Functional status is an individual's ability to perform normal daily activities required to meet basic needs, fulfill usual roles, and maintain health and well-being. Decline in functional status is measured by an individual's loss of independence in activities of daily living (ADLs) over a period of time.

The following is a selection of tools that can be used to rate the ability of patients to maintain their independence in the context of their daily life and encompass dimensions of physical, emotional, and cognitive state.

ECOG Performance Status
A tool for doctors and researchers to assess how a patient's disease is progressing, how the disease affects the daily living abilities of the patient, and how to determine appropriate treatment and prognosis.

Edmonton Functional Assessment Tool (EFAT)
A tool to evaluate functional performance of patients with advanced cancer over time and to document the degrees of functional performance of patients throughout the terminal phase.

Karnofsky Performance Scale
Commonly used for assessing terminally ill patients, often used to determine appropriateness of hospice referral.

Katz Index of Independence in Activities of Daily Living
Assesses the ability of patients to conduct activities of daily living.

Palliative Performance Scale version 2 (PPSv2)
Measures the functional status of a patient and assigns a Palliative Performance Value; serves as a communication tool for quickly describing a patient's current functional level.