Toward Rigorous Idiographic Research in Prevention Science: Comparison Between Three Analytic Strategies for Testing Preventive Intervention in Very Small Samples

Psychosocial prevention research lacks evidence from intensive within-person lines of research to understand idiographic processes related to development and response to intervention. Such data could be used to fill gaps in the literature and expand the study design options for prevention researchers, including lower-cost yet rigorous studies (e.g., for program evaluations), pilot studies, designs to test programs for low prevalence outcomes, selective/indicated/ adaptive intervention research, and understanding of differential response to programs. This study compared three competing analytic strategies designed for this type of research: autoregressive moving average, mixed model trajectory analysis, and P-technique. Illustrative time series data were from a pilot study of an intervention for nursing home residents with diabetes (N=4) designed to improve control of blood glucose. A within-person, intermittent baseline design was used. Intervention effects were detected using each strategy for the aggregated sample and for individual patients. The P-technique model most closely replicated observed glucose levels. ARIMA and P-technique models were most similar in terms of estimated intervention effects and modeled glucose levels. However, ARIMA and P-technique also were more sensitive to missing data, outliers and number of observations. Statistical testing suggested that results generalize both to other persons as well as to idiographic, longitudinal processes. This study demonstrated the potential contributions of idiographic research in prevention science as well as the need for simulation studies to delineate the research circumstances when each analytic approach is optimal for deriving the correct parameter estimates

Real longitudinal data analysis for real people: Building a good enough mixed model

Mixed effect models have become very popular, especially for the analysis of longitudinal data. One challenge is how to build a good enough mixed effects model. In this paper, we suggest a systematic strategy for addressing this challenge and introduce easily implemented practical advice to build mixed effect models. A general discussion of scientific strategies motivates the recommended five step procedure for model fitting. The need to model both the mean structure (the fixed effects) and the covariance structure (the random effects and residual error) creates the fundamental flexibility and complexity. Some very practical recommendations help conquer the complexity. Centering, scaling, and full-rank coding all predictor variables radically improves the chances of convergence, computing speed, and numerical accuracy. Applying computational and assumption diagnostics from univariate linear models to mixed model data greatly helps detect and solve related computational problems. Applying computational and assumption diagnostics from univariate linear models to mixed model data can radically improve the chances of convergence, computing speed, and numerical accuracy. The approach helps fit more general covariance models, a crucial step in selecting a credible covariance model needed for defensible inference. A detailed demonstration of the recommended strategy is based on data from a published study of a randomized trial of a multicomponent intervention to prevent young adolescents' alcohol use. The discussion highlights a need for additional covariance and inference tools for mixed models. The discussion also highlights the need for improving how scientists and statisticians teach and review the process of finding a good enough mixed model

Prospective association between dieting and smoking initiation among adolescents

To examine the relation between dieting and smoking initiation among adolescents. Prospective data from a nationally representative study were used. Two waves (1994 to 1996) of the National Longitudinal Study of Adolescent Health. The sample included 7795 non-Latino Caucasian and non-Latino African-American adolescents. Dieting status was the independent variable and trying smoking and initiation of regular smoking were the dependent variables. Covariates included age, ethnicity, overweight status, false self-perception about being overweight, and availability of cigarettes at home. Logistic regression and latent transition analyses were used. Females had a higher prevalence of dieting (55%) when compared with males (25%). Dieting initiation was a significant predictor for initiation of regular smoking among females (OR = 1.94, p = .010), but not among males. Inactive dieting was a significant predictor among males (OR = 1.74, p = .031), but not among females. Compared to nondieters, initiating and consistent female dieters reported a higher probability of transitioning to having tried regular smoking, although results from logistic regression suggested that the association between consistent dieting and initiation of regular smoking was not significant. There is a positive relation between initiating dieting and initiating regular smoking among females, but among males it is the inactive dieters who show a positive relationship. Results illustrate the importance of examining the association between dieting and the initiation of regular smoking

Risk and Protective Factors for Trajectories of Violent Delinquency Among a Nationally Representative Sample of Early Adolescents

To estimate trajectories of violence using a longitudinal sample of adolescents, considering the effects of multiple domains of influences as differentiators between profiles of violent behavior. A nationally representative sample of 9,421 adolescents ages 15–26. Trajectories were estimated, and multinomial regression procedures were used to evaluate factors predicting membership in high-violence trajectory groups. Mediation analyses were conducted to evaluate the mediated effect of distal influences on violence. Three groups of violence trajectories were identified: (a) nonviolent (73.1%); (b) escalators (14.6%); and (c) desistors (12.3%). Peer alcohol use predicted both escalation and desistance; however, these effects were mediated through individual-level variables. Aside from baseline violence, no other risk factor predicted membership in the “escalator” group. The lack of significance in predicting escalation highlights the need for further study on the etiology of late onset violence. Implications for violence prevention are discussed

A PERSON-CENTERED AND ECOLOGICAL INVESTIGATION OF ACCULTURATION STRATEGIES IN HISPANIC IMMIGRANT YOUTH

Understanding the processes of acculturation in ethnic minority populations is one of the central tasks of crosscultural research. Addressing challenges of theory, methods, and application in acculturation research requires ongoing advancements in methods and theoretical and model development. The current study was designed to explain a person-centered approach to investigating acculturation and biculturalism and to illustrate this method with a sample of 315 Hispanic youth. Pattern analyses of the Hispanicism and Americanism scores from the Bicultural Involvement Scale yielded four distinct acculturation types, including one characterized by moderate scores on both scales. Relations between acculturation types and indicators of individual, family, and peer adaptation were tested. Results indicated that bicultural youth tended to show the most adaptive pattern of functioning across multiple sociocultural domains. Assimilated youth did not show as strongly negative a pattern as has been reported elsewhere. Implications and benefits of a person-centered approach are discussed

Drinking and driving among immigrant and US-born Hispanic young adults: Results from a longitudinal and nationally representative study

To evaluate the risk factors associated with the initiation of driving under the influence (DUI) among Hispanics in a longitudinal and nationally-representative sample of adolescents and young adults. Specifically, this study tests the effect of demographic variables, individual-level risk factors, and eco-processes (e.g., peer drug use, parental involvement) during adolescence on DUI among Hispanic young adults. Data were derived from 1734 Hispanic adolescents surveyed for the National Longitudinal Study of Adolescent Health (Add Health). Survey logistic regression procedures were used to examine the effects of nativity status on DUI initiation, to evaluate the independent effect of each risk factor (demographic, individual-level, and eco-processes), and to identify whether and to what extent these factors are associated with the initiation of DUI. The overall prevalence of DUI initiation was 18.3%. Differences were observed in the rates of DUI initiation by nativity status: first-generation immigrants reported the lowest rates of DUI initiation (15.4%) when compared with second-generation US-born Hispanic youth (17.4%) and third-generation and beyond US-born Hispanic youth (21.5%). US-born Hispanic youth were also more likely to report higher frequency of alcohol use ( t = 3.46, p = 0.001) and marijuana use ( t = 2.34, p = 0.021) compared to immigrant adolescents. After adjusting for a number of risk factors, men (OR = 2.86), marijuana users (OR = 1.98), and those who reported feeling safe in their neighborhoods (OR = 2.02) were at an increased risk DUI initiation. Findings provide support for the “immigrant paradox”: immigrant youth reported lower rates of DUI initiation and other high-risk behaviors when compared with US-born Hispanic youth. ► Rate of DUI initiation differed by nativity status. ► Immigrant youth reported lower rates of DUI behaviors. ► Significant differences were observed among several risk factors by nativity status. ► US-born Hispanic youth engaged in more risky behaviors compared to immigrant youth

Is Violence Bad for Your Health? An Assessment of Chronic Disease Outcomes in a Nationally Representative Sample

Longitudinal offending research has grown substantially in the last two decades. Despite this increased scholarly attention, longitudinal investigations of the effects of offending on physical health have not kept pace. Acknowledging the intersections of criminology, criminal justice, and public health, this study examines the relationship between violent offending and chronic diseases among a nationally representative longitudinal sample of young adults. Results suggest that variation across offender typologies (i.e. adolescence-limited, adult-onset, and consistent violence during youth and young adulthood) significantly predicts experiencing chronic disease in early adulthood, with the risk being the most pronounced among those individuals, who demonstrate violence continuity. Study limitations and policy implications are discussed

Substance Use as a Risk Factor for Intimate Partner Violence Overlap: Generational Differences Among Hispanic Young Adults

Intimate partner violence (IPV) research often focuses on either the victims of IPV or the perpetrators of IPV. Recent studies have documented the existence of a group of victim-perpetrators, for example, they perpetrate IPV and are also the victims of IPV. The current study examines this overlap in IPV perpetration and victimization among a nationally representative, longitudinal sample of 1,488 Hispanics with a focus on generational status. Results from group-based trajectory models and survey multinomial regression techniques suggest that alcohol and marijuana use over time are salient risk factors for IPV perpetration, IPV victimization, and IPV overlap. Study limitations and implications are discussed

Assessing the victim-offender overlap among Puerto Rican youth

Knowledge about offenders and knowledge about victims has traditionally been undertaken without formal consideration of the overlap among the two. A small but growing research agenda has examined the extent of this overlap. At the same time, there has been a minimal amount of research regarding offending and victimization among minority youth, and this is most apparent with respect to Hispanics, who have been increasing in population in the United States. This study explores the joint, longitudinal overlap between offending and victimization among a sample of Puerto Rican youth from the Bronx, New York. Results indicate: (1) an overlap between offending and victimization that persists over time, (2) a considerable overlap in the number, type, direction, and magnitude of the effect of individual, familial, peer, and contextual factors on both offending and victimization, (3) some of the factors related to offending were only relevant at baseline and not for the growth in offending but that several factors were associated with the growth in victimization, and (4) various risk factors could not explain much of the overlap between offending and victimization. Theoretical, policy, and future research directions are addressed. ► Overlap between offending and victimization that persists over time. ► Considerable overlap in the number, type, direction, and magnitude of the effect of individual, familial, peer, and contextual factors on both offending and victimization. ► Some of the factors related to offending were only relevant at baseline and not for the growth in offending but that several factors were associated with the growth in victimization. ► Various risk factors could not explain much of the overlap between offending and victimization