Abstract:
This study sought to compare the results of the Motivation Assessment Scale
(MAS; Durand & Crimmins, 1988), Questions About Behavior Function Scale (QABF;
Matson & Vollmer, 1996) and Functional Analysis Screening Tool (FAST; Iwata &
Deleon, 1996), when completed by parent informants in a sample of children and youth
with autism spectrum disorders (ASD) who display challenging behaviour. Results
indicated that there was low agreement between the functional hypotheses derived from
each of three measures. In addition, correlations between functionally analogous scales
were substantially lower than expected, while correlations between non-analogous
subscales were stronger than anticipated. As indicated by this study, clinicians choosing
to use FBA questionnaires to assess behavioural function, may not obtain accurate
functional hypotheses, potentially resulting in ineffective intervention plans. The current
study underscores the caution that must be taken when asking parents to complete these
questionnaires to determine the function(s) of challenging behaviour for children/youth
with ASD.
