The Canadian Neurological Scale (CNS) is a simple and validated score to assess stroke severity. The CNS can be use by nurses. Lower scores indicate greater stroke severity. The CNS includes the following components: comprehension, level of consciousness, speech and motor function (face, arm and leg). Previous studies showed good to excellent interrater agreement (kappa or weighted kappa scores 0.76-1.00). Stroke severity was categorized as follows: mild (CNS ≥ 8), moderate (score of 5-7) and severe stroke (score of 1-4). Recent studies have assigned a zero score for patients in a coma. Further details can be found in published studies (Cote et al. Neurology 1989; 39: 638-643 and Bushnell et al. Stroke 2001;32:656).
The Canadian Neurological Scale (CNS) and the National Institutes of Health Stroke Scale (NIHSS) are among the most reliable stroke severity assessment scales. The CNS requires less extensive neurological evaluation and is quicker and simpler to administer. A recent study developed and validated a simple formula to convert the CNS into the NIHSS (NIHSS = 23 - 2 x CNS) (Nilanont, Komoltri, Saposnik et al. Cerebrovasc Dis 2010; 30: 120-126).