In the field of aging, disability is measured by judging how a person performs Activities of Daily Living (ADLs) or Instrumental Activities of Daily Living (IADLs). ADLs include very basic activities like eating, toileting, bathing, transferring in and out of bed, and walking (Katz, Ford, Moskowitz, Jackson and Jaffee, 1963). IADLs include additional activities needed to get along in the world such as shopping, taking medications, using the phone, and other activities. (Lawton and Brody, 1969.) People may be disabled if they do not have the cognitive ability to perform functions without supervision or assistance. Broader definitions of disability may.
