To conduct clinical trials for the treatment of cancer in a consistent manner across many participating hospitals, cancer centers, and clinics requires the use of standard criteria for measuring how the disease impacts a patient’s daily living abilities (known to physicians and researchers as a patient’s performance status). The ECOG Scale of Performance Status is one such measurement. It describes a patient’s level of functioning in terms of their ability to care for themself, daily activity, and physical ability (walking, working, etc.).
Researchers worldwide take the ECOG Performance Status into consideration when planning trials to study a new treatment method. This numbering scale is one way to define the population of patients to be studied in the trial, so that it can be uniformly reproduced among physicians who enroll patients. It is also a way for physicians to track changes in a patient’s level of functioning as a result of treatment during the trial.
The scale was developed by the Eastern Cooperative Oncology Group (ECOG), now part of the ECOG-ACRIN Cancer Research Group, and published in 1982. It circulates in the public domain and is therefore available for public use. It is displayed below both for future reference and to spur further standardization among researchers who design and evaluate cancer clinical research.
ECOG Performance Status
Developed by the Eastern Cooperative Oncology Group, Robert L. Comis, MD, Group Chair.*
|GRADE||ECOG PERFORMANCE STATUS|
|0||Fully active, able to carry on all pre-disease performance without restriction|
|1||Restricted in physically strenuous activity but ambulatory and able to carry out work of a light or sedentary nature, e.g., light house work, office work|
|2||Ambulatory and capable of all selfcare but unable to carry out any work activities; up and about more than 50% of waking hours|
|3||Capable of only limited selfcare; confined to bed or chair more than 50% of waking hours|
|4||Completely disabled; cannot carry on any selfcare; totally confined to bed or chair|
*Oken M, Creech R, Tormey D, et al. Toxicity and response criteria of the Eastern Cooperative Oncology Group. Am J Clin Oncol. 1982;5:649-655.
The ECOG Performance Status and the Karnofsky Performance Status are two widely used methods to assess the functional status of a patient. Both scales have been in the public domain for many years as ways to classify a patient according to their functional impairment, compare the effectiveness of therapies, and assess the prognosis of a patient. The Karnofsky index, between 100 and 0, was introduced in a textbook in 1949.* Key elements of the ECOG scale first appeared in the medical literature in 1960.**
There are several ways to map the two scales. The table below displays one commonly used comparison.
|ECOG PERFORMANCE STATUS||KARNOFSKY PERFORMANCE STATUS|
|0—Fully active, able to carry on all pre-disease performance without restriction||100—Normal, no complaints; no evidence of disease
90—Able to carry on normal activity; minor signs or symptoms of disease
|1—Restricted in physically strenuous activity but ambulatory and able to carry out work of a light or sedentary nature, e.g., light house work, office work||80—Normal activity with effort, some signs or symptoms of disease
70—Cares for self but unable to carry on normal activity or to do active work
|2—Ambulatory and capable of all selfcare but unable to carry out any work activities; up and about more than 50% of waking hours||60—Requires occasional assistance but is able to care for most of personal needs
50—Requires considerable assistance and frequent medical care
|3—Capable of only limited selfcare; confined to bed or chair more than 50% of waking hours||40—Disabled; requires special care and assistance
30—Severely disabled; hospitalization is indicated although death not imminent
|4—Completely disabled; cannot carry on any selfcare; totally confined to bed or chair||20—Very ill; hospitalization and active supportive care necessary
*Karnofsky D, Burchenal J, The clinical evaluation of chemotherapeutic agents in cancer. In: MacLeod C, ed. Evaluation of Chemotherapeutic Agents. New York, NY: Columbia University Press; 1949:191–205.
**Zubrod C, et al. Appraisal of methods for the study of chemotherapy in man: Comparative therapeutic trial of nitrogen mustard and thiophosphoramide. Journal of Chronic Diseases; 1960:11:7-33.