Analysis of genetic influences on the consistency and variability of the Big Five across different stressful situations

Several studies have demonstrated that individual differences in personality traits, known as the Big Five, have a genetic component. These personality traits are considered important predictors of everyday behaviour. In addition to personality traits there are also factors in the environment that govern behaviour. This dual influence on behaviour is statistically reflected in a P × S interaction. This study examines the genetic and environmental influences on the interactions between a person and his daily life environment for the Big Five. Fifty‐seven identical twin pairs and 43 fraternal twin pairs participated in this study. Trait related behaviour was measured in 30 different situations with the aid of an SR inventory. The heritability coefficients for the main effect of P were in the normal range, varying between 0.35 for Agreeableness and 0.53 for Conscientiousness. The heritability coefficients for the P × S interactions were moderately high, explaining between 26% and 69% of the total P × S variance. The consequences of these results for general and behavioural genetic research on the Big Five will be discussed. Copyright © 2001 John Wiley & Sons, Ltd.     

The test-retest reliability of the Form 90-DWI: an instrument for assessing intoxicated driving.

Although driving while intoxicated (DWI) is a pervasive problem, reliable measures of this behavior have been elusive. In the present study, the Form 90, a widely utilized alcohol and substance use instrument, was adapted for measurement of DWI and related behaviors. Levels of reliability for the adapted instrument, the Form 90-DWI, were tested among a university sample of 60 undergraduate students who had consumed alcohol during the past 90 days. The authors administered the instrument once during an intake interview and again, 7-30 days later, to determine levels of test-retest reliability. Overall, the Form 90-DWI demonstrated high levels of reliability for many general drinking and DWI behaviors. Levels of reliability were lower for riding with an intoxicated driver and for variables involving several behavioral conjunctions, such as seat belt use and the presence of passengers when driving with a blood alcohol concentration above .08. Overall, the Form 90-DWI shows promise as a reliable measure of DWI behavior in research on treatment outcome and prevention.     

Assessment of generalized anxiety disorder diagnostic criteria in the National Comorbidity Survey and Virginia Adult Twin Study of Psychiatric and Substance Use Disorders

The authors investigated measurement properties of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, generalized anxiety disorder (GAD) criteria in the National Comorbidity Survey and the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders (VATSPSUD). The two studies used different widely used instruments. There were significant (p < .001) differences in measurement of GAD due to age, study, and age-study interaction on item thresholds and factor loadings of GAD, especially when different stem-probe structures of interviews were taken into account. Item thresholds were estimated to differ by as much as -.74 as a function of age and .40 as a function of study. Despite these differences, factor scores derived from symptom criteria strongly predicted categorical diagnostic outcomes based on symptom count. It is concluded that interview structure, especially the stem-probe format of structured interviews, and wording had significant effects on study findings; that future studies in psychiatric epidemiology should use common structured interviews as much as possible; and that factor scores can be used in conjunction with sum scores as cut points to retain the advantages of both dimensional and categorical classification.     

Confirmatory Factor Structure and Psychometric Properties of the Multidimensional Peer Victimization Scale

The Multidimensional Peer Victimization Scale (MPVS; Mynard and Joseph, British Journal of Educational Psychology, 67, 51-54 2000) is a 16-item self-report scale that captures peer victimization across four dimensions: physical victimization, verbal victimization, social manipulation, and attacks on property. Performance of the scale has not been evaluated among older adolescents. We examined the factor structure, internal consistency reliability, and performance of the scale in two separate epidemiological U.S. samples representing different age groups: 9–14 year olds (N?=?610) and 15–17 year olds (N?=?524). The four-factor structure of the scale was affirmed in both samples, however; there was not metric invariance by gender in the younger age group. The scale and its subscales were found to have good internal consistency. Expected relationships between the MPVS and measures of irritability, anxiety, and depression were affirmed. Results support continued use of the MPVS among child and adolescent samples.     

Primary control and the consistency of interpersonal behaviour across different situations

Recent findings from person–situation studies suggest that primary control is a major factor underlying cross-situational consistency of individual behaviour. To provide evidence, we studied behaviour reflecting primary control in two modes: self-reports and observations of overt behaviour. Study I examined self-reports of 147 Ss in 15 interpersonal situations. In study II, 25 Ss were observed during role playing in five situations. The analysis focused on the degree to which Ss maintain consistent patterns of behaviour across different situations. Both studies revealed considerable degrees of consistency, thus confirming our conjecture. In the discussion attention is paid to the dispositional nature of primary control and the connections with secondary control. © 1998 John Wiley & Sons, Ltd.