Brief Report: Developmental Trajectories of Adaptive Behavior in Children and Adolescents with ASD.

Fujiura et al. (2018) tracked the kids with ASD for up to 10 years. Parents filled out the ABAS-3 every year. The team split the kids into three IQ groups and watched how daily-living, social, and communication skills changed.

The study ran at a large autism clinic. Kids entered between ages 2 and 9 and stayed through age 16. No one got a special treatment; the study just watched natural growth.

Adaptive scores climbed fast before age 8, then flattened. The plateau hit all IQ groups—high, medium, and low. Daily-living skills showed the biggest stall.

Girls and boys followed the same curve. Early talkers and late talkers both slowed down in middle school. The gap between autistic kids and same-age peers widened after age 10.

Charman et al. (2004) and Van Hanegem et al. (2014) saw steady preschool gains; T et al. now show those gains stop later. The story extends Giserman-Kiss et al. (2020), who found cognitive scores keep rising—so IQ growth does not guarantee adaptive growth.

Lin et al. (2026) add that teens with poor communication join fewer community activities. Together the papers say: skills and participation both freeze when teaching slows.

Reichard et al. (2019) tracked vocabulary and saw a small but steady climb through age 8. T et al. show the climb in real-life skills ends at about the same age, linking language and adaptive plateaus.

Do not assume teens will “grow into” daily tasks. Keep running goal plans for laundry, texting friends, and ordering food. Use middle-school IEP meetings to lock in adaptive goals, not just academic ones. Brief parent coaching each quarter can keep skills moving instead of stalling.