The Swiss Narcolepsy Scale (SNS) is a brief subjective questionnaire that screens for the occurrence of several behavioral symptoms that may be associated with narcolepsy with cataplexy.1

view the sns

Features of the SNS

  • Purpose:

    Designed to screen for a symptom profile that might be suggestive of narcolepsy with cataplexy1

  • Population:

    Patients with EDS in whom the clinician may want to screen for potential narcolepsy with cataplexy2

  • Assessments:

    Measures frequency of 5 potential symptoms1:
    Q1 – Inability to fall asleep
    Q2 – Feeling bad or not well rested in the morning
    Q3 – Taking a nap during the day
    Q4 – Weak knees/buckling of the knees during emotions such as laughing, happiness, or anger
    Q5 – Sagging of the jaw during emotions such as laughing, happiness, or anger

  • Method:

    Patient self-report1

  • Time required:

    Consists of 5 questions and takes only a few minutes to complete1

  • Scoring:

    Frequency for each behavioral complaint is rated on a 5-point scale, from 1, indicating “never,” to 5, indicating “almost always.” Each question is weighted by a positive or negative factor, with the score calculated using the following validated equation: (6×Q1 + 9×Q2 – 5×Q3 – 11×Q4 – 13×Q5 +20).1,2

  • Interpretation:

    An SNS score <0 is suggestive of narcolepsy with cataplexy.1,2

  • Validation:

    In one study of patients with narcolepsy with cataplexy, an SNS score <0 was shown to have a sensitivity of 96% and specificity of 98%.2

A narcolepsy diagnosis should be established by a sleep specialist with a clinical interview and a nighttime polysomnogram (PSG) followed by a multiple sleep latency test (MSLT). A consistent sleep-wake schedule, including a minimum of 7 hours in bed, should be established for at least 1 week prior to MSLT and PSG, and documented by a sleep log or actigraphy.3

Two narcolepsy screening tools are now available in one app.
Learn More Learn More about the Narcolepsy Screener App

The Swiss Narcolepsy Scale is copyrighted and reproduced with permission of the authors. Unauthorized copying, printing or distribution is strictly prohibited.

+References