Mobile Health Intervention for Children With Autism

Hunan Normal University276 enrolled

Overview

This study is a randomized clinical trial conducted in China from January 2023 to July 2025. It aims to test whether a mobile health program delivered via WeChat, with or without additional human support, can help improve body weight outcomes in children with autism. Children aged 8 to 16 years with autism were randomly assigned to one of three groups: (1) usual care, (2) a 16-week WeChat-based lifestyle intervention, or (3) the same WeChat intervention plus weekly tele-group sessions led by a coach. The main outcome is the change in body mass index (BMI) z-score after 16 weeks. Secondary outcomes include the development of obesity over 6, 12, and 24 months, as well as changes in physical activity, screen time, eating habits, and other health behaviors. A total of 276 families participated. The results will help understand whether digital health programs can be an effective and scalable option for supporting healthy lifestyles in children with autism.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Enrollment

276

Conditions

Autism Spectrum Disorder Obesity Pediatric Overweight

Interventions

Standard Lifestyle RecommendationsBEHAVIORAL

Participants continue to receive routine clinical care and receive 1-time written standard recommendations on healthy eating and physical activity for children. No digital support, individualized feedback, or scheduled coaching is provided.

WeChat-Based Mobile Health InterventionBEHAVIORAL

A culturally adapted, family-based behavioral lifestyle intervention delivered via WeChat for 16 weeks. Content is delivered through 3 prescheduled WeChat messages per week in health literacy-informed multimedia formats (e.g., short texts, infographics, and videos). The intervention targets healthy eating, physical activity, reduction of sedentary behavior, and parent-mediated behavior change strategies. It incorporates behavior change techniques including goal setting, self-monitoring, and positive reinforcement. Families receive automated prompts to complete weekly behavior-change tasks and standardized reminders.

Coach-Facilitated Tele-Group SessionsBEHAVIORAL

Weekly coach-facilitated tele-group sessions delivered remotely via Tencent Meeting. Sessions last approximately 20 to 30 minutes and typically include 6 to 8 families. The sessions are delivered according to a structured manual by trained research assistants with master's degrees in psychology or related fields. Session content focuses on reinforcing key intervention messages, reviewing progress, problem-solving barriers, facilitating peer exchange, and setting weekly family goals.

Eligibility

Sex: ALLMin age: 8 YearsMax age: 12 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Aged 8 to 12 years at the time of enrollment * Confirmed diagnosis of autism via prior clinical documentation, verified by the Childhood Autism Rating Scale, Second Edition (CARS-2) * Parent or legal guardian is able and willing to provide written informed consent for the child's study participation * The family has consistent smartphone access to receive and engage with the WeChat-based intervention * No baseline obesity, as defined by age- and sex-specific BMI cutoffs for Chinese children and adolescents Exclusion Criteria: * Meets the definition of baseline obesity per age- and sex-specific BMI cutoffs for Chinese children and adolescents * Has any medical or developmental condition that precludes safe participation in the remotely delivered lifestyle intervention * Unable to comply with the study intervention and assessment procedures * Parent or legal guardian refuses to provide written informed consent for the child's study participation

Outcomes

Primary Outcomes

Change in Body Mass Index (BMI) z-score

This metric is the primary continuous endpoint for obesity prevention in children with autism spectrum disorder. BMI is measured with calibrated medical-grade devices, guided by blinded assessors via real-time video calls. Longitudinal changes at 6-, 12-, and 24-month post-intervention follow-ups are secondary analyses.Age- and Sex-Standardized Body Mass Index (BMI) Z-Score. The z-score uses the updated national growth reference for Chinese school-aged children, aligned with WGOC criteria for epidemiological validity.As a standardized statistical measure of population mean deviations, this metric has no fixed theoretical minimum or maximum values.Higher scores mean worse outcomes (greater obesity relative to the reference population), while a z-score decrease indicates better outcomes, reflecting a clinically meaningful weight control benefit.

Time frame: Baseline (pre-intervention), the 16-week intervention (primary endpoint), 6-month, 12-month, and 24-month post-intervention follow-up visits.

Secondary Outcomes

Cumulative Incident Obesity

This metric is the key secondary endpoint for evaluating the long-term obesity prevention effect of the intervention, defined as the cumulative proportion of new-onset obesity among participants without obesity at baseline. Obesity is diagnosed strictly in accordance with the criteria of the Working Group on Obesity in China (WGOC), i.e., BMI at or above the age- and sex-specific 95th percentile for Chinese children and adolescents, using the same standardized measurement protocol as the primary outcome.

Time frame: At the 6-month, 12-month, and 24-month post-intervention follow-up visits.

BMI z-score Responder Status

This is a binary supportive secondary outcome, defined as the proportion of participants who achieve a reduction in BMI z-score of ≥0.20 from baseline to the end of the 16-week intervention, used to assess the clinical significance of the intervention effect. The BMI z-score is calculated using the exact same standardized protocol as the primary outcome. This outcome is reported as the responder rate (range: 0% to 100%), with a higher responder rate indicating a greater clinical benefit of the intervention on weight-related outcomes.

Time frame: The 16-week intervention.