Comparing spoken language treatments for minimally verbal preschoolers with autism spectrum disorders.

Rhea and her team asked: Do discrete-trial drills or naturalistic play work better for preschoolers who speak fewer than 10 words?

They randomly placed 48 minimally verbal children with autism into one of two rooms. One room ran short, adult-led trials with toys and treats. The other room let the child pick toys while adults followed the child’s lead and talked.

Both groups got 12 weeks of daily 30-minute lessons. The team counted new spoken words every week.

After three months, both groups gained about the same number of new words. The style of teaching did not matter on average.

But two child traits changed the picture. Kids with very low receptive language learned more words in the drill room. Kids who already showed joint-attention skills learned just as well in the play room.

Tiede et al. (2019) and Han et al. (2025) both pooled many studies and found the same bottom line: naturalistic and discrete-trial formats give similar language gains. The 2013 trial sits right inside their averages.

Leigh et al. (2015) looked deeper and found that joint-attention and parent talk predict growth. Rhea’s data match that pattern, showing the same moderators inside an experiment.

Slater et al. (2020) seems to disagree. They saw extra hours help only mild-symptom toddlers, not severe. The gap is age: Paul studied toddlers, Rhea studied preschoolers. Severity matters more at 2 years; baseline language matters more at 4.

You do not have to pick one camp. Keep both drill and play in your toolbox. Start with a quick receptive-language probe. If the child scores low, run short, clear trials first. If the child follows pointing and shared looks, move to naturalistic play while you coach parents to talk. Either path can grow words in 12 weeks.