Little research has examined factors influencing statistical power to detect the correct number of latent classes using latent profile analysis (LPA). This simulation study examined power related to inter-class distance between latent classes given true number of classes, sample size, and number of indicators. Seven model selection methods were evaluated. None had adequate power to select the correct number of classes with a small (Cohen’s d = .2) or medium (d = .5) degree of separation. With a very large degree of separation (d = 1.5), the Lo-Mendell-Rubin test (LMR), adjusted LMR, bootstrap likelihood-ratio test, BIC, and sample-size adjusted BIC were good at selecting the correct number of classes. However, with a large degree of separation (d = .8), power depended on number of indicators and sample size. The AIC and entropy poorly selected the correct number of classes, regardless of degree of separation, number of indicators, or sample size.

In a three-path mediational model, two mediators intervene in a series between an independent and a dependent variable. Methods of testing for mediation in such a model are generalized from the more often used single-mediator model. Six such methods are introduced and compared in a Monte Carlo study in terms of their Type I error, power, and coverage. Based on its results, the joint significance test is preferred when only a hypothesis test is of interest. The percentile bootstrap and bias-corrected bootstrap are preferred when a confidence interval on the mediated effect is desired, with the latter having more power but also slightly inflated Type I error in some conditions.

This article presents an experimental evaluation of the Family Bereavement Program (FBP), a 2-component group intervention for parentally bereaved children ages 8-16. The program involved separate groups for caregivers, adolescents, and children, which were designed to change potentially modifiable risk and protective factors for bereaved children. The evaluation involved random assignment of 156 families (244 children and adolescents) to the FBP or a self-study condition. Families participated in assessments at pretest, posttest, and 11-month follow-up. Results indicated that the FBP led to improved parenting, coping, and caregiver mental health and to reductions in stressful events at posttest. At follow-up, the FBP led to reduced internalizing and externalizing problems, but only for girls and those who had higher problem scores at baseline.

The authors conducted a cross-sectional and prospective longitudinal study of stress, coping, and psychological symptoms in children of divorce. The sample consisted of 258 children (mean age = 10.1; SD = 1.2), of whom 196 were successfully followed 5.5 months later. A 4-dimensional model of coping was found using confirmatory factor analysis, with the factors being active coping, avoidance, distraction, and support. In the cross-sectional model avoidance coping partially mediated the relations between negative events and symptoms while active coping moderated the relations between negative events and conduct problems. In the longitudinal model significant negative paths were found from active coping and distraction Time 1 to internalizing symptoms Time 2, while Time 1 support coping had a positive path coefficient to Time 2 depression. Positive paths were found between negative events at Time 1 and anxiety at Time 2, and between all symptoms at Time 1 and negative events at Time 2.

This study presents a reanalysis of data from an effective preventive intervention for children from divorced families (S. A. Wolchik et al., 2000) to test mediation of program effects. The study involved 157 children, age 9 -12 years, who were randomly assigned to a parenting program or a literature control condition. Program effects to reduce posttest internalizing problems were mediated through improvement in mother-child relationship quality. Program effects to reduce externalizing problems at posttest and 6 months were mediated through improvement in posttest parental methods of discipline and mother-child relationship quality. The study also describes a new methodology to test mediation of Program ϫ Baseline Status interactions. Analyses demonstrate mediation effects primarily for children who began the program with poorer scores on discipline, mother-child relationship quality, and externalizing problems. Health Grant R01 MH057013-01A1 to evaluate a preventive intervention for children of divorce, and Public Health Service Grant DA09757 for development and application of methods to assess mediation. We thank the mothers and children for their participation as well as the group leaders for their careful and thoughtful delivery of the program.