Congruence Between Parental Report and Standardized Assessment of Cognitive and Developmental Functioning Among Children with ASD

Background: Parental perception of child functioning undoubtedly influences whether children with autism spectrum disorders (ASD) receive appropriate diagnoses. Parental report is an extremely valuable, important data source when evaluating symptoms of ASD. Yet formal assessment of a child’s cognitive functioning is also important in the ASD-diagnostic process, as it provides context for a child’s abilities; however, it is not clear how often standardized IQ testing is performed as part of the ASD evaluation. Many professionals may rely on caregiver report as their primary data source for this information, but parents may not always accurately perceive or estimate their children’s level of functioning, particularly functioning in cognitive domains. For example, Geiger et al. (2002) noted that parents of children with ASD increasingly overestimated intelligence as their children’s intelligence decreased. A better understanding of (a) how parents of children with ASD perceive their children’s cognitive/developmental functioning and (b) what is being communicated to parents about their children’s cognitive levels is warranted.  

Objectives: To (a) explore parents’ perceptions of cognitive and developmental functioning among their children with ASD; (b) assess the congruence between parental report and standardized assessment of children’s functioning; and (c) determine whether evidence of ID, per cognitive-test results, was associated with families ever being told that their children met criteria for ID, mental retardation (MR), and/or global developmental delay (GDD).

Methods: Data were collected from families who simultaneously participated in the Simons Simplex Collection (SSC) at the Houston, TX, site. There were 181 probands with ASD (M age = 8.5 years, SD = 3.2; 85.6% male; 72.9% white; 59.2% of mothers had a bachelor’s degree or completed graduate school); all received current cognitive testing with either the Mullen Scales of Early Learning  (Mullen) or the Differential Ability Scales-III (DAS-II). All families completed the authors’ Cognitive and Developmental Functioning Questionnaire (CDFQ).

Results: Parental age-equivalent estimates of their children’s social, language, and overall developmental functioning per the CDFQ were 5.3 years, 6.6 years, and 6 years, respectively. Compared to children’s full-scale mental ages per cognitive assessment, 22.8% of parents overestimated and 62.9% underestimated their child’s overall developmental functioning; 71.3% of these estimates were outside a 6-month window of accuracy, while 57.5% were outside a 12-month window of accuracy. Fifty-five children (30.4%) met criteria for ID, defined as verbal and nonverbal IQ scores ≤70, and 37% were previously told their children met criteria for MR/ID and/or GDD. In 28.3% of cases, the child did not currently meet criteria for ID but the family had been told that he/she had ID/MR/GDD; for 38.9%, the child did meet criteria for ID but the family had never been told, χ² = 16.898, p < .0001.

Conclusions: Parents’ ratings of their children’s developmental functioning were generally discrepant with objective, standardized measures; more than half of parents over- or underestimated their child’s functioning by ≥ one year. Many parents further reported that professionals either are not communicating ID diagnoses when they are warranted or do communicate them when they are not. Implications and additional findings will be discussed.