Development of prejudice against immigrants and ethnic minorities in adolescence: A systematic review with meta-analysis of longitudinal studies

Previous research highlighted that prejudice is already formed in early childhood, reaches a peak in middle childhood, and slightly decreases in late childhood, whereas the development of prejudice in adolescence was mostly unknown. This systematic review with meta-analysis aimed to comprehensively summarize and integrate prior longitudinal research on adolescents’ prejudice to address two main research questions: (a) how does prejudice develop in adolescence? (b) which factors are related to holding prejudicial attitudes in adolescence? Using multiple search strategies and applying a two-step selection process, a final set of 26 journal articles including a total of 30 samples (N = 23,513 participants) was found to match eligibility criteria and, thus, was included in the review. The meta-analytic findings highlighted that (a) prejudice does not change in adolescence; (b) interindividual differences in prejudice are well-established, they become increasingly strong with age, and they are inversely related to the time-lag between assessments; and (c) several individual, identity, and contextual factors are related to prejudice in different ways. More specifically, social dominance orientation, intergroup anxiety, identification with the national ingroup, and parental prejudice contributed to increasing later levels of adolescents’ prejudice, whereas intergroup friendship contributed to lessening it. Importantly, prejudice had comparable reverse effects on these factors, pointing to consistent bidirectional associations. These main findings are discussed considering their implications for future research and practice.