability; κ statistic.