Abstract
In this study, the researcher used meta-analytic methods to calculate the effect sizes for protective factors and generalize the effect of protective factors by summarizing previous empirical resilience studies. In total, 24 meta-analyses were carried out from 21 prior studies, including 13 variables classified as protective factors of individual characteristics, 5 as protective factors of family connection, and 6 as protective factors of external support. In 14 of the meta-analyses, the precise estimates of the effect size of protective factors were found. In the other, the true effect size of protective factors were not found because of the existence of a moderator effect, and hence further empirical research is needed to confirm the nature of the effect size of protective factors. Based upon the meta-analytic findings, implications for prevention and intervention research, and future resilience studies are discussed.