Many adaptive behavior scales contain assessments of problem or maladaptive behavior, but relationships between domains of adaptive and maladaptive behavior are generally low, with correlations tending to be below .25 (and a tendency to be higher in samples of persons with severe or profound retardation—Harrison, 1987). Division 33 makes it clear that the presence of clinically significant maladaptive behavior does not meet the criterion of significant limitations in adaptive functioning (Jacobson & Mulick, 1996). Hill (1999) also emphasized that behaviors that interfere with a person’s daily activities, or with the activities of those around him or her, should be considered maladaptive behavior, not the lack of adaptive behavior. Refusal to perform a task that a person is capable of doing is also a reflection of problem behavior and should not be considered in relation to adaptive behavior. The classroom form of the Vineland Adaptive Behavior Scales (Sparrow & Cicchetti, 1985) does not include a section on maladaptive behavior, which also suggests that these authors viewed measures of problem behavior as irrelevant to diagnosis or eligibility. Greenspan (1999) also has argued for many years that the presence of maladaptive behavior, or mental illness, is irrelevant for the purpose of diagnosing of mental retardation.
If it is assumed that maladaptive behavior ratings should not contribute to diagnostic decisions about adaptive functioning, then problems in their measurement need not affect this process. However, because several adaptive behavior scales contain maladaptive components, it is worth noting important challenges to reliable measurement. Specifically, several roadblocks to meaningful ratings of maladaptive behavior were noted after publication of the original AAMD Adaptive Behavior Scales (ABS). Scales developed subsequently improved on the simple rating format found in the ABS, which contained a finite list of problem behaviors rated according to the frequency of occurrence. These improvements notwithstanding, the complexity of balancing frequency and severity of problem behavior occurrence will continue to pose problems of score interpretation.