The Q-CHAT (Quantitative CHecklist for Autism in Toddlers): a normally distributed quantitative measure of autistic traits at 18-24 months of age: preliminary report.

The team built a 25-item parent form called the Q-CHAT. It asks about toddler play, eye contact, routines, and sounds.

They gave it to 754 moms of 18- to 24-month-olds. Half had an older child with autism. Half were unselected families.

Toddlers with an autistic sibling scored much higher. The gap was large and clear.

Parents filled it out twice, two weeks apart. Scores stayed steady (ICC 0.82).

Hirota et al. (2018) looked at every ASD screener for age 4 and up. They found only AQ, SCQ, and SRS have solid backup. The Q-CHAT is for younger kids, so it fills the toddler gap.

Smith et al. (1994) built the 86-item Adolescent Behavior Checklist for teens with ID. Both studies show short forms can work if items are sharp.

Oliver et al. (2002) reshaped the DBC into five clean factors for kids with ID. Like them, Carrie et al. kept the Q-CHAT short and clear so parents finish it fast.

You can hand the Q-CHAT to parents while they wait. It takes five minutes, needs no toys, and gives a number you can track over time. If the score is high, you can start early teaching right away instead of waiting for a full diagnosis.