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There is insufficient knowledge concerning long-QT (LQT) 3 in the pediatric population to determine whether recommendations for more aggressive therapy in these patients are appropriate. An international multicenter review of 43 children with cardiac sodium channel (SCN5A) mutations and clinical manifestations of LQT syndrome without overlap of other SCN5A syndromes was undertaken to describe the clinical characteristics of LQT3 in children. Patients were aged 7.6 ± 5.9 years at presentation and were followed for 4.7 ± 3.9 years. There was significant intrasubject corrected QT interval (QTc) variability on serial electrocardiography. Forty-two percent presented with severe symptoms or arrhythmia and exhibited longer QTc intervals compared to asymptomatic patients. None of the 14 patients who underwent primary prevention implantable cardioverter-defibrillator (ICD) implantation received appropriate shocks in 41 patient-years of follow-up, while 2 of 6 patients who underwent secondary prevention ICD implantation received appropriate shocks in 30 patient-years of follow-up. Half of patients who underwent ICD implantation experienced inappropriate shocks or ICD-related complications. Mexiletine significantly shortened the QTc interval, and QTc shortening was greater in patients with longer pretreated QTc intervals. Two ICD patients with frequent appropriate ICD shocks showed immediate clinical improvement, with elimination of appropriate ICD shocks after mexiletine loading. In conclusion, severe symptoms are common in children with LQT3 and are associated with longer QTc intervals. ICD implantation is associated with significant morbidity. Mexiletine shortens the QTc interval, and it may be beneficial., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Maximum likelihood estimation techniques for subject-specific (SS) generalized linear mixed models and generalized estimating equations for marginal or population-averaged (PA) models are often used for the analysis of cluster-unit intervention trials. Although both classes of procedures account for the presence of within-cluster correlations, the interpretations of fixed effects including intervention effect parameters differ in SS and PA models. Furthermore, closed-form mathematical expressions relating SS and PA parameters from the two respective approaches are generally lacking. This paper investigates the special case of correlated Poisson responses where, for a log-linear model with normal random effects, exact relationships are available. Equivalent PA model representations of two SS models commonly used in the analysis of nested cross-sectional cluster trials with count data are derived. The mathematical results are illustrated with count data from a large non-randomized cluster trial to reduce underage drinking. Knowledge of relationships among parameters in the respective mean and covariance models is essential to understanding empirical comparisons of the two approaches.

Purpose: To present the first national prevalence estimates of psychological and physical intimate partner violence between adolescents in same-sex relationships., Methods: Analyses focus on 117 adolescents aged 12-21 years (50% female) from Wave II of the National Longitudinal Study of Adolescent Health who reported exclusively same-sex romantic or sexual relationships in the 18 months before interview. Items from the Conflict Tactics Scale were used to measure partner violence victimization. Data analysis included computation of prevalence estimates and a logistic regression analysis to assess associations between sociodemographic characteristics and violence victimization., Results: Almost one-quarter of adolescents with same-sex romantic or sexual partners reported some type of partner violence victimization; about 1 in 10 reported physical victimization. Significant sex differences were found (OR = .29, CI = 0.08, 1.00), with males being less likely than females to report "any violence." Of six other sociodemographic characteristics examined, importance of religion (OR = .27, CI = 0.07-1.07) and school size (OR = .32, CI = 0.09-1.11) were associated with victimization at the p < .10 level. Adolescents who reported that religion was important to them and adolescents who attended larger schools were at lower risk of "any violence.", Conclusions: As with opposite-sex relationships, psychological and minor physical violence victimization is common among adolescents involved in same-sex intimate relationships. Males reporting exclusively same-sex relationships were less likely than females to report experiencing the violence behaviors examined.

A range of new factors is responsible for the current problem with insufficient retirement resources. Changes inside and outside the organization share partial responsibility, as do employee behaviors. In addition, other factors simply have been overlooked as employers and employees think about retirement income adequacy. The authors describe the current situation, discuss the significant risks it creates for both employers and employees and advise employers on what they should do to help employees build a more secure future in retirement.

Employees who are following conventional retirement-planning advice will be in for a rude awakening as they approach retirement and discover that they can't afford to retire just yet or are likely to outlive their retirement funds. The article discusses how we have arrived at this point, what the implications are, and what both employers and employees can do to remedy the situation.

While the mixed model approach to cluster randomization trials is relatively well developed, there has been less attention given to the design and analysis of population-averaged models for randomized and non-randomized cluster trials. We provide novel implementations of familiar methods to meet these needs. A design strategy that selects matching control communities based upon propensity scores, a statistical analysis plan for dichotomous outcomes based upon generalized estimating equations (GEE) with a design-based working correlation matrix, and new sample size formulae are applied to a large non-randomized study to reduce underage drinking. The statistical power calculations, based upon Wald tests for summary statistics, are special cases of a general power method for GEE., (Copyright 2003 John Wiley & Sons, Ltd.)

Objectives: This report examines (1) the prevalence of psychological and minor physical violence victimization in a nationally representative sample of adolescents and (2) associations between sociodemographic factors and victimization., Methods: Analyses are based on 7500 adolescents who reported exclusively heterosexual romantic relationships in the National Longitudinal Study of Adolescent Health. Items from the Conflict Tactics Scale were used to measure victimization. Associations between victimization patterns and sociodemographic characteristics were assessed with polytomous logistic regression., Results: One third of adolescents reported some type of victimization, and 12% reported physical violence victimization. Although most sociodemographic characteristics were significantly associated with victimization, patterns varied by sex and type of victimization., Conclusions: Psychological and minor physical violence victimization is common in opposite-sex romantic relationships during adolescence. The sex-specific associations between sociodemographic characteristics and patterns of partner violence victimization underscore the importance of pursuing longitudinal, theory-driven investigations of the characteristics and developmental histories of both partners in a couple to advance understanding of this public health problem.