Prosocial behavior and loneliness among children and adolescents: a systematic review and meta-analysis

Loneliness, understood as the unpleasant feeling emerging when individuals perceive dissatisfaction with the quantity and/or quality of their social relationships, represents an indicator of distress. In adolescence, it is frequently linked to bullying, with elevated loneliness observed among those who experience both bullying and cyberbullying. In contrast, prosocial behavior – voluntary actions aimed at benefiting others – acts as a protective factor against loneliness during developmental years and shows a negative association with bullying victimization. This study aims to conduct a meta-analysis to evaluate the relationship between prosocial behavior and loneliness in youth. Specifically, we seek to accomplish two objectives: (1) to analyze the strength of the association between prosocial behavior and loneliness using data from crosssectional studies; (2) to test the hypothesis that prosocial behavior has a longitudinal effect in reducing feelings of loneliness. Moderators include age, historical period (pre-, during-, postpandemic), and informant type for prosocial behavior data (self-report vs. other-report) for Study 1; Study 2 also considers the time span between longitudinal waves. A systematic literature search was conducted in April 2024 across Scopus, Web of Science, and PsycInfo databases, identifying 18,705 articles. Following PRISMA guidelines, 45 studies were selected. Only studies with available data were included in the meta-analysis (19 for Study 1 and 5 for Study 2), resulting in 29 cross-sectional and 11 longitudinal observations focused on childhood and adolescence. These findings may offer insights for future research and support practitioners in promoting prosocial behavior as a potential protective factor against loneliness in school-age youths.