The Long-Term Effect of Early-Life Uncertainty on Mental Health in Adolescence and Adulthood: A Meta-Analysis.

Turbulent changes in early life are a hidden source of childhood trauma, increasing potential risks for mental illness. Many studies have identified the link between childhood uncertainty and mental health. However, research on the long-term effect of early-life uncertainty (EU) on mental health has not been systematically synthesized. This meta-analysis aims to provide a quantitative estimate of the association between EU and subsequent mental health outcomes. Eight electronic databases and gray literature were searched. Twenty-eight studies met our inclusion criteria: samples of non-clinical adolescents or adults and clear and valid assessments. Random-effect models were used to calculate the pooled effect sizes of EU on internalizing problems, externalizing problems, and well-being. Meta-regression and subgroup analysis were used to explore potential moderators. Results indicated small to moderate associations involving EU and internalizing problem ( r  = .28; 95% confidence interval [CI] [0.228, 0.326]) and externalizing problem ( r  = .16; 95% CI [0.102, 0.220]). EU was not significantly associated with well-being ( r  = -.41; 95% CI [-0.738, 0.071]). Furthermore, moderator analyses found that composite uncertain experiences in childhood had a stronger negative effect than single experiences. EU was a stronger predictor of mental health problems in adults than in adolescents. Cross-sectional studies would amplify the correlation between EU and mental illness compared to longitudinal studies. In the future, childhood uncertain and unpredictable risks should receive more attention. More research needs to focus on positive psychological indicators and samples from non-Western countries.