Digital and Blended Lifestyle Interventions for Preschool-Aged Children and Families With a Low Socioeconomic Position and the General Population: Scoping Review.

Background: Many unhealthy habits develop in early childhood and can lead to long-term health risks, which disproportionately affect children with low socioeconomic position (SEP). Digital and blended lifestyle interventions can promote healthier lifestyles, yet families with lower SEP remain underrepresented and face unique barriers to healthy behaviors and intervention access. As a result, it remains unclear which intervention characteristics are most effective for these populations. Objective: This study aimed to identify and map digital and blended lifestyle interventions targeting preschool-aged children and explore how intervention characteristics and reported effectiveness patterns differ between interventions for the general population and low SEP families. Methods: A search across Scopus, Web of Science, Cochrane Library, ERIC, and ACM Digital Library was conducted. Studies were eligible if they (1) targeted preschool-aged children (6 months to 5 years) or caregivers, (2) evaluated a digital or blended lifestyle intervention, and (3) addressed at least one behavioral domain (nutrition, physical activity, sedentary behavior, sleep, and oral health). Studies focusing on pregnant women, children aged >5 years, or interventions delivered solely nondigitally were excluded. Screening and prioritization were supported by artificial intelligence-assisted software (ASReview; Utrecht University). Data covered intervention targets, populations, theoretical and guideline foundations, delivery modes and settings, and persuasive systems design features. Intervention characteristics and effectiveness categories were synthesized descriptively. The methodological quality of quasi-experimental studies was assessed using the Joanna Briggs Institute critical appraisal tools. Results: A total of 77 studies describing 54 interventions were included. Of these, 35 targeted the general population, and 19 focused solely on low SEP families. Interventions were similar across groups: typically parent-focused, targeting multiple lifestyle domains, and informed by theories, frameworks, or evidence-based guidelines. Low SEP interventions more often used text messaging, included fewer persuasive design features, and tended toward single delivery channels. Effectiveness findings were mixed; no consistent patterns emerged when interventions were grouped by their characteristics. Among low SEP interventions only, less effective interventions more often targeted multiple behaviors and included more persuasive systems design features. Conclusions: To our knowledge, this is one of the first reviews to map digital and blended lifestyle interventions for preschool-aged children while comparing intervention characteristics and descriptive effectiveness patterns across general and low SEP populations. The review highlights heterogeneity in intervention characteristics and outcomes and identifies gaps where evidence is limited. These findings underscore the need to better represent low SEP families in intervention research, strengthen understanding of feasibility and contextual fit, and support multilevel approaches that reflect families' everyday contexts. However, the findings should be interpreted in light of several limitations, including the exclusion of gray literature, partial double-screening, the possibility that artificial intelligence-assisted prioritization may have omitted relevant studies, and variation in the reporting of intervention components across studies.