The assessment of adaptive behavior is complex. One must consider not only general competencies across relevant domains but also the level, quality, and fluency of those behaviors. In addition, there is the issue of the ability to perform behaviors (i.e., can do) versus the actual performance of those skills (i.e., does do). In order for the assessment to be clinically and scientifically meaningful, it is important that the assessor be sufficiently trained in using and interpreting appropriate instruments. A high level of training is necessary in order to capture and distinguish the level, quality, and pattern of adaptive behavior displayed by a given subject, as viewed by the eyes of the respondent (parent, teacher, or caregiver).
The frequency of performance can be classified along a dimension from “never” to “usually or always.” The number of choice points varies by specific instrument or by the variation in the clinical interpretation of the assessor when a formal assessment instrument is not used. The quality of performance may be somewhat more subjective, but a key feature is the appropriateness of a given level of adaptive behavior performance. For example, one needs to distinguish between an individual’s deficit in a specific adaptive behavior skill, as opposed to a deficit in a larger domain.
There are a number of ways to assess the level, quality, and pattern of adaptive functioning, each with its own strengths and weaknesses. These include clinical assessment by interview methods (unstructured, structured, semistructured, direct observation), usually with the aid of clinical instruments that are completed by the evaluator during the interview, and the use of checklists that are completed either by an observer or by the individual being assessed.