Impact of Screen Time on Language Development and Vocabulary Acquisition in Early Childhood: A Systematic Review

Language development in the first few years of life is critical for later academic and social success. With the increasing use of digital devices among preschoolers, there have been concerns about the potential impact of screen time on language outcomes. Existing research presents mixed findings, making it necessary to synthesize current evidence. This systematic review aimed to examine and synthesize empirical evidence on the relationship between screen time and language development in early childhood, with emphasis on factors such as device type, content quality, socioeconomic status, and parent-child interaction. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted in the Cochrane Library, PubMed, Medical Literature Analysis and Retrieval System Online (MEDLINE), EBSCO Open Dissertations, ScienceDirect, and Clinicaltrials.gov for studies published between January 1, 2020, and February 17, 2025. Our inclusion criteria required studies published in the English language, assessed screen time exposure, and measured language outcomes in typically developing preschoolers. Data were extracted using a standardized form. The risk of bias was assessed using the Cochrane Risk of Bias 2 (RoB 2), the Risk Of Bias In Non-Randomized Studies of Interventions (ROBINS-I), and the Joanna Briggs Institute (JBI) Critical Appraisal tools. The overall certainty of the evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. A total of eight studies met the inclusion criteria, mostly consisting of cross-sectional studies that involved diverse patient populations with sample sizes ranging from 83 to 4,907 participants. The participants were primarily children aged three to six years and/or their parents. These studies mainly focused on measuring the duration of screen time, which averaged between approximately 1.39 and 2.65 hours per day. One study analyzed 44 mobile applications for their learning goals and educational potential. The most commonly reported outcomes were related to language development and vocabulary acquisition, which were assessed through parental surveys and developmental scales. Synthesized evidence suggests that high levels of unsupervised or passive screen time are often linked to weaker language development outcomes in preschoolers. However, screen use that is interactive, educational, and involves caregiver participation appears to mitigate these potential effects. The overall certainty of this evidence, however, remains limited. Future research should prioritize consistent measurement approaches and explore long-term impacts.