A clinical perspective on ethical issues in genetic testing

Genetic testing is traditionally preceded by counselling to discuss its advantages and disadvantages with individuals so they can make informed decisions. The new technique of whole genome or exome sequencing, which is currently only used in research settings, can identify many gene mutations, including substantial numbers of mutations with unknown pathological effect; it may, therefore, threaten this balanced approach if it is used in a clinical setting. We discuss the ethical challenges of several approaches to pre- and postnatal DNA testing, individual privacy versus the interests of families and of scientists, and the clinician's duty to re-contact if new information or options become available.     

Alcohol expectancies in relation to personality and aggression among juvenile delinquents in Northern Russia

The relationships between alcohol expectancies, level of alcohol use, alcohol-related problems, aggression, and personality factors in 198 Russian male juvenile delinquents were assessed. A clustering procedure was used in order to establish main patterns of alcohol expectancies, yielding three major clusters. Level of alcohol use, alcohol-related problems, aggression, and personality factors were compared across the identified clusters. It was established that juvenile delinquents with a high level of positive alcohol expectancies and aggression represented a risk-group for higher involvement in drinking behavior as well as problem drinking, which in turn are related to specific personality traits. Implications of these findings for alcohol prevention among the youth are discussed.     

Applying the transtheoretical model to female and male perpetrators of intimate partner violence: gender differences in stages and processes of change

The Transtheoretical Model has been recently applied to men seeking services at battering intervention and prevention programs (Eckhardt, Babcock, & Homack, 2004; Murphy & Baxter, 1997). This study considers whether women arrested for intimate partner violence differ from male perpetrators in terms of stages of change and processes of change. No gender differences were found regarding stage of change. In general, all individuals presenting for treatment were in the early stages of change. The use of various processes of change was strongly related to stage of change, with individuals in the more advanced stages of change using more behavioral and experiential strategies to become nonviolent. However, except for the use of social liberation strategies, there were no gender differences in the use of the various processes. These findings suggest that the Transtheoretical Model may apply to female perpetrators equally as well as to male perpetrators. Intervention programs designed for male batterers using the Transtheoretical Model may also be helpful in the treatment of women arrested for domestic violence.     

The interaction of aging and 10 years of racing on ultraendurance running performance

The aim of this study was to examine the interaction between aging and 10 years of racing in endurance runners. Race-time data from 194 runners who had completed 10 consecutive 56-km ultramarathons were obtained. The runners were either 20.5 +/- 0.7, 30.0 +/- 1.0, 39.9 +/- 0.9, or 49.4 +/- 1.0 years old at their first race. Each runner's race speed was determined for each race over the 10 years. Data were analyzed using repeated-measures ANOVA, one-way ANOVA, and independent t tests and showed that performance improved and declined at greater rates for younger runners; younger runners had a greater capacity for improvement than older runners; approximately 4 years were required to reach peak racing speed, regardless of age; it was not possible to compete at peak speed for more than a few years; and the combined effects of 10 years of aging and racing neither improve nor worsen net performance. In conclusion, these data suggest that although these runners showed similar patterns of change in race speed over a 10-year period, the extent of change in performance was greater in younger than in older runners.     

Quasi-binomial zero-inflated regression model suitable for variables with bounded support

In recent years, a variety of regression models, including zero-inflated and hurdle versions, have been proposed to explain the case of a dependent variable with respect to exogenous covariates. Apart from the classical Poisson, negative binomial and generalised Poisson distributions, many proposals have appeared in the statistical literature, perhaps in response to the new possibilities offered by advanced software that now enables researchers to implement numerous special functions in a relatively simple way. However, we believe that a significant research gap remains, since very little attention has been paid to the quasi-binomial distribution, which was first proposed over fifty years ago. We believe this distribution might constitute a valid alternative to existing regression models, in situations in which the variable has bounded support. Therefore, in this paper we present a zero-inflated regression model based on the quasi-binomial distribution, taking into account the moments and maximum likelihood estimators, and perform a score test to compare the zero-inflated quasi-binomial distribution with the zero-inflated binomial distribution, and the zero-inflated model with the homogeneous model (the model in which covariates are not considered). This analysis is illustrated with two data sets that are well known in the statistical literature and which contain a large number of zeros.     

Methods for exploring treatment effect heterogeneity in subgroup analysis: an application to global clinical trials

Multi‐country randomised clinical trials (MRCTs) are common in the medical literature, and their interpretation has been the subject of extensive recent discussion. In many MRCTs, an evaluation of treatment effect homogeneity across countries or regions is conducted. Subgroup analysis principles require a significant test of interaction in order to claim heterogeneity of treatment effect across subgroups, such as countries in an MRCT. As clinical trials are typically underpowered for tests of interaction, overly optimistic expectations of treatment effect homogeneity can lead researchers, regulators and other stakeholders to over‐interpret apparent differences between subgroups even when heterogeneity tests are insignificant. In this paper, we consider some exploratory analysis tools to address this issue. We present three measures derived using the theory of order statistics, which can be used to understand the magnitude and the nature of the variation in treatment effects that can arise merely as an artefact of chance. These measures are not intended to replace a formal test of interaction but instead provide non‐inferential visual aids, which allow comparison of the observed and expected differences between regions or other subgroups and are a useful supplement to a formal test of interaction. We discuss how our methodology differs from recently published methods addressing the same issue. A case study of our approach is presented using data from the Study of Platelet Inhibition and Patient Outcomes (PLATO), which was a large cardiovascular MRCT that has been the subject of controversy in the literature. An R package is available that implements the proposed methods. Copyright © 2014 John Wiley & Sons, Ltd.     

Psychometric Properties of the Differentiation of Self Inventory‐Revised in Turkish Adults

The purpose of the current study was to examine the validity and reliability of (Journal of Marital and Family Therapy 2003, 29, 209) Differentiation of Self Inventory‐Revised (DSI‐R; Skowron & Schmit, 2003) in Turkish adults. The DSI‐R was translated, independently back‐translated, and revised. Two independent samples of adults over the age of 25 were used. The original 46‐item DSI‐R was not supported by the data derived from Sample 1 (n = 221). However, a revised 20‐item, four‐factor model fit the data well. This 20‐item model was subsequently cross‐validated with a second sample of Turkish adults (n = 187). Scale scores showed adequate internal consistency, 5‐week test–retest reliability, and satisfactory convergent and criterion‐related validity. It was concluded that Turkish DSI‐R (DSI‐T) is a valid and reliable measure to assess an individual's differentiation level. In light of the findings, implications for the use of the DSI‐T and ideas for future research are discussed.     

‘Drink a 12 box before you go’: pre-loading among young people in Aotearoa New Zealand

The practice of pre-loading—drinking large amounts of alcohol rapidly in private spaces prior to socialising in the night-time economy—has come to notice recently in the study of alcohol-related harm, but no studies have explored these phenomena in Aotearoa New Zealand. We used a theoretical framework developed with public health alcohol studies for understanding drinking cultures that conceptualises patterns of behaviours as arising within a dynamic interaction between forces of hedonism, function and control. We report findings from 34 focus groups conducted with 18–25 year olds as part of a project supported by the Marsden Fund, between 2011 and 2012, to investigate drinking cultures among young people. Our thematic analyses of participants’ accounts of pre-loading show that the term is in common use, applying to a range of practices motivated by price of alcohol but influenced by the pleasures of intoxication, the importance of peer processes and certain aspects of the regulatory system. We conclude with a discussion of the usefulness of the framework and the implications of the findings for public health policy that aims to reduce alcohol consumption and the harm that arises from it.