Karnofsky performance status (KPS)
Karnofsky performance status (KPS) is a widely used scale that evaluates cancer patients' functional abilities and their capacity to perform daily activities. Developed in 1948, KPS has been adapted for various cancers and terminal illnesses, remaining relevant in contemporary medical practice. The scale ranges from 0 percent, indicating death, to 100 percent, denoting normal functioning without complaints or disease evidence. Each score corresponds to specific definitions that help assess the patient's level of independence, with lower scores indicating significant impairment and a potential need for hospital care. Scores in the 50 to 70 percent range suggest varying degrees of assistance required for daily tasks, while scores of 80 percent and above indicate greater independence. Trained clinicians typically administer the KPS by observing patients and gathering information about their symptoms and limitations. This tool not only aids in gauging the severity of illness but also assists healthcare providers in planning appropriate care, predicting patient longevity, and monitoring disease progression. However, it is important to note that KPS primarily focuses on functional impairment and does not encompass broader quality of life factors such as emotional well-being.
On this Page
Karnofsky performance status (KPS)
DEFINITION: The Karnofsky performance status (KPS) scale is a tool used to measure cancer patients’ ability to function and conduct activities of daily living. The KPS first appeared in the scientific literature in 1948 in a study of patients’ responses to palliative treatment for inoperable lung cancer and was widely adapted after that for use in other types of cancers and terminal illnesses. The KPS remains commonly used in research and clinical applications in the twenty-first century.
Description: The Karnofsky performance status scale describes functional status to compare or assess therapies. The scoring on each point ranges from 0 percent (dead) to 100 percent (normal, no complaints, no evidence of disease) in intervals that represent percentages of “normal” functioning. Each score is associated with a brief definition to aid in scoring.
Scores below 40 percent indicate significant impairment and an inability to care for oneself. The disease may be progressing, and hospital care may be needed. Scores between 50 and 70 percent indicate the inability to work with varying amounts of help needed for everyday tasks. Scores of 80 percent and above indicate the person is able to conduct daily activities without special care.
Administration and scoring: A trained interviewer or clinician determines the KPS score. The person scoring the KPS observes the patient and gathers information on the patient’s symptoms, limitations, and dependence on others. Examples of abilities and activities that the scorer might consider include independence in dressing, bathing, toileting, and mobility in and around the home. At higher levels of functioning, scores reflect the degree of effort required to carry out work and other activities or the degree to which symptoms interfere with everyday activities. At the lowest levels of functioning, scores reflect the need for acute medical care and institutional services.
Clinical use: It is helpful for health providers to know the clinical status of a patient’s disease and how much it has impaired their ability to function. Broadly, a patient’s functional status can represent the disease's overall physical and psychological toll on the ability to carry out day-to-day activities. The KPS score provides a concise summary that can help healthcare providers determine a patient’s need for hospitalization, nursing care, and other services. In several studies, the KPS has proven helpful in predicting longevity among patients with advanced disease, and a decline in the KPS score is a sensitive indicator of late-stage disease progression. The KPS primarily measures functional impairment and disability and does not necessarily reflect broader aspects of quality of life, such as emotional distress or life satisfaction.
Bibliography
Christensen, Buck. "Karnofsky Performance Status Scale." Medscape, 19 Jan. 2023, emedicine.medscape.com/article/2172510-overview. Accessed 20 June 2024.
Goldberg, Maria, et al. "Enhancing Outcomes: Neurosurgical Resection in Brain Metastasis Patients with Poor Karnofsky Performance Score-a Comprehensive Survival Analysis." Frontiers in Oncology, vol. 13, 2024, 1343500. doi.org/10.3389/fonc.2023.1343500.
Jang, Raymond W., et al. "Simple Prognostic Model for Patients with Advanced Cancer Based On Performance Status." Journal of Oncology Practice 10.5 (2014): e335–e341.
Lederman, Robert J. Tarascon Internal Medicine and Critical Care Pocket Book. 5th ed. Jones, 2013.
Leppert, Wojciech, et al. "Quality of Life Assessment in Advanced Cancer Patients Treated at Home, an Inpatient Unit, and a Day Care Center." Oncotargets & Therapy 7 (2014): 687–95.
McNair, Keara M., et al. "Translation of Karnofsky Performance Status (KPS) for Use in Inpatient Cancer Rehabilitation." PM&R, vol. 15, no. 1, 2023, pp. 65-68. doi.org/10.1002/pmrj.12741.
Schag C. C., et al. “Karnofsky Performance Status Revisited: Reliability, Validity, and Guidelines." Journal of Clinical Oncology, vol. 2, no. 3, 1984, pp. 187–93. doi:10.1200/JCO.1984.2.3.187.
Zhou, Jie, et al. "The Impact of Karnofsky Performance Status on Prognosis of Patients with Hepatocellular Carcinoma in Liver Transplantation." BMC Gastroenterology, vol. 24, no. 1, 2024, p. 85. doi.org/10.1186/s12876-024-03161-7.