Comparison of dichotomized and distributional approaches in rare event clinical trial design: a fixed Bayesian design

This research was motivated by our goal to design an efficient clinical trial to compare two doses of docosahexaenoic acid supplementation for reducing the rate of earliest preterm births (ePTB) and/or preterm births (PTB). Dichotomizing continuous gestational age (GA) data using a classic binomial distribution will result in a loss of information and reduced power. A distributional approach is an improved strategy to retain statistical power from the continuous distribution. However, appropriate distributions that fit the data properly, particularly in the tails, must be chosen, especially when the data are skewed. A recent study proposed a skew-normal method. We propose a three-component normal mixture model and introduce separate treatment effects at different components of GA. We evaluate operating characteristics of mixture model, beta-binomial model, and skew-normal model through simulation. We also apply these three methods to data from two completed clinical trials from the USA and Australia. Finite mixture models are shown to have favorable properties in PTB analysis but minimal benefit for ePTB analysis. Normal models on log-transformed data have the largest bias. Therefore we recommend finite mixture model for PTB study. Either finite mixture model or beta-binomial model is acceptable for ePTB study.     

Those They Leave Behind: Paternal Incarceration and Maternal Instrumental Support

As the American imprisonment rate has risen, researchers have become increasingly concerned about the implications of mass imprisonment for family life. The authors extend this research by examining how paternal incarceration is linked to perceived instrumental support among the mothers of inmates' children. Results from the Fragile Families and Child Wellbeing Study (N = 4,132) suggest that recent, but not current, paternal incarceration is independently associated with less maternal perceived instrumental support and that this association persists after adjusting for a rich set of control variables, including prior perceived instrumental support. For families of recently incarcerated men, incarceration may be a double strike, simultaneously increasing the need for instrumental support while decreasing its availability when incarcerated fathers return to the community.     

Relationship Churning and Parenting Stress Among Mothers and Fathers

Researchers have documented the consequences of relationship instability for parenting stress but have given little attention to within‐partner relationship instability. In this study, the authors used data from the Fragile Families and Child Wellbeing Study (N = 3,544) to estimate the association between within‐partner relationship instability (known as churning or on‐again/off‐again relationships) and parenting stress. First, they found that by the focal child's 5th birthday about 16% of biological parents experience churning. Second, compared to being stably together with or stably separated from the child's other parent, churning is associated with greater parenting stress for both mothers and fathers. Because parenting stress is the same or higher among churners compared to their counterparts who stably separate, this suggests that, more than a change in partner, relationship instability—whether within or across relationships—is tied to parenting stress.     

Dissemination to research subjects: operationalizing investigator accountability

Recent articles have argued from principles of bioethics for the right of research subjects to receive the results of the studies in which they have participated. We argue that accountability is a powerful tool of meso-level analysis appropriate to reasoning about answerability in research ethics, and that it captures the responsibility of researchers to disseminate study results to research subjects. We offer the following features of the research situation as relevant to the manner of dissemination to study subject, in addition to factors already proposed in the literature (risk and impact on health outcome): (a) features of the research subject in relation to identity, personal investment, disease, and community; (b) characteristics of the research study and field of inquiry in relation to certainty and significance; and (c) relationships among the research subjects and the healthcare workers involved in their care and in the research.     

Does Privatization Protect Natural Resources? Property Rights and Forests in Guatemala

Objectives . Property rights are central to debates about natural resource policy. Governments traditionally have been seen as the appropriate custodians of natural resources for their citizens. More recently, many argue the privatization of property rights will ensure that users have incentives to manage their resources well. Common property, to the extent it is discussed at all, is seen as leading to the tragedy of the commons. We evaluate these claims by assessing property rights and forest conditions in two private and three communal forests in Guatemala. Methods . Data on biological and social phenomena from five forests (151 plots) and their associated communities were collected using the International Forestry Resources and Institutions Research Program protocols. Ordinary least squares regression was used to analyze four models. We examined t -scores for differences in coefficients for the different models. Results . The models demonstrate that de jure property rights are not a powerful predictor of variations among the sampled forests. Conclusions . We argue that de facto institutions and their enforcement are much more important than de jure property rights to forest management. Communities holding a forest in common can, under certain circumstances, create institutions to manage their resources as successfully as—or more successfully than—private owners.     

A Literature Review of Organizational Behavior Management Interventions in Human Service Settings from 1990 to 2016

We reviewed the Journal of Applied Behavior Analysis (JABA), Journal of Organizational Behavior Management (JOBM), and Behavior Analysis in Practice (BAP) from 1990 to 2016, to identify articles that evaluated organizational behavior management interventions in a human service setting. Of those articles, 75 articles met the inclusion criteria for the review, 44 from JABA (1990 to 2016), 22 from JOBM (1990 to 2016), and 7 from BAP (2008 to 2016). We categorized each selected article by setting, employee population, client population, assessment, dependent variable, independent variable, and outcome measures. Results from the review are discussed for all three journals. Recommendations are made to broaden the scope of population and dependent variable targets, include more assessments, and include outcome data when applicable.     

Evaluating the Temporal Location of Feedback: Providing Feedback Following Performance vs. Prior to Performance

In order to make feedback as effective as possible, it is important to understand its function in the three-term contingency (TTC) and the impact of various factors involved in delivering feedback. Timing of feedback is one factor that can affect the impact of feedback on learner’s behavior. An analysis of timing of feeback may help us getting closer to better understanding how feedback functions in the TTC. The purpose of this study was to evaluate the effects of feedback at different temporal locations. Specifically, feedback was provided either immediately (a) after a teaching session or (b) before the following teaching session, on teaching performance of undergraduate psychology students. The results indicated that feedback provided before the teaching session was more effective in improving teaching skills than feedback that was provided after the session. These findings suggest that feedback may function primarily as an antecedent to future performance and not necessarily as a consequence for past performance. However, the behavioral mechanism that explains these results is not yet clear. Future studies should investigate this further by manipulating the content of feedback prior to the teaching performance.