Dr. David Bell's Disability Scale

Still the best disability scale for ME/CFS

  1. Cort
    Resource Type:
    Questionnaire
    This is a summary of a CFIDS disability scale from The Doctor's Guide to Chronic Fatigue Syndrome by David S. Bell, MD, published by Addison-Wesley, ISBN 0-201-40797-2. Dr. Bell treated people with ME/CFS for many years.

    100: Patient has no symptoms at rest, no symptoms with exercise; has normal overall activity; is able to work full-time without difficulty.

    90: Patient has no symptoms at rest, has mild symptoms with activity; has a normal overall activity level. The patient is able to work full-time without difficulty.

    80: Patient has mild symptoms at rest, symptoms worsened by exertion. Patient has minimal activity restriction noted for exertion activities only; patient is able to work full-time with difficulty in jobs which require exertion.

    70: Patient has mild symptoms at rest. Patient clearly notes some daily activity limitation. Overall, the patient functions close
    to 90% of expected, except for activities requiring exertion. Ability to work full-time with difficulty.


    60: Patient has mild to moderate symptoms at rest, with daily activity limitation clearly noted. Overall functions 70-90%. Patient is unable to work full-time in jobs which require physical labor, but has the ability to work full-time in light activity if hours are flexible.

    50: Patient has moderate symptoms at rest, and moderate to severe symptoms with exercise or activity. An overall activity level is 70% of expected. Patient is unable to perform strenuous duties, but can perform light duty, or desk-work 4-5 hours per day, requires rest periods.

    40: Patient has moderate symptoms at rest, and moderate to severe symptoms with exercise activity. The patient has an overall activity level of 50-70% of expected. Patient is not confined to house; is unable to perform strenuous duties, but can perform light duty/desk work 3-4 hours/day, but requires rest periods.

    30: Patient has moderate to severe symptoms at rest, and severe symptoms with any exercise. Patient has an overall activity level reduced to 50% of expected; is usually confined to house. Patient is unable to perform any strenuous tasks; is able to perform 2-3 hours of desk work per day, but requires rest periods.

    20: Patient has moderate to severe symptoms at rest; is unable to perform strenuous activity. Overall, activity levels are 30-50% of expected. Patient is unable to leave house except rarely, is confined to bed most of the day, is unable to concentrate for more than 1 hour/day.

    10: Patient has severe symptoms at rest, is bedridden the majority of the time. Patient has no travel outside of house. Patient
    has marked cognitive symptoms preventing concentration.


    0: Patient has severe symptoms on a continuous basis, is bedridden constantly, and is unable to care for him/her self.
    purheart and Dee4dogs like this.

Recent Reviews

  1. ElizabethE
    ElizabethE
    4/5,
    I find I don't exactly fit into any of the categories, since not everyone's 'package' of symptoms matches any of the the exact 'packages' described here.
    Also, intended interpretation of some criteria is unclear; eg would 'desk work' include lying in bed doing research, browsing articles and conversing on forums etc online - which is surely how a lot of bedbound patients spend a lot of their time, albeit with breaks for drinks/food/different sorts of mental activity eg listening to radio, to rest some parts of the brain, or just gazing blankly into space, mentally drifting. I often spend hours online in this way, but couldn't possibly do it sitting at a desk due to OI, or meet any normal employer's demands and deadlines etc., since comprehension of read material and composing written material, like this, is extremely slow and laborious, constantly clearing the muddle in one's brain as one goes.
    Furthermore, there would certainly be some days, not necessarily predictable, when no such activity online would be tolerable. One can't just say I can definitely do 'x' number of hours using a laptop per day... I also wonder how many days a week does it assume this 'desk work' takes place - every day, or 5 days per week with 2 days off for recovery as would probably happen if one was employed?

    Having said all this, it's still a really good resource, in the absence of anything better, even if it's just to provide a jumping off point for understanding and further discussion of where someone is currently at with their illness, in terms of functionality.
  2. Dee4dogs
    Dee4dogs
    5/5,
    I've never seen anything like this before. It would be nice if Social Security was using this resource in their disability approval process. (I'm at 30.)