The purpose of this study was to quantitatively examine the influence of child-rearing attitudes and bullying damage experience on the number of symptoms of conduct disorder(CD) using multivariate analysis. In this study a self-reported cross-sectional survey of children detained at Juvenile Classification Homes was conducted all over Japan. Valid responses were N＝1,339, age M＝16.87, SD＝1.61, boys N＝1,153, girls N＝186. A hierarchical multiple regression analysis was performed with the total score of 15 symptomatic items of CD as the dependent variable. The following factors were introduced in the multiple regression model: gender, age, age at first-onset of delinquency, callous-unemotional trait, attention-deficit/hyperactivity disorder(ADHD), the autism-spectrum quotient, the interpersonal reactivity index(IRI), the error proneness Questionnair, child-rearing attitudes and bullying damage. Other risk factors for CD were added to the independent variables to consider spurious correlations. Taking into account the influence of various independent variables, the results of the analysis suggested that parent-child discord, physical abuse, neglect and bullying damage were risk factors for CD. The neglect were risk factors when inattention of ADHD or the Perspective Taking of IRI were high. The Fantasy of IRI were decrease that relationship physical abuse and CD.

Most of the studies on social nuisance behaviors have included university students as subjects. Although studies have examined the factors associated with social nuisance behaviors, the relationship between social nuisance and empathy remains unexplored. This may be because of a failure to consider subject-specific empathy, such as with whom one can empathize and to what extent. Therefore, we created an empathy measure for each subject toward whom one empathizes, and investigated its associations with social nuisance behaviors. A survey of college students (n＝105) did not show whether the level of empathy toward people with low association level was correlated with social nuisance behaviors. Instead, low empathy for close people (in both cognitive and emotional domains) was found to be related to the ease of performing social nuisance behaviors. This suggests that it is more important to improve one’s ability to empathize with those close to oneself than to increase empathy for all people. The empathy scale used in this study needs to be validated in the future.

The relationship between personality traits and delinquency/crime, with the five-factor model as the basis, has been previously studied. However, only a few studies have examined the relationship between personality traits and delinquency, and no studies have been conducted in Japan. Therefore, we administered the Big Five Scale (BFS), a five-factor model personality test, to juvenile delinquents (N＝104) detained in a juvenile classification home, and investigated the relationship between tendency to repeat delinquency (self-report delinquency scale results) and its different types. The results of a logistic regression analysis and multiple regression analysis revealed that those with low agreeableness and conscientiousness were more likely to be delinquent. Furthermore, those with low agreeableness were more likely to engage in violent delinquency. These findings are consistent with overseas studies, and indicate that understanding the personality of juvenile delinquents using the five-factor model can be useful in Japan.