Karnofsky Performance Scale

Karnofsky Performance Scale or (KPS) was named after Dr. David A. Karnofsky (1914 – 1969), an American clinical oncologist. Karnofshy, together with Dr. Walter H. Abelmann, Dr. Lloyd F. Craver, and Dr. Joseph H. Burchenal developed the Karnofsky Performance Status Scale in 1948 in order to evaluate a patient's ability to survive chemotherapy for cancer in a more objective manner.

Karnofsky scoring
The Karnofsky score runs from 100 to 0, where 100 is "perfect" health and 0 is death. Practitioners occasionally assign performance scores in between standard intervals of 10.

100 – Normal; no complaints; no evidence of disease. 90 – Able to carry on normal activity; minor signs or symptoms of disease. 80 – Normal activity with effort; some signs or symptoms of disease. 70 – Cares for self; unable to carry on normal activity or to do active work. 60 – Requires occasional assistance, but is able to care for most of their personal needs. 50 – Requires considerable assistance and frequent medical care. 40 – Disabled; requires special care and assistance. 30 – Severely disabled; hospital admission is indicated although death not imminent. 20 – Very sick; hospital admission necessary; active supportive treatment necessary. 10 – Moribund; fatal processes progressing rapidly. 0 – Dead

Use in ME/CFS
The scale was shown to be validated in patients with chronic pain, but not specifically CFS. Beth Smith ME, Nelson HD, Haney E, et al. Diagnosis and Treatment of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Rockville (MD): Agency for Healthcare Research and Quality (US); 2014 Dec. (Evidence Reports/Technology Assessments, No. 219.) Appendix J, Standardized Measures Tables. Available from: http://www.ncbi.nlm.nih.gov/books/NBK293939/