Differential Item Functioning Based on Autism Features, IQ, and Age on the Screen for Child Anxiety Related Disorders (SCARED) Among Youth on the Autism Spectrum

Abstract

Anxiety commonly occurs among youth on the autism spectrum, yet measurement of anxiety in this population is complicated by a number of factors, including potentially overlapping symptomatology, the child's intellectual functioning, and changes in anxiety across development. Moreover, few studies have examined the psychometric properties of anxiety measures in this population, and no study to date has tested whether there are systematic differences in the measurement of anxiety, or differential item functioning (DIF), across the high degree of heterogeneity and the developmental course of autism. To test this possibility, data were combined across multiple studies using the National Database for Autism Research, an NIH‐funded data repository. Parent‐report on the Screen for Child Anxiety Related Disorders (SCARED) and Social Communication Questionnaire (SCQ) were used as measures of anxiety and autism features, respectively. A confirmatory factor analysis indicated good fit of the literature standard five‐factor structure. Moderated nonlinear factor analysis (MNLFA) revealed multiple items with intercept and loading DIF based on level of autism features, IQ, and age, especially for items related to social behavior. Therefore, although the measure's factor structure is consistent with that found in the general population, the SCARED may not capture differences in anxiety equivalently for all children on the spectrum and across their development. Clinicians and researchers need to be especially vigilant in measuring anxiety symptoms in children with autism by removing items flagged for DIF from the SCARED and/or by using multiple measures and informants. Lay Abstract Autistic youth often experience clinical levels of anxiety. Many tools used to measure anxiety were developed for the general population, but not for use with autistic youth. This study found that the Screen for Child Anxiety Related Disorders (SCARED) measures the same five dimensions of anxiety as in the general population. Parents, however, may respond differently to questions on the SCARED based on their child's autism features, intellectual functioning, and age, which impacts our ability to accurately measure anxiety among autistic youth.

Differentiation of autism spectrum disorder and mood or anxiety disorder

“…In addition, there may be confounders that were not considered in our analyses like the child’s intellectual as well as adaptive functioning, comorbidities, and changes in anxiety across development. There is evidence that these factors affect the development and intensity of MAD symptomatology also in individuals with ASD ( Ben-Itzchak et al, 2020 ; Schiltz & Magnus, 2021 ). Therefore, future investigations should include samples comprising a broader range of thoroughly surveyed data on symptomatology and should also consider confounders like age and IQ, allow for gender differentiations as well as for other potential confounders such as comorbidity or other medical conditions.…”

Transdermal Electrical Neuromodulation for Anxiety and Sleep Problems in High-Functioning Autism Spectrum Disorder: Feasibility and Preliminary Findings

“…The results suggest TEN treatment could have a cumulative effect on improving anxiety in ASD. Although the questionnaire demonstrated a positive response to treatment, questionnaires are subjective, and studies have shown that they do not capture anxiety differences equivalently for all individuals with ASD [70]. More objective measurements of anxiety would improve future studies.…”

Measurement matters: A commentary on the state of the science on patient reported outcome measures (PROMs) in autism research

“…That is, it may be difficult to distinguish between an instrument's target construct (e.g., anxiety) and autistic traits or related behaviors that could be but are not necessarily related to that construct (e.g., repetitive behavior or fidgeting). For example, measures intended to capture autism traits may be elevated among children with more externalizing behavior and lower language and cognitive skills (Hus et al, 2013) and that responses on measures of anxiety may be impacted by autism characteristics (Schiltz & Magnus, 2021). As another example, an item on a sensory reactivity questionnaire about avoiding noisy parties may be influenced by the respondent's social motivation or social anxiety.…”

“…Others have used a community based participatory research approach with autistic adults to adapt existing instruments for use with autistic participants (Nicolaidis et al, 2020). Other approaches include the application of methods such as item response theory (IRT), structural equation modeling, and network analysis, and even more standard approaches such as test–retest and convergent validity to answer substantive empirical questions about the psychometric properties of both newly‐created and existing PROMs in the autistic population (e.g., Frazier et al, 2022; Mazefsky, Yu, et al, 2018; Schiltz et al, 2019; Schiltz & Magnus, 2020, 2021; Uljarević et al, 2022; Williams et al, 2021; Williams, Cascio, & Woynaroski, 2023). Still others have begun to incorporate PROMs into routine clinical practice, and the first systems of measurement‐based care (Lewis et al, 2018) were recently described within autism research (McFayden et al, 2021; Schwartzman et al, 2023).…”