The broad autism phenotype questionnaire.

Emerson et al. (2007) built a 36-item parent questionnaire called the BAPQ. It asks moms and dads how well short statements describe them. Sample item: "I find it hard to work out people’s intentions."

The team gave the form to the adults. Half were parents of autistic kids. Half were parents of neurotypical kids. They wanted a quick screen for the broad autism phenotype.

The BAPQ caught the broad autism phenotype with a large share sensitivity and a large share specificity. That means four out of five parents who truly carried subtle autism-like traits scored positive. Four out of five parents without the traits scored negative.

The form takes five minutes to finish. It needs no trained interviewer. Internal consistency was high (α = .93).

Drijver et al. (2025) also built a new tool, the DIAB, for adults with ID. Both papers show the same recipe: write short items, test large groups, report reliability and validity. The BAPQ does this for neurotypical parents; the DIAB does it for adults with moderate–profound ID.

Laycock et al. (2014) looked at high autistic traits in neurotypical adults, too. They linked traits to slower visual perception. Emerson et al. (2007) give you the quick trait score you need before running such lab tasks.

Iversen et al. (2021) meta-analyzed executive-function links to repetitive behaviors. Many of their pooled studies used the BAPQ to pick high-trait adults. The 2021 paper therefore depends on the 2007 scale, showing the BAPQ has become a standard gatekeeper.

If you run parent training or sibling studies, start with the BAPQ. It flags adults who may need extra social prompts or clear schedules. A high score tells you to write plain instructions, use visual aids, and check for literal understanding. The form is free and fast—drop it into your intake packet today.