Assessing the Convergence of Self-Report and Informant Measures for Adults with Autism Spectrum Disorder

Background: Given the rapidly growing population of intellectually capable autistic adults, self-report measures are increasingly utilized for assessment of current functioning and treatment planning. However, there has been little research examining the utility of self-report measures or the convergence of self- and informant-report in this population. Insight into areas in which adults and caregivers are most likely to agree and disagree can help shape future assessment protocols, and can guide decisions regarding if and when multiple informants should be consulted in making diagnoses and treatment recommendations.

Objectives: Caregiver and adult self-report responses were used to examine the convergence of reporters on measures of symptom severity, daily living skills, and quality of life, as well as the extent to which each reporter’s responses were predictive of employment and independent living outcomes.

Methods: Forty pairs of autistic adults with average to above average intellectual functioning (80% male; age range: 23.83 - 47.84; M=33.18 years; childhood IQ ≥ 85) and their caregivers independently completed the Social Responsiveness Scale, 2^nd Edition: Adult Form (SRS-A), Quality of Life Questionnaire (QoL-Q), and Waisman Activities of Daily Living Scale (W-ADL). Responses on these measures were analyzed for inter-rater correlation, discrepancy size, and predictive power of objective living and employment outcomes.

Results:

Adult and caregiver responses were significantly positively correlated on all measures (r’s on the SRS-A, W-ADL, and QoL-Q=.50, .75, and .78, respectively). There was no significant difference between the mean caregiver- (M=61.97) and self-report (M=60.26) t-scores on the SRS-A (t[37]=-.95, p=.25, d=.15). On the W-ADL, caregivers reported that adults demonstrated significantly fewer (M=28.87) daily living skills than adults reported (M=30.00; t[37]=2.36, p=.023, d=.38). There was also a significant difference between caregiver- and self-report scores on the Satisfaction subdomain of the QoL-Q, with caregivers reporting significantly lower satisfaction ratings for the adults with ASD (M=20.55) than adults reported for themselves (M=22.43; t[39]=2.96, p=.002, d=.55).

Finally, hierarchical logistic regression analyses indicated that the combination of self-report and caregiver-report on all measures better predicted current independent living (χ²=8.50, p=.04) and employment status (χ²=8.99, p=.03) than did any individual reporter.

Conclusions: Taken together, the present study demonstrates that, overall, intellectually capable autistic adults can serve as reliable and accurate reporters of their own symptoms. These findings contrast with previous research suggesting that poor social insight may limit the validity of self-report for this particular population (e.g., Bishop & Seltzer, 2012). Recognizing the utility of self-report in this capacity can help to shape treatment planning, as well as provide a means of measuring intervention effectiveness in research contexts. However, adults tended to report fewer difficulties with daily living skills than caregivers reported, and predictive power of independent living and employment outcomes was highest when including both caregiver and self-report perspectives. This indicates that a multi-informant approach is likely to provide the most comprehensive information about service needs.