Evaluation of an Activities of Daily Living Scale for Adolescents and Adults With Developmental Disabilities

Activity limitations are an important and useful dimension of disability, but there are few validated measures of activity limitations for adolescents and adults with developmental disabilities. This evaluation set out to describe the development of the Waisman Activities of Daily Living (W-ADL) Scale for adolescents and adults with developmental disabilities, and systematically evaluate its measurement properties according to an established set of criteria.

The W-ADL was administered among four longitudinally studied groups of adolescents and adults with developmental disabilities: 406 with autism; 147 with fragile-X syndrome; 169 with Down syndrome; and 292 with intellectual disability of other or unknown origin. The study found significant group differences in W-ADL scores by maternally reported level of intellectual disability (mild, moderate, severe or profound).

The research team included experienced clinicians and family members of people with developmental disabilities. The team selected and modified items from earlier ADL questionnaires and identified additional relevant activities. The W-ADL is designed to provide information about the level of performance of common daily activities of adults. Researchers adapted items to be succinct, appropriately worded and applicable to the target population.

Before each wave of data collection, the team pilot-tested items and solicited feedback from respondents on the length and appropriateness of the items. Over time, items that were nearly always concordant were collapsed into a single item (such as bathing upper and lower body). The team excluded items that were frequently unanswered or items that were especially dependent on environment. For example, the team excluded questions about public transportation or taxi use because participants frequently indicated that these items were not applicable to their situation.

The 17 items in the final version of the W-ADL (Table 1) pertain to the current or expected performance of the person when the survey was given.

Table 1. W-ADL items

1.      Making his/her own bed
2.      Doing household tasks, including picking up around the house, putting things away, light housecleaning, etc.
3.      Doing errands, including shopping in stores
4.      Doing home repairs, including simple repairs around the house, non-technical in nature; for example, changing light bulbs or repairing a loose screw
5.      Doing laundry, washing and drying
6.      Washing/bathing
7.      Grooming, brushing teeth, combing and/or brushing hair
8.      Dressing and undressing
9.      Toileting
10.   Preparing simple foods requiring no mixing or cooking, including sandwiches, cold cereal, etc.
11.   Mixing and cooking simple foods, fry eggs, make pancakes, heat food in microwave, etc.
12.   Preparing complete meal
13.   Setting and clearing table
14.   Drinking from a cup
15.   Eating from a plate
16.   Washing dishes (including using a dishwasher)
17.   Banking and managing daily finances, including keeping track of cash, checking account, paying bills, etc. (Note: if he/she can do a portion but not all circle ‘1’ with help.)

The target adult’s performance of each activity is rated on a 3-point scale: 0 = “does not do at all,” 1 = “does with help,” and 2 = “independent.” Item scores are summed to produce an overall score.

 

Discussion

This analysis supports the reliability and validity of the W-ADL in research on adolescents and adults with developmental disabilities. The 17-item W-ADL appears to be an extremely efficient and practical measure for assessing adults with relatively substantial disabilities. The W-ADL could detect group differences between subjective or categorical “levels” of intellectual disability, including between severe and profound intellectual disability. Whereas many of the study participants scored at the extreme low end of the population distribution on other measures, substantial differences within these groups emerged when using an appropriate and adult-oriented tool.

Because the majority of the participants had significant intellectual disabilities or other serious impairments, information on the level of performance equal to the “ceiling” of the scale is limited. Future work should consider items that may extend the “ceiling” of the W-ADL.

Selecting additional activities should be informed through soliciting suggestions from people with the disability (when feasible) and their family members or caregivers. A planned future study will directly interview participants about the determinants of their quality of life, and their responses will help inform the future development of the W-ADL.

Further work is needed to determine the minimum important change in scores. Because each point on the W-ADL represents partial or complete independence in a specific activity, any change in score could be perceived as important, depending on the activity and context. Additional work is also needed to develop possible inferences from W-ADL scores. This research found that the W-ADL was associated with perceived caregiving burden, parent-reported need for services, and educational and vocational attainment. These associations could form the basis for a deeper analysis of the W-ADL’s predictive and discriminative properties. For example, could a score at a certain age predict future employment or living situation? How well do scores discriminate between people that do and don’t qualify for certain services?

A major strength of this analysis is its use of some of the largest and longest-running studies of the phenotype of autism, fragile X, Down syndrome, and intellectual disability in adulthood. In addition to the W-ADL items, numerous other instruments and questionnaires were administered throughout the studies, thereby affording the opportunity to examine different aspects of validity. Another important strength is the inclusion of adults with different categorical diagnoses. While the symptomatology and etiology between fragile X, Down syndrome, autism, and intellectual disability may differ, the W-ADL performed similarly across groups in terms of measurement properties.

The W-ADL may also be useful for disability screening or large surveys, particularly in low-resource settings. Activity- or ADL-based measures have been used in disability screening and their interdisciplinary and cross-cultural relevance offer practical utility in many situations. Additional work is needed to assess whether these items are relevant in different contexts and cultures, and to consider how specific activities may be more or less essential to — or representative of — typical life situations. Here, the International Classification of Functioning, Disability and Health (ICF) would serve as a useful framework for identifying important new activities, understanding relationships between different levels of disability, and identifying environmental barriers and facilitators for the performance of activities.

Conclusions

The W-ADL exceeded the recommended threshold for each quality criterion the authors evaluated. This freely available tool (at www.waisman.wisc.edu/family/WADL) is an efficient measure of activities of daily living for surveys and epidemiological research concerning adolescents and adults with developmental disabilities.

This article is a condensed version of a research article that appeared in the January 2013 issue of Health and Disability News.. The research team included Matthew J. Maenner, PhD, Leann E. Smith, PhD, Jinkuk Hong, PhD, Renee Makuch, BS, Jan S. Greenberg, PhD and Marsha R. Mailick, PhD.