An individual’s ability to live independently is often determined by that person’s capacity for self-care and ability to engage in various activities of daily living (ADLs). Basic or self-care ADLs include such everyday behaviors as attention to hygiene, bathing, dressing, feeding, and toileting. Complex or instrumental activities of daily living (IADLs) include such tasks as cooking and meal preparation, medication administration, financial management, use of communication devices (e.g., telephone), and use of transportation (e.g., driving a vehicle). In older individuals, increasing frailty or declines in cognitive ability are heralded by declines in IADLs followed by declines or disruptions in basic ADLs. Consequently, health care providers routinely evaluate the older individual’s level of independence in, versus support needed across, a range of IADLs and ADLs.
ADL functioning may be assessed in three ways: self-report, informant (caregiver) report, or performance of actual ADL tasks. The most common method of ADL assessment is self-report or informant report through informal interview. The individual or primary caregiver (e.g., spouse, adult child) is asked whether the individual requires assistance in any of a range of ADL tasks. Formal self-report questionnaires obtain this information in a standardized way. Lawton and Brody (1969), for example, developed an ADL questionnaire that can be completed either by the individual or by an informant. The questionnaire includes a range of both ADL and IADL behaviors, and the respondent rates each item according to whether he or she is entirely independent in the task (2 points), requires assistance to complete the tasks (1 point), or is entirely dependent on someone else for task completion (0 points). The questionnaire is scored by summing the item responses, with lower scores reflecting greater dependence and need for assistance in IADLs and ADLs. The Older Americans Resources and Services Instrument (OARS), developed for community-based assessment of ADLs in research studies, is similar to the Lawton and Brody measure, although it is an interviewer-administered questionnaire.
Although the self and interviewer-administered questionnaire method of assessing ADLs is cost-effective and takes little time to administer, the accuracy of this method is dependent on the respondent’s honest appraisal or awareness of the individual’s true functioning. Research suggests that individuals providing self-report of their own ADL abilities tend to overestimate their functioning, whereas caregivers tend to underestimate their family members’ functioning. As such, agreement between self-reports and informant reports may be low, particularly for the more complex IADLs. Disagreements may stem from individuals’ overestimates of their own abilities because of lack of awareness of declines or attempts to minimize ADL deficiencies for fear of losing independence. Alternatively, the discrepancies may reflect misestimates by caregivers who have insufficient knowledge of the individual’s functioning across the various ADL tasks or from feeling burdened by the care that they already provide to their family members.
Direct performance-based assessment is an alternative method for assessing ADLs that minimizes any biases or inaccuracies in self-report or caregiver report. In this approach, the individual is given a variety of tasks, and his or her performance is rated on each task based on predetermined criteria. Tasks can include cooking (e.g., making a grilled cheese sandwich, heating up soup), money management (e.g., entering a transaction into a checkbook), and telephone use (e.g., making a phone call and asking for information). Research suggests that performance-based ADL measures are more accurate than self-reports or caregiver reports, and they may be better at determining the individual’s level of care needs. The performance-based approach is typically used by occupational therapists in inpatient or rehabilitation settings because these settings provide sufficient time and space to make the detailed observations necessary to plan for the individual’s needs. However, few of the performance-based ADL measures used in these settings have been developed for commercial use, and therefore they are not widely available. In addition, this method may be neither suitable nor cost-effective for use in outpatient settings (e.g., a general physician’s offices) because of the space (e.g., kitchen setup for cooking tasks) and equipment requirements.
- Lawton, P., & Brody, E. M. (1969). Assessment of older people: Self-maintaining and instrumental activities of daily living. Gerontologist, 9, 179–186.
- Older Americans Resources and Services, Duke University. (1975, revised 1988). The OARS Multidimensional Functional Assessment Questionnaire. Durham, NC: Duke University