Increasing Relationship Between Negative Emotionality and Conduct Problems During Childhood: A Cross-Sectional Behavioral Genetic Analysis

Abstract

Age difference in the etiology of the relationship between childhood negative emotionality (NE) and conduct problems (CP) has not been previously investigated. Mothers of 662 pairs of twins completed questions on the emotionality (NE) scale of the EAS temperament survey and the CP scale of the Strengths and Difficulties Questionnaires (SDQ) via a telephone interview. Twin data were analyzed separately in younger (ages 3 to 7 years; mostly pre-schoolers) and older children (ages 8 to 13 years; mostly elementary school children). The phenotypic correlation between NE and CP increased from 0.33 among younger twins to 0.43 among older twins. Bivariate model-fitting analysis was performed to determine age difference in the etiology of the relationship between NE and CP. Among younger twins, the correlation between NE and CP was entirely explained by additive genetic factors common to NE and CP. Among older children, however, a small but significant amount of unique environmental correlation emerged to account for about 47% of the phenotypic correlation between NE and CP. The remaining 53% of the phenotypic correlation was due to shared additive genetic factors. We speculate that environmental factors associated with school adjustment may exert influences on the relationship between NE and CP among elementary school children.

The South Korean Twin Registry

“…The Standard Progressive Matrices-Plus version (Raven, 2008) has been used for assessment of cognitive abilities for school-aged twins. To measure problem behaviors and mental health traits, the Strengths and Difficulties Questionnaire (Goodman, 1997), hostility (Koskenvuo et al, 1988), Launey-Slade Hallucination Scale -Revised (Launay & Slade,1981), clinical symptoms of Personality Assessment Inventory (Morey, 1991), Center for Epidemiological Studies-Depression scale (Radloff, 1977), and Maudsley Obsessive-Compulsive Inventory (Hodgson & Rachman, 1977), and hwabyung (anger syndrome), have been administered to adolescent and young adult twins (Hur, 2006(Hur, , 2007b(Hur, , 2008(Hur, , 2009b(Hur, , 2014(Hur, , 2015Hur et al, 2015;Hur, Cherny et al, 2012;Hur, Choi et al, 2018;Hur & Jeong, 2008;Hur & Rushton, 2007). To assess physical and psychological family environment, the Family Asset Questionnaire and the Family Adaptability and Cohesion Scale (Olson et al, 1985) have been administered to twins or parents of twins.…”