Canadian Neurological Scale
Original Editor - Sophia Elina Potthoff
Top Contributors - Sophia Elina Potthoff, Uchechukwu Chukwuemeka, Vidya Acharya and Alexandra Stead
Introduction
The Canadian Neurological Scale (CNS) is an assessment tool which was developed by Côté et al. in 1986 to monitor cognitive and motor performance in patients following a stroke.[1] It was designed around four key principles:[1]
- the ability to detect clinically meaningful changes in neurological status
- focus on the functional domains most commonly affected in acute stroke and most likely to carry prognostic value
- ease of use and interpretation across examiners with varying levels of clinical training
- brevity and practicality suited to the acute stroke setting
In practice, the CNS can usually be completed within 5 to 10 minutes.[1] Its actual purpose lies in ongoing monitoring of neurological status. It can be carried out by nursing staff as well as physicians.[1]
Intended Population
The CNS is used for patients with acute stroke who are alert or drowsy.[1] Before applying the CNS, the examiner checks the patient's baseline arousal state. If the patient is stuporous or comatose, the CNS is not used at all. The Glasgow Coma Scale takes over instead.[1]
Method of Use
The scale assesses the level of consciousness, orientation, speech, and motor function. The motor section is divided into A1, if the patient is able to follow commands, and A2, if there is a deficit in comprehension. Therefore aphasia is an important component of the CNS, as language impairment is directly incorporated. [1]
For section A1 and A2, it is important to note that only the weaker side is used to calculate the final score.[1]
The total score falls somewhere between 1.5 and 11.5, with lower values reflecting more severe neurological impairment.[1]
Based on the information presented by Côté et al.[1], the following tables provide a structured summary of the relevant content.
| Item | Finding/Score |
|---|---|
| level of consciousness | alert (3), drowsy (1.5) |
| orientation (place/time) | oriented (1), disoriented or non applicable (0) |
| speech (receptive/expressive language) | normal (1), expressive deficit (0.5), receptive deficit (0) |
| Item | Finding/Score |
|---|---|
| face (show teeth/gums) | none (0.5), present (0) |
| arm proximal (abduction arms to 90°) | none (1.5), mild (1), significant (0.5), total (0) |
| arm distal (make fists and extend wrists) | none (1.5), mild (1), significant (0.5), total (0) |
| leg proximal (hip flexion with knees flexed 90°) | none (1.5), mild (1), significant (0.5), total (0) |
| leg distal (dorsiflexion foot) | none (1.5), mild (1), significant (0.5), total (0) |
| Item | Finding/Score |
|---|---|
| face (mimic grin or grimace elicited by sternal pressure) | symmetrical (0.5), asymmetrical (0) |
| arms (arms 90° in front) | equal (1.5), unequal (0) |
| legs (hip flexion with knees flexed 90°) | equal (1.5), unequal (0) |
Section B - Glasgow Coma Scale
Use this Section only if the patient is stuporous or comatose.
For a detailed guide on how to administer and score the CNS, please watch the instructional video below. This provides a step-by-step guidance on completing the assessment and applying the scoring system in clinical practice.
Evidence
Although some of the references cited in this article date back to the 1980s, they were retained because they represent the original and foundational studies on the CNS. In particular, the studies by Côté et al. provide important evidence regarding the development and initial evaluation of the scale and therefore remain relevant to the present work.[1][3]
Reliability
The reliability of the CNS was assessed by Côté et al. (1989), who found good agreement between two raters. Interrater reliability between two neurologists was excellent (ICC = 0.97), and agreement between nurse and physician rating was also high (r =0.924).[3] Similarly, Stavem et al. (2003) found high inter-rater reliability when the CNS was scored retrospectively from medical records with kappa values ranging from 0.76 to 0.96.[4] A seperate systematic review comparing reliability across nine commonly used stroke scales identified the CNS, alongside the NIHSS (National Institutes of Health Stroke Scale) and the European Stroke Scale, as having the highest reliability of the scales assessed.[5] Overall these findings suggest that the CNS can be applied consistently by different raters, both during direct assessment and when using information from medical records.
Validity
Regarding validity, the CNS was compared with a standard neurological examination and found a correlation of 0.775 between the total CNS score and the overall neurological assessment. This supports the concurrent validity of the scale.[3] Further evidence shows moderate to strong correlations (0.54-0.85) between retrospectively assessed CNS scores and corresponding scores from the Scandinavian Stroke Scale. In addition, the total CNS score was able to predict mortality at 30 days and one year after stroke.[4] These findings support the validity of the CNS as a measure of stroke severity and suggest that it may also provide useful information about prognosis.
Responsiveness
To evaluate responsiveness Côté et al. monitored patients in a neurological intensive care unit over the first 48 hours.[3] They compared the doctors' clinical judgement of whether a patients condition had stayed the same or changed with the actual changes in the CNS score. A change of one point or more in the total score was found to be the best cut-off point for telling stable and changed patients apart.This cut-off point correctly identified almost all patients whose condition had truly changed (sensitivity = 0.933) and rarely missed a real change (negative predictive value = 0.969). However, it was less good at avoiding false alarms, since many patients with a score change of 1 or more had not actually changed clinically (specificity = 0.508).[3]
Links
This link provides the CNS form.
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 Côté R, Hachinski VC, Shurvell BL, Norris JW, Wolfson C. The Canadian Neurological Scale: a preliminary study in acute stroke. Stroke. 1986;17(4):731-737.
- ↑ Heart & Stroke Foundation of Canada. Canadian Neurological Scale Training [Internet]. (accessed 29. July 2026)
- ↑ 3.0 3.1 3.2 3.3 3.4 Côté R, Battista RN, Wolfson C, Boucher J, Adam J, Hachinski V. The Canadian Neurological Scale: validation and reliability assessment. Neurology. 1989;39(5):638-643.
- ↑ 4.0 4.1 Stavem K, Lossius M, Rønning OM. Reliability and validity of the Canadian Neurological Scale in retrospective assessment of initial stroke severity. Cerebrovasc Dis. 2003;16(3):286-291.
- ↑ D'Olhaberriague L, Litvan I, Mitsias P, Mansbach HH. A reappraisal of reliability and validity studies in stroke. Stroke. 1996;27(12):2331-2336.