Katz Index of Activities of Daily Living (Katz Index of ADL)

BioPsychoSocial Assessment Tools for the Elderly - Assessment Summary Sheet

Test: Katz Index of Activities of Daily Living (Katz Index of ADL)

Year: 1959

Domain: Biological

Assessment Tool Category: Physical Functioning/ADLs

Test Category (Bio, Psycho or Social): Biological

Variations/Translations: None

Setting: Clinical

Method of Delivery: Completed by a health professional

Description: The Index of ADL is used to measure the physical functioning of chronically ill patients and the elderly. It can be used to describe the severity of chronic illness, to evaluate the treatment effectiveness and to predict the course of illness. It assesses independence in six functions: bathing, dressing, toileting, transfer from bed to chair, continence and feeding. The rater rates each activity based on observation and interview. Observations of transfer, locomotion, and communication are conducted.

Scoring/Interpretation: Each activity is rated on a three-point scale of independence and the most dependent degree of performance during a two week period is recorded (McDowell & Newell, 1996). Using a guideline, scoring involves translating the three points into “dependent/independent” rankings before summarizing the overall performance on an eight-point scale. Simplified scoring involving counting the number of activities in which the participant is dependent and assigning a number from 0 to 6 (0 being independence in all functions while 6 is dependence in all functions).

Time to Administer: 10 minutes (McDowell & Newell, 1996).

Availability: Found in Katz et al. (1963).

Software: None

Website: None

Quantitative/Qualitative: Quantitative

Validity (Quantitative): The scores of the Index showed a correlation of 0.5 with a mobility scale, and 0.39 with a house confinement scale (Katz, Ford & Moskowitz, et al., 1963). The Index of ADL is not resistant to the floor effect seeing by all other ADL scales: it is insensitive to variations in low levels of disability (McDowell & Newell, 1996).

Reliability (Quantitative): ): Inter-rater reliability has been assessed and it has been found that inter-observer variability occurred 1/20 evaluations or less (Katz et al., 1963).


Katz, S., Ford, A.B., Moskowitz, R.W., et al. (1963). Studies of illness in the aged. The Index of ADL: a standardized measure of biological and psychosocial function. JAMA, 185, 914-919.

McDowell, I. & Newell, C. (1996). Measuring Health: A Guide to Rating Scales and Questionnaires. (2nd ed.). New York: Oxford University Press. Pp. 63-67.

Comments: None.