The Short Quantitative Checklist for Autism in Toddlers (Q-CHAT-10) As an Early “Red Flag” Screen for Autism Spectrum Disorder: A High-Risk Sibling Cohort Study
Objectives: The objective of this study was to examine the classification properties of the short Quantitative Checklist for Autism in Toddlers (Q-CHAT-10) as a rapid screen for ASD in a high-risk (HR) sibling population.
Methods: Participants were drawn from an ongoing longitudinal study of early development of ASD, and included 90 high-risk (HR) infants with an older sibling with ASD. For the purpose of evaluating the Q-CHAT-10, the group was further stratified into three groups: (1) HR toddlers who received an ASD diagnosis at 36 months (HR-ASD; n=19); (2) HR toddlers who meet the criteria for the broader autism phenotype (HR-broader autism phenotype (HR-BAP); n=31) and; (3) HR toddlers that do not meet the criteria for the broader autism phenotype (HR-typically developing (HR-TD); n=40). Criteria for BAP were: (1) does not meet criteria for an ASD diagnosis; (2) two or more Mullen subtests at ≥ 1.5 standard deviations (SD) below the mean; and/or (2) one or more Mullen subtests at ≥ 2 SD below the mean; and/or (4) ADOS ≥ 3. Parent-Report Questionnaire: The Q-CHAT-10 is a 10-item questionnaire shortened from the Q-CHAT that assesses a broad range of ASD symptomology. Primary caregivers of HR toddlers completed the Q-CHAT-10 at 18 and 24 months. Statistical Analyses: Performance on the Q-CHAT-10 was compared between groups (HR-ASD, HR-BAP, HR-TD) at 18 and 24 months using two one-way ANOVAs. Group effects were explored using Benjamini & Hochberg (1995) corrections for multiple comparisons. To assess predictive ability, the sensitivity and specificity of 18- and 24-month Q-CHAT-10 scores were examined relative to the 36-month ASD diagnoses, at an individual level using the suggested cut-point of 3 (Allison et al., 2012).
Results: Higher total score on the Q-CHAT-10 differentiated the HR-ASD group from HR-BAP and HR-TD groups at both 18 (q≤0.009) and 24 months of age (q≤0.001), indicating greater frequency of ASD symptoms at these time points. Estimates of sensitivity and specificity of the Q-CHAT-10 were 0.58 and 0.72 at 18 months, and 0.59 and 0.84 at 24 months, respectively.
Conclusions: While the Q-CHAT-10 was able to distinguish groups of children with ASD from other HR toddlers who are typically developing or who exhibit the broader autism phenotype, individual classification by the Q-CHAT-10 for ASD versus not ASD was relatively poor in this limited sample. Thus, while the Q-CHAT-10 was able to identify group differences, individual classification was not sufficient to support screening in this HR sibling cohort.