Objectives: This study aimed to compare associations between parental depression and measures of autistic symptoms in preschoolers with ASD. Hypotheses: 1) Parental depression symptoms will be more strongly associated with parent-report questionnaire of offspring ASD symptoms than with scores on parent interview, and least strongly with researcher observation; 2) Parental depression symptoms will be positively associated with measurement error on the parent-report questionnaire of offspring ASD symptoms.
Methods: Time 1 data were obtained from a longitudinal study of preschoolers aged 2-4 newly diagnosed with ASD. Participants who completed ADOS Module 1 and for whom data were available for all relevant measures were included (n=224). Child ASD symptoms were assessed using the Social Responsiveness Scale (SRS), a parent-report questionnaire, the Autism Diagnostic Interview-Revised (ADI-R), a semi-structured parent interview and the Autism Diagnostic Observation Schedule, a semi-structured assessment. Parents also completed the Symptoms Checklist-90.
Results: Two sets of structural equation models were developed. In Model 1: parent depression, SRS, ADI-R and ADOS were each represented by a latent variable. The gradient of strength of association between parental depression and each measure was assessed by comparing the size of the regression weight for paths between parent depression and each measure, and the changes in goodness of fit when the paths were constrained to equal each other. Model 2 comprised a latent variable representing parental depression and another one representing ASD symptoms with SRS, ADI-R and ADOS totals as indicators. Parental depression was correlated with the error term for the SRS as well as with the child ASD symptom latent variable. Model 1 demonstrated a gradient of strength of association; the regression coefficient for the path from parent depression to the SRS variable (β=0.35; p < 0.001) was twice as large as that to the ADI-R (β = 0.15, p>0.05) and the path from depression to ADOS was not significantly different from zero (β = 0.08; n.s.). The model demonstrated an excellent fit to the data (CFI = 0.95, RMSEA = 0.06; fit worsened significantly when all paths were constrained to equal each other (Δχ2=17.2(2), p < 0.01). In Model 2, the correlation between parental depression and the error term for the SRS (r= 0.29, p < 0.001) was statistically significant and larger than that between parental depression and child ASD symptoms (r=0.16,p < 0.07); fit worsened significantly when it was constrained to equal zero (Δχ2=17.1 (1), p < 0.01).
Conclusions: Parental depression may significantly influence reporting of severity of autistic symptoms in their children. This study reinforces the importance of obtaining multiple-informant reports of ASD symptoms.