This study has two purposes:

Aim 1: To develop a Telehealth Early Intervention Program (TEIP) for children with ASD that will be carried out by parents at home when interact with their children; and to train parents in delivering developmental and behavioral techniques to their children. The participating families will be randomized in parallel to treatment and comparison groups for teaching the knowledge and techniques: (1) Treatment group: providing the training of TEIP for parents via telehealth modalities as they learn critical skills with their child with the goal of increasing multidimensional child developments. Intervention provider will provide the training for parent-child dyad interaction to work with parents to implement these strategies at home environment; and (2) Comparison group: provide general care consultation of child development for parents.

Aim 2: To evaluate this program's effectiveness by measuring changes in a child's developments and behaviors. Investigator will evaluate child outcomes on the symptoms of ASD and multidimensional developmental functioning. Furthermore, investigator will measure the changes in the parent's knowledge and behaviors of parent-child interaction. Moreover, investigator will determine if parental participation in the intervention is associated with an improvement in parenting competences and decreased levels of stress.

In recent years, due to the rapid increase in the prevalence of autism spectrum disorder (ASD), early detection of these children is helpful for early diagnosis and intervention and better prognosis. Recent research supports the intervention in the daily life of children with autism in a naturalized way. Parents learn intervention skills and implement them in their lives, providing positive effects on children with autism. This type of intervention is called parent-mediated intervention. Pivot Response Training (PRT) is a home-based parent-child intervention model that uses "Applied Behavior Analysis" to integrate into children's daily life situations and teach children to respond appropriately to the many learning opportunities and social interactions in natural situations, reducing reliance on therapist supervision, and care services that hinder children from natural situations. However, there are many obstacles at present. In addition to insufficient resources, long waiting time for accessing services, and the COVID-19 Pandemic or future emerging infections interrupting in-person face-to-face services, remote guidance of parents to implement the intervention at home (telehealth) is another way to help children and families with developmental disabilities. This way of giving patients holistic health care is a new trend in providing early intervention services. Therefore, this study plans to first conduct team education and discussion, and then use our highly reliable screening tool to screen children aged 24-72 months for autism screening in the community and institutes. Those screened with a positive result will be referred to our early intervention center for comprehensive child development and behavioral follow-up. A total of 60 children over 24 months old diagnosed with ASD will participate in the telehealth intervention program. They will be randomly assigned to the intervention group or the comparison group. The intervention group (the telehealth group) will also receive a 16-week telehealth intervention with guidance, digital learning platform, teaching parents to learn intervention skills to improve children's attention and play ability, social communication, cognition, perceptual movement, and improve parents' management of children's behavior problems. The comparison group (telephone group) will receive 16-weeks of child development counseling through phone calls. This project aims to enhance the education and cooperation of the team, increase the awareness and understanding of ASD in the community, strengthen the use of relevant screening tools, provide an easy-accessed E-learning platform for parents, daycare or kindergarten caregivers or professionals to learn, and establish an evidence-based telehealth early intervention for autistic children. In this way, parents of autistic children would have more confidence and support to go for screening and intervention to achieve patient- and family-centered holistic care and enhance their compliance.

Inclusion Criteria:

• child's age within 24-72 months
• parental age greater than 18 years
• parents have a minimum 9 years of education year that can read Chinese.

Exclusion Criteria:

• Children with major sensory, motor or neurological impairment/disorder (e.g., uncorrected visual or hearing loss, or severe brain damage)

Outcome assessor will be blinded for the group of participants