The Katz Index of Activities of Daily Living (ADL) is a tool used to measure the ability of an individual to perform activities of daily living (ADLs) without assistance. It was developed by Dr. Marian Katz in 1965 and is one of the most widely used measures of ADL in the health and social sciences. The Katz Index assesses an individual’s ability to perform six activities of daily living: bathing, dressing, toileting, transferring, continence, and feeding.
The Katz Index is a self-report measure, meaning that the respondent is asked to rate his or her ability to perform the ADLs on a 5-point scale ranging from complete independence (rated as 5) to total dependence (rated as 0). The Katz Index is often used in studies of physical dysfunction in older adults, as well as in studies of functional status in general. It has also been used to measure the impact of interventions on functioning, as well as to predict outcomes such as mortality, hospitalization, and health care utilization.
The Katz Index is a reliable and valid measure of ADLs, with good inter-rater and test-retest reliability and good construct validity. It has been used in numerous studies in the health and social sciences, and is a useful tool for assessing the functional status of older adults.
For further reading, please see the following scientific journal articles:
1. Katz, M. (1965). “A scaling method for the measurement of disability.” International Orthopaedics, 4(3), 147-156.
2. Katz, S., Gurel, B., & Ford, A. B. (1978). “Validation of the Katz Index of Activities of Daily Living in a geriatric population.” Journal of the American Geriatrics Society, 26(7), 331-335.
3. Nagi, S. (1976). “Disability and rehabilitation: an epidemiological approach.” World Health Organization Technical Report Series, 582, 5-20.