عنوان مقاله [English]
Research shows that two-thirds of the prisoners are likely to commit crimes again within the first three years of their release. It is critical to study the factors associated with committing crime again for public planning. In this essay, we try to identify not only the risk factors affecting this phenomenon by studying published articles about recidivism, but also, given the contradictory results of the research, we will examine the effect size of a summary of the research. This paper is a meta-analysis. In this study, Hege’s g index was selected as the indicator of the effect size of studies. The CMA2 software was used to calculate the effect sizes. The random summary effect size was 0.396, and the effect sizes of the variables from the highest to the lowest were that of personality disorder, low age of the offender, offenders’ attitudes, poor education, dysfunctional family, family history of crime, problematic personality traits, crime background, criminal associates, victim type, psychological disorders, alcohol and drug abuse, unemployment and status of residence, respectively. In conclusion, the summary effect size of risk factors, according to Cohen's classification, shows small and medium effects. The most studied risk factors were at the individual level, indicating that the individual's perception of committing crime in the research literature was overcome.