Stroke Size Correlates with Functional Outcome on the Simplified Modified Rankin Scale Questionnaire

Background: Acute stroke size is one of the factors impacting functional outcome. To further validate the simplified modified Rankin Scale questionnaire (smRSq), we tested its correlation with stroke size. Methods: We screened 60 ischemic stroke patients with acute brain images available for stroke volume measurement who were enrolled in 2 smRSq reliability studies. Inclusion criteria were acute ischemic stroke visible on computed tomography (CT) or magnetic resonance imaging (MRI) and the smRSq scored at least 3 months after stroke. We excluded patients with disabilities from a previous stroke. One investigator who was blinded to the functional outcomes measured stroke volumes with a specialized computer program (Analyze). We used MRI when both MRI and CT were available. We classified strokes into 2 size categories: lacunar type measuring <= 6.28 cm(3), which corresponds to a cylinder with a maximum diameter and height of 2.00 cm, or strokes >6.28 cm(3). The Spearman correlation analysis compared the smRSq between the lacunar type and the larger strokes. Results: Thirty-two patients qualified for this analysis with a mean age of 59 +/- 15 years, and 17 (53%) were men. Lacunar stroke volumes (n = 17) ranged from 0.03 to 4.58 cm(3), and the larger stroke volumes (n = 15) ranged from 11.52 to 250.02 cm(3). Lacunar strokes were associated with lower smRSq scores (median 1) than the larger strokes (median 4; r = 0.68; R-2 = 0.46; P <.001). Conclusions: Acute stroke size correlates well with the smRSq, supporting its validity in assessing functional outcome after stroke.