Maternal factors and one-year-olds’ screen time: A cross-sectional study using birth cohort data from the Japan Environment and Children’s Study (JECS)

ABSTRACT

Japanese studies have reported that one-year-olds have the longest media exposure among preschoolers. This cross-sectional study assesses associations between the screen time of 12–17-month-old children and their mothers’ characteristics. Using data from the Japan Environment and Children’s Study (JECS), we analyzed 86,938 singletons whose primary caregivers were their mothers. Screen time was defined as time that mothers allowed their children to watch TV, DVDs, and/or other media, categorized into two groups, “less-than-4-hours” and “4-hours-or-more per day.” The independent variables were children’s sex, mothers’ age, educational attainment, media usage, employment status, frequency of outings, and the existence of caregivers other than the mother. We considered additional factors including scores on the Kessler Psychological Distress Scale ;(K6) and Mother-to-Infant Bonding Scale, Japanese version (MIBS-J). Ninety percent of one-year-olds viewed media content. A multivariate regression analysis revealed that the mother’s media usage was the strongest predictor that a one-year-old would have long screen time (>4 hours/day). A mother’s higher educational attainment and employment status predicted a decreased likelihood of a child’s long screen time. MIBS-J (anger and rejection and impaired bonding) showed very a slight association, and the child’s sex, mother’s age, and K6 had no association with the child’s screen-time.

Impact summary

Prior State of Knowledge: International guidelines recommend no screen time for one-year-olds. However, Japanese studies have reported that one-year-olds have the longest screen time among preschoolers. Systematic reviews have indicated that a child’s characteristics, family and social context, or ethnicity are factors that influence a child’s screen time.

Novel Contributions: This large-scale, Japanese survey targeting only one-year-olds contributes to knowledge of the possible predictors of children’s long screen time. Some findings were similar to previous studies, and some were different. The results differed greatly from international recommendations for the screen time for one-year-olds.

Practical Implications: The findings indicate the need for policymakers to develop practical guidelines for promoting rather than prohibiting behavioral changes in the screen time of children. They also suggest the possibility for mothers to reduce the screen time of their children by controlling their own media exposure.

KEYWORDS:

• Infants
• Japan environment and children’s study (JECS)
• maternal psychological distress
• media use
• mother–infant bonding
• preschool
• screen time
• screen view
• television
• Japan

Acknowledgments

We would like to thank all the participants who took time to complete the questionnaire during the years of this national cohort study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Availability of data and materials

Data are unsuitable for public distribution due to ethical restrictions and the legal framework of Japan. It is prohibited by the Act on the Protection of Personal Information (Act No. 57 of 30 May 2003, amendment on 9 September 2015) to publicly deposit data containing personal information. Ethical Guidelines for Medical and Health Research Involving Human Subjects enforced by the Japan Ministry of Education, Culture, Sports, Science and Technology and the Ministry of Health, Labour and Welfare also restrict the open sharing of the epidemiologic data. All inquiries about access to data should be sent to [email protected]. The person responsible for handling inquiries sent to this email address is Dr. Shoji F. Nakayama, JECS Programme Office, National Institute for Environmental Studies.

Ethics approval and consent to participate

The study protocol was approved by the Institutional Review Boards of Epidemiological Studies of the Ministry of the Environment, Japan and by the Ethics Committees of all participating institutions. The JECS was conducted according to the Declaration of Helsinki and Japanese Ethical Guidelines for Epidemiological Research published by the Ministry of Education Culture, Sports, Science and Technology and the Ministry of Health, Labour, and Welfare, Japan. Written informed consent was obtained from all participants before their participation. The study was registered with the UMIN Clinical Trials Registry System.

Members of the Japan Environment and Children’s Study (JECS) Group as of 2020

Michihiro Kamijima (principal investigator, Nagoya City University, Nagoya, Japan), Shin Yamazaki (National Institute for Environmental Studies, Tsukuba, Japan), Yukihiro Ohya (National Center for Child Health and Development, Tokyo, Japan), Reiko Kishi (Hokkaido University, Sapporo, Japan), Nobuo Yaegashi (Tohoku University, Sendai, Japan), Koichi Hashimoto (Fukushima Medical University, Fukushima, Japan), Chisato Mori (Chiba University, Chiba, Japan), Shuichi Ito (Yokohama City University, Yokohama, Japan), Zentaro Yamagata (University of Yamanashi, Chuo, Japan), Hidekuni Inadera (University of Toyama, Toyama, Japan), Takeo Nakayama (Kyoto University, Kyoto, Japan), Hiroyasu Iso (Osaka University, Suita, Japan), Masayuki Shima (Hyogo College of Medicine, Nishinomiya, Japan), Youichi Kurozawa (Tottori University, Yonago, Japan), Narufumi Suganuma (Kochi University, Nankoku, Japan), Koichi Kusuhara (University of Occupational and Environmental Health, Kitakyushu, Japan), and Takahiko Katoh (Kumamoto University, Kumamoto, Japan).

Additional information

Funding

This study was funded by the Ministry of the Environment, Japan. The findings and conclusions of this article are solely the responsibility of the authors and do not represent the official views of the government.

Notes on contributors

Mai Fujii

Mai Fujii, (PHN, PhD) is a researcher at Center for Baby Science, Doshisha University, Japan. Her study using Japanese birth cohort data of the Japan Environment and Children’s Study (JECS) focuses on children and media use or dwelling environment.

Yasuyuki Kawanishi

Yasuyuki Kawanishi, M.D., Ph.D. is a researcher at the Center for Baby Science, Doshisha University.

Fusako Niwa

Fusako Niwa, MD, PhD is a Program-Specific associate Professor of the Kyoto Regional Centre for Japan Environment and Children’s Study at Graduate School of Medicine, Kyoto University. She is also a neonatologist and pediatrician, and her research focuses on neonatal endocrinology related primarily to adrenal and thyroidal function as well as child development.

Kyoko Hirabayashi

Kyoko Hirabayashi, Ph.D, is a Program-Specific Senior Lecturer at the Kyoto Regional Centre for Japan Environment & Childrens Study, Kyoto University. She has been working in this Centre for nearly ten years. Her research fields are social medical sciences, child studies, and peace studies.

Kumiko Tsuji Kanatani

Kumiko T Kanatani, MD, MAS is a Lecturer in Kyoto University, where she engages in a national birth cohort, Japan Environment and Children’s Study. Her research centers on the health effects of air pollution including Asian sand dust. She holds an M.A.S degree in Clinical Research from University of California, San Diego.

Takeo Nakayama

Takeo Nakayama, MD, PhD, is a Professor of the Department of Health Informatics, School of Public Health, Kyoto University, Japan. His research interest is broad, especially epidemiology, evidence-based health care, and health communication. He is the chairperson of the steering committee of Minds Guideline Center at the Japan Council of Health Care Quality. He is also working as a program supervisor of the Japan Agency for Medical Research and Development.