Effects of unmeasured heterogeneity in the linear transformation model for censored data

We investigate the effect of unobserved heterogeneity in the context of the linear transformation model for censored survival data in the clinical trials setting. The unobserved heterogeneity is represented by a frailty term, with unknown distribution, in the linear transformation model. The bias of the estimate under the assumption of no unobserved heterogeneity when it truly is present is obtained. We also derive the asymptotic relative efficiency of the estimate of treatment effect under the incorrect assumption of no unobserved heterogeneity. Additionally we investigate the loss of power for clinical trials that are designed assuming the model without frailty when, in fact, the model with frailty is true. Numerical studies under a proportional odds model show that the loss of efficiency and the loss of power can be substantial when the heterogeneity, as embodied by a frailty, is ignored. An erratum to this article can be found at     

Substance use and vulnerability to sexual and physical aggression: a longitudinal study of young adults

Using data from 2,170 individuals who participated in Waves 8 (age 23) and 9 (age 29) of a multiyear panel study, this study examined whether alcohol and marijuana use in young adulthood increase one's risk for experiencing subsequent sexual or physical assault victimization, whether victims' own violent behavior or involvement in the sale of drugs explain any effects of substance use on victimization, and whether these associations differ by gender. Controlling for prior victimization, we found that marijuana use, but not alcohol use, predicted women's and men's subsequent sexual victimization and men's subsequent physical assault victimization, and that heavy alcohol use, but not marijuana use, predicted women's subsequent physical assault victimization. Whereas the links from marijuana use to victimization were explained by users' own violent behavior, the link from alcohol use to women's physical assault victimization was not.     

Demographic and situational factors affecting injury, resistance, completion, and charges brought in sexual assault cases: what is best for arrest?

This study examines demographic and situational factors in an effort to predict whether or not a complainant was injured, used resistance, experienced a completed assault, and whether charges were brought against the offender. If the accused had consumed alcohol or drugs, he was almost seven times more likely to be arrested. The complainant was six times more likely to report rape completion if she had consumed alcohol or drugs and if the complainant fell unconscious at any time during the attack she was significantly less likely to use a resistance strategy. The complainant's use of a compliance strategy at any time during the assault positively predicted not using a physical resistance strategy and sexual assault completion. The reporting of injury positively predicted use a physical resistance strategy and sexual assault completion. If the assault was completed, it was less likely that charges were pressed. Implications of these findings are discussed, and directions for future research are offered.     

Couple age discrepancy and risk of intimate partner homicide

Although national level studies in the United States and Canada find that extreme partner age discrepancy is a risk factor for intimate partner homicide in opposite-sex couples, these studies carry two caveats: They are limited to cohabiting marital or common-law couples and they are not detailed enough to explore alternative explanations for the age discrepancy-homicide risk association. Using the Chicago Homicide Dataset, which includes all homicides that occurred in Chicago from 1965 to 1996, we analyze the 2,577 homicides in which the victim was killed by a current or former legal spouse, common-law spouse, or heterosexual boyfriend or girlfriend, and in which the woman was at least 18 years of age. Within each of 14 categories of couple age discrepancy, we estimate the population of intimate heterosexual couples and calculate the population-based risk of homicide. The results replicate national level findings showing that the risk of intimate partner homicide is considerably elevated for couples with a large discrepancy between their ages-where the man is at least 16 years older than the woman or the woman is at least 10 years older than the man. This risk pattern occurs regardless of whether the man or the woman was the homicide offender. We then investigate whether the link between partner age discrepancy and homicide risk is explained by the offender's arrest record. Results show that the higher risk of intimate partner homicide for age discrepant couples is robust, and does not depend on the previous arrest record of the offender. Discussion addresses other possible explanations for the increased risk of partner homicide for age discrepant couples, and the practical implications of these findings.     

Correlates of load carriage and obstacle course performance among women

To examine correlates of the speed at which female soldiers carrying loads could cover 3.2 km on foot and traverse an obstacle course, 12 volunteers (mean +/- SD: 25.3 +/- 6 years, 166 +/- 7 cm, 61.3 +/- 7 kg) were timed over 3.2 km while carrying loads of 14, 27, and 41 kg, and while traversing an obstacle course with the two lighter loads. Pearson correlations showed that absolute VO_[2 max] and 3.2 km run time without a load were the best predictors of 3.2 km load carriage time for all loads. Also, larger subjects with greater muscle mass were able to carry the heaviest load faster than smaller, less muscular subjects, likely because the 41 kg load represented a smaller percentage of the former's bodyweight. Maximum number of sit-ups and push-ups, composite score of the Army Physical Fitness Test as well as body height were positively correlated with the speed at which some course segments were traversed.     

Child sexual abuse and attachment theory:are we rushing headlong into another controversy?

The child sexual abuse knowledge base has developed within a highly charged political and social context. As such, early theories of sexual abuse were susceptible to biases that reflected the larger sociocultural context. The purpose of this paper is to consider whether attachment theory as it is applied to child sexual abuse might also be susceptible to such biases. Although this paper concludes that attachment theory can potentially add an important dimension to the conceptualization of child sexual abuse and its dynamics, it is also suggested that attachment theory may remain at risk for becoming a vehicle for transmitting political and ideological agendas.     

Widowhood and spirituality: coping responses to bereavement

Nearly half of women age 65 or older are widows and nearly 70% of these women live alone. Because older women are three times more likely than their male counterparts to be widowed, widowhood has been labeled a primarily female phenomenon. This review article has two aims: (a) to discuss the impact of widowhood on the lives of older women and (b) to discuss how religion and spirituality may be used as coping methods for conjugal loss. After reviewing the literature the authors conclude that older women use religious coping as well as religious and spiritual beliefs and behaviors to facilitate positive adjustment to the loss of a spouse.