Biomedical subjects

Daniel J Bauer

Publications and source records attributed to Daniel J Bauer.

10 recordsLinked to original sources

PubMed2007

Sexual behavior and drug use among Asian and Latino adolescents: association with immigrant status.

This paper contributes new evidence on the association between immigrant status and health by describing and attempting to explain patterns of co-occurring sex and drug use behaviors among Asian and Latino adolescents in the United States. Nine patterns of sex and drug use behaviors were identified from a cluster analysis of data from 3,924 Asian and Latino youth (grades 7-12) who participated in the National Longitudinal Study of Adolescent Health (Add Health). The relationship between immigrant status and risk cluster membership was evaluated with multinomial logistic regression. Compared to foreign-born youth, U.S. born Asian and Latino adolescents were more likely to engage in sex and drug risk behaviors. Family and residential characteristics associated with immigrant status partly accounted for this finding. The results indicate that among Asian and Latino adolescents, assimilation to U.S. risk behavior norms occurs rapidly and is evident by the second generation.

Acculturation↗

PubMed2006

Sexual and drug behavior patterns and HIV and STD racial disparities: the need for new directions.

OBJECTIVES: We used nationally representative data to examine whether individuals' sexual and drug behavior patterns account for racial disparities in sexually transmitted disease (STD) and HIV prevalence. METHODS: Data were derived from wave III of the National Longitudinal Study of Adolescent Health. Participants were aged 18 to 26 years old; analyses were limited to non-Hispanic Blacks and Whites. Theory and cluster analyses yielded 16 unique behavior patterns. Bivariate analyses compared STD and HIV prevalences for each behavior pattern, by race. Logistic regression analyses examined within-pattern race effects before and after control for covariates. RESULTS: Unadjusted odds of STD and HIV infection were significantly higher among Blacks than among Whites for 11 of the risk behavior patterns assessed. Across behavior patterns, covariates had little effect on reducing race odds ratios. CONCLUSIONS: White young adults in the United States are at elevated STD and HIV risk when they engage in high-risk behaviors. Black young adults, however, are at high risk even when their behaviors are normative. Factors other than individual risk behaviors and covariates appear to account for racial disparities, indicating the need for population-level interventions.

Adolescent↗

PubMed2006

Local solutions in the estimation of growth mixture models.

Finite mixture models are well known to have poorly behaved likelihood functions featuring singularities and multiple optima. Growth mixture models may suffer from fewer of these problems, potentially benefiting from the structure imposed on the estimated class means and covariances by the specified growth model. As demonstrated here, however, local solutions may still be problematic. Results from an empirical case study and a small Monte Carlo simulation show that failure to thoroughly consider the possible presence of local optima in the estimation of a growth mixture model can sometimes have serious consequences, possibly leading to adoption of an inferior solution that differs in substantively important ways from the actual maximum likelihood solution. Often, the defaults of current software need to be overridden to thoroughly evaluate the parameter space and obtain confidence that the maximum likelihood solution has in fact been obtained.

Adolescent↗

PubMed2006

Conceptualizing and testing random indirect effects and moderated mediation in multilevel models: new procedures and recommendations.

The authors propose new procedures for evaluating direct, indirect, and total effects in multilevel models when all relevant variables are measured at Level 1 and all effects are random. Formulas are provided for the mean and variance of the indirect and total effects and for the sampling variances of the average indirect and total effects. Simulations show that the estimates are unbiased under most conditions. Confidence intervals based on a normal approximation or a simulated sampling distribution perform well when the random effects are normally distributed but less so when they are nonnormally distributed. These methods are further developed to address hypotheses of moderated mediation in the multilevel context. An example demonstrates the feasibility and usefulness of the proposed methods.

Adolescent↗

PubMed2005

The role of nonlinear factor-to-indicator relationships in tests of measurement equivalence.

Measurement invariance is a necessary condition for the evaluation of factor mean differences over groups or time. This article considers the potential problems that can arise for tests of measurement invariance when the true factor-to-indicator relationship is nonlinear (quadratic) and invariant but the linear factor model is nevertheless applied. The factor loadings and indicator intercepts of the linear model will diverge across groups as the factor mean difference increases. Power analyses show that even apparently small quadratic effects can result in rejection of measurement invariance at moderate sample sizes when the factor mean difference is medium to large. Recommendations include the identification of nonlinear relationships using diagnostic plots and consideration of newly developed methods for fitting nonlinear factor models.

Analysis of Variance↗

PubMed2004

Developmental properties of transactional models: the case of life events and mastery from adolescence to young adulthood.

That behavior reflects ongoing transactions between person and context is an enshrined proposition of developmental theory, although the dynamic properties of these transactions have not been fully appreciated. In this article, we focus on reciprocal links between the Pearlin mastery scale and life events in the transition to adulthood, a strategic relationship given that control orientations are thought to mediate links between stressors and a range of indicators of distress, and given that life events become increasingly likely in young adulthood. Drawing on 12 waves of data from the Youth Development Study, spanning ages 14-15 to 26-27, we examine a series of growth curve models that interrelate mastery and life events. Results for females reveal that mastery during the senior year of high school predicts life events for the following 4-year period, which in turn predicts mastery over the 5-year period spanning ages 21-22 to 26-27. For males, mastery during the senior year (and perhaps the sophomore year) predicts subsequent life events, which in turn have short-term implications for mastery. Thus, transactions between life events and mastery are observed, although the temporal patterns of these exchanges are complex. These findings are discussed in terms of the developmental properties of transactions between person and context.

Adolescent↗

PubMed2004

The integration of continuous and discrete latent variable models: potential problems and promising opportunities.

Structural equation mixture modeling (SEMM) integrates continuous and discrete latent variable models. Drawing on prior research on the relationships between continuous and discrete latent variable models, the authors identify 3 conditions that may lead to the estimation of spurious latent classes in SEMM: misspecification of the structural model, nonnormal continuous measures, and nonlinear relationships among observed and/or latent variables. When the objective of a SEMM analysis is the identification of latent classes, these conditions should be considered as alternative hypotheses and results should be interpreted cautiously. However, armed with greater knowledge about the estimation of SEMMs in practice, researchers can exploit the flexibility of the model to gain a fuller understanding of the phenomenon under study.

Factor Analysis, Statistical↗

PubMed2004

Testing main effects and interactions in latent curve analysis.

A key strength of latent curve analysis (LCA) is the ability to model individual variability in rates of change as a function of 1 or more explanatory variables. The measurement of time plays a critical role because the explanatory variables multiplicatively interact with time in the prediction of the repeated measures. However, this interaction is not typically capitalized on in LCA because the measure of time is rather subtly incorporated via the factor loading matrix. The authors' goal is to demonstrate both analytically and empirically that classic techniques for probing interactions in multiple regression can be generalized to LCA. A worked example is presented, and the use of these techniques is recommended whenever estimating conditional LCAs in practice.

Humans↗

PubMed2003

Distributional assumptions of growth mixture models: implications for overextraction of latent trajectory classes.

Growth mixture models are often used to determine if subgroups exist within the population that follow qualitatively distinct developmental trajectories. However, statistical theory developed for finite normal mixture models suggests that latent trajectory classes can be estimated even in the absence of population heterogeneity if the distribution of the repeated measures is nonnormal. By drawing on this theory, this article demonstrates that multiple trajectory classes can be estimated and appear optimal for nonnormal data even when only 1 group exists in the population. Further, the within-class parameter estimates obtained from these models are largely uninterpretable. Significant predictive relationships may be obscured or spurious relationships identified. The implications of these results for applied research are highlighted, and future directions for quantitative developments are suggested.

Group Processes↗

PubMedDate not supplied

Implications of racial and gender differences in patterns of adolescent risk behavior for HIV and other sexually transmitted diseases.

CONTEXT: Sexual and substance use behaviors covary in adolescence. Prevalence of HIV and other sexually transmitted diseases (STDs) differs according to race and gender, yet few studies have systematically investigated risk behavior patterns by subgroup, particularly with nationally representative data. METHODS: A priori considerations and K-means cluster analysis were used to group 13,998 non-Hispanic black and white participants in the National Longitudinal Study of Adolescent Health, Wave 1, according to self-reported substance use and sexual behavior. Multinomial logit analyses examined racial and gender differences by cluster. RESULTS: Among 16 clusters, the two defined by the lowest risk behaviors (sexual abstinence and little or no substance use) comprised 47% of adolescents; fewer than 1% in these groups reported ever having received an STD diagnosis. The next largest cluster-characterized by sexual activity (on average, with one lifetime partner) and infrequent substance use-contained 15% of participants but nearly one-third of adolescent with STDs. Blacks were more likely than whites to be in this group. Black males also were more likely than white males to be in three small clusters characterized by high-risk sexual behaviors (i.e., having had sex with a male or with at least 14 partners, or for drugs or money). Black females generally were the least likely to be in high-risk behavior clusters but the most likely to report STDs. CONCLUSIONS: Adolescents' risk behavior patterns vary by race and gender, and do not necessarily correlate with their STD prevalence. Further investigation of adolescents' partners and sexual networks is needed.

Adolescent↗