Who are the incredible authors, what is the full title of the study, and what year was it published?
Authors: Megumi Kushima, Reiji Kojima, Ryoji Shinohara, Sayaka Horiuchi, Sanae Otawa, Tadao Ooka, Yuka Akiyama, Kunio Miyake, Hiroshi Yokomichi, Zentaro Yamagata, and the Japan Environment and Children’s Study Group
Title: Association Between Screen Time Exposure in Children
at 1 Year of Age and Autism Spectrum Disorder at 3 Years of Age
The Japan Environment and Children’s Study. JAMA Pediatrics 2022; 176(4):384-391.
Year: 2022
What is the study about?
In this study, the relationship between screen time exposure in children at 1 year of age and autism spectrum disorder (ASD) at 3 years of age was investigated. The focus was on whether there is a link between screen time and the diagnosis of ASD in early childhood, using maternal reported data. A large birth cohort in Japan was used to analyze the data, with the aim of identifying potential risk factors associated with ASD in children who have been exposed to excessive screen time.
What previous research is there on this topic?
Studies in 2019 and 2020 have suggested that the duration of screen time might be associated with ASD characteristics and brain morphology specific to ASD. However, cross-sectional studies investigating the association between screen time and ASD have yielded inconsistent results. Another environmental factor, electromagnetic fields, has also been linked to health concerns and screen exposure. Experiments with mice have demonstrated that high-frequency electromagnetic fields can affect neurotransmitters and behavior. Research has also identified low-frequency and high-frequency electrical stimulation, microwave irradiation, and light stimulation as potential contributors to autism-like symptoms, with evidence suggesting that such factors may impact neurodevelopment during infancy.
What methods were used in the study?
Sample
The Japan Environment and Children’s Study (JECS) collected data from 100,000 pregnant women across Japan from January 2011 to March 2014. The nationwide, prospective birth cohort study aimed to assess the impact of environmental factors on children’s health and development. For this study, researchers analyzed a dataset of 84,030 mother-child dyads using maternal self-reported questionnaires. The data were collected on the child’s screen time exposure, the presence or absence of autism spectrum disorder (ASD) at age 3, maternal mental health, mother-child attachment, family income, child’s sex, and ASD predisposition at age 1. The study excluded stillbirths, miscarriages, children with cerebral palsy, and those with missing data. All participants provided written informed consent, and the study was conducted according to the ethical guidelines for medical and health research involving human subjects.
Data Collection
To gather the data for the study, self-administered questionnaires were utilized to collect information from mothers. The questionnaires were designed to acquire various factors including the child’s screen time at 1 and 3 years of age, autism spectrum disorder (ASD) diagnosis at 3 years of age, maternal mental health, mother-child attachment, family income, and ASD predisposition at 1 year of age. The mothers were asked to report the hours per day their child spent watching television, using a computer, using a smartphone, and playing video games.
Additionally, the Japanese version of the K6 scale and the Bonding Scale were used to collect the maternal mental health and mother-child attachment data, respectively. The study also obtained data on the child’s sex, highest education level achieved by the mother and father, and whether the child had ASD predisposition at 1 year of age.
Maternal Nurturing
Maternal nurturing attitudes and abuse are considered as adjustment variables to control for their potential confounding effects on the relationship between screen time exposure in children at 1 year of age and the subsequent diagnosis of autism spectrum disorder (ASD) at 3 years of age. The study aimed to minimize the impact of these factors on the observed association between screen time exposure and the subsequent diagnosis of ASD. Parent-child interactions and child’s social-emotional development have been found to be affected by nurturing attitudes, while abuse/neglect may have persistent effects on children’s stress responses and exposure to toxic stress-related paradigms that affect brain development.
What were the findings?
The study found that longer screen time exposure at 1 year of age was associated with a higher risk of autism spectrum disorder (ASD) diagnosis at 3 years of age in boys, but not in girls. Boys with more screen time exposure had higher odds of being diagnosed with ASD at 3 years of age than those with less exposure. These results held true regardless of maternal mental health, mother-child attachment, family income, child’s sex, and ASD predisposition at 1 year of age. The study did not find a significant association between screen time exposure at 3 years of age and the subsequent diagnosis of ASD at 3 years of age.
What are the strengths of the study?
The study authors concluded that the findings of the study were reliable because the analysis was conducted using a large birth cohort dataset representative of the Japanese population.
What are the limitations of the study?
The study has some limitations, such as the use of parental reports to assess both screen time and ASD, which could have led to reporting bias. Additionally, ASD is usually diagnosed by medical institutions when children are 3 years old or older, and milder cases may not be diagnosed at that stage, resulting in a potential bias towards severe cases. To address this, the study performed a sensitivity analysis to identify any unmeasured confounding factors that could have affected the results. Despite this, residual confounding remained, suggesting that other factors could be involved in the relationship between screen time and ASD.
Can I read the full study somewhere?
Check it out right here.
The Causes of Autism 