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A large body of research indicates that the liability to develop schizophrenia is largely genetically mediated, although phenotypic expression requires environmental triggers/insults and/or epigenetic and/or stochastic factors. In an effort to identify the precise environmental factors that precipitate a predisposition to schizophrenia, researchers have implemented a high-risk model-the prospective study of offspring born to schizophrenic parents. As it is difficult to ascertain exactly which of the "high-risk" participants will actually develop the disorder, we examined the validity of an experimental MMPI scale, Schizophrenia Proneness (SzP), and the Moldin-Gottesman psychometric index to identify such individuals. Results suggest that the SzP scale can be an effective predictor of schizophrenia-related psychoses. A revised psychometric index is offered for further study.

T he roles of genetic and environmental influences on stressful life events were examined in 3938 twin pairs (MZ, same-sex DZ, and opposite-sex DZ) using a sex-limitation model. Life events were assessed by personal interview, and were categorized as being either personal (i.e., events that occur directly to the individual) or network (i.e., events that occur to someone within the individual's social network, thus affecting the individual indirectly). Consistent with previous reports, genetic factors were found to exert more influence on personal events than network events. Genetic correlations between males and females suggest that many of the same genetic factors are acting within both genders.

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McNulty, Harkness, Ben-Porath and Williams recently developed Personality Psychopathology Five (PSY-5) scales for the Minnesota Multiphasic Personality Inventory-A (MMPI-A). This study examined these new scales in a sample of 545 adolescents receiving inpatient psychiatric treatment. Item-level principal components analyses were employed to determine the internal structure of each PSY-5 scale and to aid in the creation of facet subscales for each PSY-5 scale. Results suggest that the MMPI-A PSY-5 scales display adequate internal consistency and our findings generally replicate the original work of McNulty et al. but also extend this work by showing that several of the PSY-5 scales may also be subdivided into meaningful lower level dimensions. These facet subscales for each of the MMPI-A PSY-5 scales are offered for further study.