Multidimensional Developments and Free-Play Movement Tracking in 30- to 36-Month-Old Toddlers With Autism Spectrum Disorder Who Were Full Term.

Background: Few studies have investigated multidimensional developments and free-play movement performance in toddlers with an early diagnosis of autism spectrum disorder (ASD).

Objective: This study compared cognitive, motor, and behavioral developments and free-play movement performance in toddlers with ASD who were full term (FT-ASD), toddlers who were full term and are typically developing (FT-TD), and toddlers who were born preterm and had a very low birth weight (VLBW-PT).

Design: This was a prospective cross-sectional study.

Methods: Forty-five 30- to 36-month-old age-matched toddlers were recruited and divided into FT-ASD, FT-TD, and VLBW-PT groups. Their developments were examined using the Mullen Scales of Early Learning; the Peabody Developmental Motor Scales, Second Edition; the Child Behavior Checklist for Ages 1.5 to 5; and the Repetitive Behavior Scale-Revised. In addition, the toddlers' free-play movements were tracked in laboratory settings using an automatic movement tracking system.

Results: Toddlers with FT-ASD exhibited lower cognitive and motor scores and a higher degree of behavioral problems compared with toddlers with FT-TD or VLBW-PT. Furthermore, the movement tracking data in a free-play setting revealed that toddlers with FT-ASD displayed a higher degree of turning velocity, a higher moving time, and a higher frequency of moving toward the peripheral region compared with toddlers with FT-TD or VLBW-PT. Moreover, several motor developmental and movement-tracking indicators were found to correlate with behavioral problems and cognitive scores in toddlers with FT-ASD.

Limitations: The study results may have been affected by the small sample size, the cross-sectional design, and tracking only the whole body without subtle movements or segmental motions.

Conclusions: The findings suggest varied aspects of co-occurring developmental conditions and movement-based problems in toddlers with FT-ASD. Using standardized and sensitive measures for the early assessment of perceptuo-motor impairments is necessary for timely early intervention for such toddlers.