Performance status

In medicine (oncology and other fields), performance status is an attempt to quantify cancer patients' general well-being and activities of daily life. This measure is used to determine whether they can receive chemotherapy, whether dose adjustment is necessary, and as a measure for the required intensity of palliative care. It is also used in oncological randomized controlled trials as a measure of quality of life.

There are various scoring systems. The most generally used are the Karnofsky score and the Zubrod score, the latter being used in publications by the WHO. For children, the Lansky score is used. Another common system is the Eastern Cooperative Oncology Group (ECOG) system. Parallel scoring systems include the Global Assessment of Functioning (GAF) score, which has been incorporated as the fifth axis of the Diagnostic and Statistical Manual (DSM) of psychiatry.

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. This scoring system is named after Dr. David A. Karnofsky, who described the scale with Dr. Walter H. Abelmann, Dr. Lloyd F. Craver, and Dr. Joseph H. Burchenal in 1948. The primary purpose of its development was to allow physicians to evaluate a patient's ability to survive chemotherapy for cancer.

The Eastern Cooperative Oncology Group (ECOG) score (published by Oken et al. in 1982), also called the WHO or Zubrod score (after C. Gordon Zubrod), runs from 0 to 5, with 0 denoting perfect health and 5 death: Its advantage over the Karnofsky scale lies in its simplicity.

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