Repeated measures regression mixture models

Regression mixture models are one increasingly utilized approach for developing theories about and exploring the heterogeneity of effects. In this study we aimed to extend the current use of regression mixtures to a repeated regression mixture method when repeated measures, such as diary-type and experience-sampling method, data are available. We hypothesized that additional information borrowed from the repeated measures would improve the model performance, in terms of class enumeration and accuracy of the parameter estimates. We specifically compared three types of model specifications in regression mixtures: (a) traditional single-outcome model; (b) repeated measures models with three, five, and seven measures; and (c) a single-outcome model with the average of seven repeated measures. The results showed that the repeated measures regression mixture models substantially outperformed the traditional and average single-outcome models in class enumeration, with less bias in the parameter estimates. For sample size, whereas prior recommendations have suggested that regression mixtures require samples of well over 1,000 participants, even for classes at a large distance from each other (classes with regression weights of.20 vs.70), the present repeated measures regression mixture models allow for samples as low as 200 participants with an increased number (i.e., seven) of repeated measures. We also demonstrate an application of the proposed repeated measures approach using data from the Sleep Research Project. Implications and limitations of the study are discussed

Health Disparities and the Digital Divide: The Relationship between Communication Inequalities and Quality of Life among Women in a Nationwide Prospective Cohort Study in the United States

Background: Communication inequalities can affect health-seeking behaviors yet the relationship between Internet use and overall health is inconclusive. Communication-related inequalities vary by race/ethnicity and SES but existing research primarily includes middle-class Whites. We therefore examined the relationship between communication-related inequalities—measured by daily Internet use—and health-related quality of life (QOL) using a nationwide prospective cohort study in the United States that consists of primarily low income, minority women. Methods: We examined Internet use and QOL among participants in the Women’s Interagency HIV Study. Data collection occurred from October 2014-September 2015 in Chicago, New York, Washington DC, San Francisco, Atlanta, Chapel Hill, Birmingham/Jackson and Miami. We used multi-variable analyses to examine the relationship between daily Internet use and QOL. Results: The sample of 1,915 women was 73% African American and 15% Hispanic; 53% reported an annual income of ≤$12,000. Women with daily Internet use reported a higher QOL at six months, as did women with at least a high school diploma, income >$12,000, and non-White race; older women and those with reported drug use, depressive symptoms and loneliness had lower QOL. Conclusions: Overcoming communication inequalities may be one pathway through which to improve overall QOL and address public health priorities. Reducing communication-related inequalities—e.g, by providing reliable Internet access—and thus improving access to health promoting information, may lead to improved health outcomes

The influence of health locus of control on the patient-provider relationship

The physician-patient relationship is important to the successful delivery of health care. Health locus of control (HLOC) of the patient, the extent to which individuals attribute their health to their own actions or to external agents, may affect the patient-provider relationship. This study examined the influences of HIV and HLOC on trust in physician among a population of predominantly minority women and their family members. Powerful others HLOC demonstrated a positive relationship with trust in physician and chance HLOC had a negative relationship with trust in physician. HIV moderated both of these relationships

Family mechanisms of structural ecosystems therapy for HIV-seropositive women in drug recovery

OBJECTIVE: Examined the effects of Structural Ecosystems Therapy (SET), a family intervention for women living with HIV or AIDS, compared to a psycho-educational health group (HG) intervention, and reciprocal relationships between women and family members. METHOD: Women (n = 126) and their family members (n = 269) were randomized to one of two conditions and assessed every 4 months for 12 months. Family functioning, drug use, and psychological distress was reported by multiple family members. RESULTS: Multilevel growth curve modeling showed a different family functioning trajectory between SET and HG, B = -0.05, SE = 0.02, p \u3c .01. There was no intervention effect on the trajectory of family-level drug abstinence or psychological distress, but there was a significant difference in the trajectory of psychological distress after controlling for change in family functioning, B = -0.28, SE = 0.13, p \u3c .05. There was an indirect effect from treatment through change in family functioning to change in psychological distress, B = 0.29, SE = 0.12, p \u3c .05. With respect to reciprocal effects, family drug abstinence significantly predicted women\u27s abstinence 4 months later, B = 0.22, SE = 0.06, p \u3c .001. CONCLUSION: Findings demonstrated the interdependence of family members and the impact of family in relapse prevention and partially supported SET\u27s potential for maintaining family functioning and well-being for women living with HIV or AIDS in drug recovery

Efficacy of a Family-Based Intervention for HIV Prevention with Hispanic Adolescents with Same Gender Sexual Behaviors

Despite the availability of efficacious and effective family-based interventions, such interventions are scarce for sexual minority adolescents, particularly among ethnic/racial minorities. Prior to creating an entirely new intervention, a prudent first step may be to determine if existing interventions are efficacious in reducing risk behaviors in sexual minority adolescents. This study assesses the relative efficacy of a general, family-based intervention (Familias Unidas) on improving substance and condom use outcomes among Hispanic adolescents with same gender sexual behaviors (HASGB). Data across five distinct trials of Familias Unidas were synthesized. HASGB were randomized either to an intervention (n = 94) or control condition (n = 100). Mediation analyses tested for intervention efficacy on past 90-day substance (cigarette/alcohol/illicit drug) use and condomless sex at last intercourse in HASGB participants and whether family functioning indicators—parent–adolescent communication, positive parenting, and parental monitoring of peers—mediated the effects. Post hoc analyses explored the moderating role of study target population based on prior risk. Familias Unidas did not impact substance use but significantly reduced condomless sex postintervention relative to the control condition. Hypothesized mediators did not explain this effect. Post hoc analyses indicated that the effect was significant in studies that recruited based on prior risk but not studies that recruited universal samples. Our results suggest that a general, family-based intervention may have positive effects on condom use in HASGB, particularly those with prior indicated risk. Identifying intervention components that drive this effect in addition to developing tailored content for HASGB is needed. © 2021, Society for Prevention Research