Assessment & Research

Screening of Broader Autism Phenotype Symptoms in Siblings: Support for a Distinct Model of Symptomatology.

Rankin et al. (2019) · Journal of autism and developmental disorders 2019
★ The Verdict

Count CSBQ items, not severity scores, when spotting BAP in siblings.

✓ Read this if BCBAs who assess siblings of children with ASD in clinic or research settings.
✗ Skip if Practitioners only working with adults or single-child families.

01Research in Context

01

What this study did

The team looked at the Children’s Social Behavior Questionnaire (CSBQ) in two groups. One group had autism. The other group were their brothers and sisters.

They wanted to know if counting how many items parents tick off works better than adding up severity scores.

02

What they found

The CSBQ kept the same five-factor shape in both kids with autism and in their siblings.

The thing that set siblings apart was simply how many items parents said “yes” to, not how strong each trait was.

03

How this fits with other research

Lancioni et al. (2000) built the CSBQ and showed it separates autism from other groups. Pitchford et al. (2019) now show the same form holds for siblings, so you can keep using the tool across the whole family.

Bao et al. (2017) found parents and siblings rarely agree on who is “at-risk.” The new paper adds a fix: look at item count, not severity, to lower the noise.

Muller et al. (2022) warn that parents who have BAP traits over-rate symptoms. Counting items instead of weighting severity may reduce this parent-bias effect.

04

Why it matters

If you screen siblings for the broader autism phenotype, ignore the big severity numbers. Just count how many CSBQ boxes the parent checks. This quick shift can give you a clearer yes-or-no signal and keeps you from chasing mild but highly scored items that do not separate siblings from typical kids.

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Open the CSBQ, tally the checked items, and use that raw count as your first red-flag for BAP.

02At a glance

Intervention
not applicable
Design
other
Sample size
442
Population
autism spectrum disorder, neurotypical
Finding
not reported

03Original abstract

Research on siblings of youth with autism spectrum disorder (ASD) suggests that some phenotypic presentation, known as the broader autism phenotype (BAP), is common among siblings without an ASD diagnosis (e.g., Ruzich et al. in Autism Res 9(6):658-665, 2016). Whereas the symptoms that underlie both ASD and the BAP share commonality, the structure of these symptoms in youth with ASD and their siblings may differ. The current study assessed whether differences arise in the factor structure of the Children's Social Behavior Questionnaire (CSBQ) between youth with ASD and their siblings in a sample of 221 sibling dyads. Results suggest similar factor structures for ASD and BAP; however, number of symptoms endorsed, as opposed to the degree of severity, may better differentiate BAP.

Journal of autism and developmental disorders, 2019 · doi:10.1007/s10803-019-04157-z