ECOG Performance Status

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.*

*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.

Comparing the ECOG Performance Status to the Karnofsky Performance Status

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.

*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.