The heritability of conscientiousness facets and their relationship to IQ and academic achievement

The heritability of conscientiousness has been one of the least explored of the NEO PI domains. Here we focus on the facet scales of the conscientiousness domain, estimating both their heritability and their correlations with measures of IQ and academic achievement (Queensland Core Skills Test; QCST) in a sample of adolescent twins and their non-twin siblings. Our findings confirmed positive associations between IQ and the facets of Competence and Dutifulness (ranging 0.11-0.27), with academic achievement showing correlations of 0.27 and 0.15 with these same facets and 0.15 with Deliberation. All conscientiousness facets were influenced by genes (broad sense heritabilities ranging 0.18-0.49) and unique environment, but common environment was judged unimportant. A multivariate genetic analysis including Competence, Dutifulness, IQ (verbal, performance) and QCST scores showed that common variance was primarily explained by a general additive genetic factor (loadings ranging 0.15-0.84). Future multivariate genetic analysis which incorporates Openness to Experience dimensions may improve the interpretation of these findings. (c) 2005 Elsevier Ltd. All rights reserved.

A linkage study of academic skills defined by the Queensland Core Skills Test

This study used genome-wide linkage analysis to detect Quantitative Trait Loci (QTLs) implicated in variation in general academic achievement as measured by the Queensland Core Skills Test (QCST) (Queensland Studies Authority, 2004). Data from 210 families were analysed. While no empirically derived significant or suggestive peaks for general academic achievement were indicated a peak on chromosome 2 was observed in a region where Posthuma et al. (2005) reported significant linkage for Performance IQ (PIQ) and suggestive linkage for Full Scale IQ (FSIQ), and Luciano et al. (this issue) observed significant linkage for PIQ and word reading. A peak on chromosome 18 was also observed approximately 20 cM removed from a region recently implicated in reading achievement. In addition, on chromosomes 2 and 18 peaks for a number of specific academic skills, two of which were suggestive, coincided with the general academic achievement peaks. The findings suggest that variation in general academic achievement is influenced by genes on chromosome 2 which have broad influence on a variety of cognitive abilities.

Comparative academic performance of medical students in rural and urban clinical settings

OBJECTIVE To determine whether the academic performance of medical students learning in rural settings differs from those learning in urban settings. DESIGN Comparison of results of assessment for 2 full cohorts and 1 part cohort of medical students learning in rural and urban settings in 2002 (209 students), 2003 (226 students) and 2004 (220 students), including results for each specialist rotation in the 3rd year and end-of-year examinations in the 2nd and 4th years. SETTING University of Queensland School of Medicine, Brisbane. Students spent the whole 3rd year (of a 4-year graduate entry programme) conducting 5 specialist 8-week rotations in either the rural clinical division (rural students) or in Brisbane (urban students), all following the same curriculum and taking the same examinations. RESULTS For the 2002 cohort there were no statistically significant differences in academic performance between rural and urban students. For the 2003 cohort the only significant difference was a higher score for rural students in the end of the 4th-year clinical skills examination (65.7 versus 62.3%, P = 0.025). For the 2004 cohort, rural students scored higher in the 3rd-year mental health rotation (79.3 versus 76.2%, P = 0.038) and lower in the medicine rotation (65.5 versus 68.6%, P = 0.037). CONCLUSION Academic performance among students studying in rural and urban settings is comparable.