Chen H, Yang T, Chen J, et al. - Sleep problems are more common in children with autism spectrum disorder (ASD). Bedtime resistance, anxiety, sleep onset delay, and daytime drowsiness in ASD children may be connected to core symptoms but not to developmental level. Sleep assessment should be incorporated in the routine of ASD visits in the clinic, and sleep hygiene instruction is just as important as biological factor treatment during the intervention.

• This is the first large-scale investigation into the sleeping habits of Chinese children with ASD.

• Using a cross-sectional design, 2 to 7-year-old children from 13 cities in China were involved: 1,310 with ASD (765 males and 393 females) and 1,158 with typically-developing (TD) children (1,077 males and 233 females).

• The incidence of sleep disorders in ASD children was considerably higher than in TD children, with bedtime resistance, sleep anxiety, sleep onset delay, and daytime sleepiness being the four aspects with the highest frequency of sleep problems.

• ASD children with sleep onset delay or sleep anxiety had higher Autism Behavior Checklist (ABC), Social Responsiveness Scale (SRS), and communication warning behavior scores.

• .ASD children with daytime sleepiness had higher ABC, SRS, and Child Autism Rating Scale scores, and ASD children with bedtime resistance had higher SRS total scores.

• There were no significant differences in neurodevelopmental levels.