43 resultados para Structural equation modeling (SEM)
Resumo:
Recent intervention efforts in promoting positive identity in troubled adolescents have begun to draw on the potential for an integration of the self-construction and self-discovery perspectives in conceptualizing identity processes, as well as the integration of quantitative and qualitative data analytic strategies. This study reports an investigation of the Changing Lives Program (CLP), using an Outcome Mediation (OM) evaluation model, an integrated model for evaluating targets of intervention, while theoretically including a Self-Transformative Model of Identity Development (STM), a proposed integration of self-discovery and self-construction identity processes. This study also used a Relational Data Analysis (RDA) integration of quantitative and qualitative analysis strategies and a structural equation modeling approach (SEM), to construct and evaluate the hypothesized OM/STM model. The CLP is a community supported positive youth development intervention, targeting multi-problem youth in alternative high schools in the Miami Dade County Public Schools (M-DCPS). The 259 participants for this study were drawn from the CLP’s archival data file. The model evaluated in this study utilized three indices of core identity processes (1) personal expressiveness, (2) identity conflict resolution, and (3) informational identity style that were conceptualized as mediators of the effects of participation in the CLP on change in two qualitative outcome indices of participants’ sense of self and identity. Findings indicated the model fit the data (χ2 (10) = 3.638, p = .96; RMSEA = .00; CFI = 1.00; WRMR = .299). The pattern of findings supported the utilization of the STM in conceptualizing identity processes and provided support for the OM design. The findings also suggested the need for methods capable of detecting and rendering unique sample specific free response data to increase the likelihood of identifying emergent core developmental research concepts and constructs in studies of intervention/developmental change over time in ways not possible using fixed response methods alone.
Resumo:
Adolescence is a pivotal period offering both opportunities and constraints on individual development. It is during this important time that one decides upon and commits to the values, goals, and beliefs which will form one's identity and guide one throughout the lifespan. Positive youth development programs, such as the Miami Youth Development Project's Changing Lives Program, target the formation of a positive sense of identity as a critical intervention point. Through developing a coherent and positive sense of self, adolescents take control of and responsibility for their lives and their decisions. Furthermore, a positive identity has been found to be a developmental asset and is linked to lower risk behaviors and positive outcomes including increased self-esteem, sense of purpose, and a positive view of the future. Positive youth development programs, which promote positive identity development, have been found to be more strongly tied to positive outcomes including skills, values, and competencies than have contextual opportunities. As such, it is critical to determine what leads to positive identity development. ^ The current study used structural equation modeling to evaluate three potential mediators of identity development. Findings indicated good model fit where change in identity commitment and change in identity exploration were mediated by informational identity style, personal expressiveness, and identity distress. There were also significant differences found between the control and intervention groups indicative of intervention effects. The findings of the current study suggest potential areas of intervention as well as the need for further research including longitudinal study and the use of qualitative methodology. ^
Resumo:
This study examined peer relationships and psychosocial functioning as a function of maternal and paternal involvement and nurturance along with the moderating effects of gender, family form, and ethnicity. Prior research has shown the influence of mother’s involvement on peer relationship quality but not of fathers. Further, previous studies did not examine moderation by family form, gender, or ethnicity. The sample consisted of 1359 students who identified their biological mother and father as the most influential parental figures in their lives. Their ages ranged from 18 to 26; Sixty-one percent of the sample was Hispanic, 13% non-Hispanic Black, 25% non-Hispanic White; 76% female and 70% from intact families. The analytical strategy included using bivariate correlations and structural equation modeling to examine these relationships. ^ All dimensions of maternal and paternal nurturing and involvement were positively related to positive characteristics of peer relationships, self-esteem and life satisfaction consistent with the multicultural findings of PARTheory (Rohner, Khalique, & Cournoyer, 2005). A structural model was developed that was able to adequately account for the relationship between parental influence, peer relationships, and psychosocial functioning. These effects of both maternal and paternal influence were strongly moderated by culture, family form, and gender. Finally, a differential effect was found among parental influence with fathers having a greater influence on friendship quality and importance than mothers, despite greater maternal involvement. ^ These findings have theoretical, clinical, and social implications as they call for a socially based theoretical perspective within which to study these relationships. Such a perspective would better inform clinicians when using impaired social functioning as indicative of axial diagnosis, and for the implementation of social policy to encourage paternal involvement. ^
Resumo:
Despite a considerable progress in developing and testing psychosocial treatments to reduce youth anxiety disorders, much remains to learn about the relation between anxiety symptom reduction and change in youth functional impairment. The specific aims of this dissertation thus were to examine: (1) the relation between different levels of anxiety and youth functional impairment ratings; (2) incremental validity of the Children Global Assessment Scale (CGAS); (3) the mediating role of anxiety symptom reduction on youth functional impairment ratings; (4) the directionality of change between anxiety symptom reduction and youth functional impairment; (5) the moderating effects of youth age, sex, and ethnicity on the mediated relation between youth anxiety symptom reduction and change in functional impairment; and (6) an agreement (or lack thereof) between youths and their parents in their views of change in youth functional impairment vis-à-vis anxiety symptom reduction. ^ The results were analyzed using archival data set acquired from 183 youths and their mothers. Research questions were tested using SPSS and structural equation modeling techniques in Mplus. ^ The results supported the efficacy of psychosocial treatments to reduce the severity of youth anxiety symptoms and its associated functional impairment. Moreover, the results revealed that at posttreatment, youths who scored either low or medium on anxiety levels scored significantly lower on impairment, than youths who scored high on anxiety levels. Incremental validity of the CGAS was also revealed across all assessment points and informants in my sample. In addition, the results indicated the mediating role of anxiety symptom reduction with respect to change in youth functional impairment at posttest, regardless of the youth’s age, sex, and ethnicity. No significant findings were observed with regard to the bidirectionality and an informant disagreement vis-à-vis the relation between anxiety symptom reduction and change in functional impairment. ^ The study’s main contributions and potential implications on theoretical, empirical, and clinical levels are further discussed. The emphasis is on the need to enhance existing evidence-based treatments and develop innovative treatment models that will not only reduce youth’s symptoms (such anxiety) but also evoke genuine and palpable improvements in lives of youths and their families.^
Resumo:
The research goal was to document differences in the epidemiology of prostate cancer among multicultural men [non-Hispanic White (NHW), Hispanic (H), non-Hispanic Black (NHB)], and Black subgroups, particularly among NHB subgroups [US-born (USB) and Caribbean-born (CBB)]. Study findings will be useful in supporting further research into Black subgroups. Aim 1 explored changes over time in reported prostate cancer prevalence, by race/ethnicity and by birthplace (within the Black subgroups). Aim 2 investigated relationships between observed and latent variables. The analytical approaches included confirmatory factor analysis (CFA for measurement models) and structural equation modeling (SEM for regression models). National Center for Health Statistics, National Health Interview Survey (NHIS) data from 1999–2008 were used. The study sample included men aged 18 and older, grouped by race/ethnicity. Among the CBB group, survey respondents were limited to the English-speaking Caribbean. Prostate cancer prevalence, by race showed a higher trend among NHB men than NHW men overall, however differences over time were not significant. CBB men reported a higher proportion of prostate cancer among cancers diagnosed than USB men overall. Due to small sample sizes, stable prostate cancer prevalence trends could not be assessed over time nor could trends in the receipt of a PSA exam among NHB men when stratified by birthplace. USB and CBB men differ significantly in their screening behavior. The effect of SES on PSA screening adjusted for risk factors was statistically significant while latent variable lifestyle was not. Among risk factors, family history of cancer exhibited a consistent positive effect on PSA screening for both USB and CBB men. Among the CBB men, the number of years lived in the US did not significantly affect PSA screening behavior. When NHB men are stratified by birthplace, CBB men had a higher overall prevalence of prostate cancer diagnoses than USB men although not statistically significant. USB men were 2 to 3 times more likely to have had a PSA exam compared to CBB men, but among CBB men birthplace did not make a significant difference in screening behavior. Latent variable SES, but not lifestyle, significantly affected the likelihood of a PSA exam.
Resumo:
Adolescence and emerging adulthood are transition points that offer both opportunities and constraints on individual development. The purpose of this study is threefold: First, to examine two models (i.e., young adolescents in grades 7 and 8 and older adolescents in grade 12) of heavy episodic drinking and examine how heavy episodic drinking affects subsequent educational attainment. By utilizing two different developmental transitions, i.e., middle school to high school and high school to college, it may be possible to better understand the temporal effects of alcohol use and subsequent educational attainment. The second purpose of this study is to examine how alcohol use at Time 1 may lead to the problems in the adolescent's immediate context due to alcohol (i.e., problems with parents, peers, romantic relationships, problems at school) and to examine if these problems affect educational attainment over and above alcohol use alone. The third purpose of this study is to examine the potential gender differences in these models. The study uses data from the National Longitudinal Study of Adolescent Health, which is a large scale, nationally representative school based sample of 20,745 adolescents who were interviewed in grades 7 to 12. Two longitudinal mediational models were evaluated utilizing structural equation modeling. Binge drinking and number of days drunk were used as indicators for a latent variable of heavy episodic drinking (i.e., LHED). In the 7th and 8th grade model, direct effects of LHED were found to predict educational attainment at grade 12. Additionally, in the 7th and 8th grade sample, a mediated relationship was found whereby educational attainment was predicted by problems with parents. Problems with parents were predicted by number of days drunk in the past year. In the 12th grade sample, there were no direct effects or indirect effects of alcohol on educational attainment. This study highlights the need for using a longitudinal framework when examining heavy episodic drinking's effects on educational attainment. ^
Resumo:
The present study pursued two objectives in the context of a randomized clinical trial of cognitive-behavioral therapy with parent (CBT/P) and group (GCBT) involvement. The first objective was to examine the variability in treatment outcome. There were three specific aims within the first objective, to evaluate: (1) youth characteristics (age, depressive, and externalizing disorders) as moderators of treatment outcome; (2) the differential outcome of the treatment approaches as a function of youth characteristics; and (3) the relative efficacy of the treatment approaches at each level of the moderators. ^ The second objective was to evaluate the efficacy of anxiety treatments along secondary depressive symptoms and externalizing behaviors. There were five specific aims within the second objective, to evaluate: (1) whether anxiety treatment yields reductions in secondary problems, (2) the efficacy of anxiety treatments in reducing secondary problems as a function of approach and youth characteristics, (3) whether reductions in anxiety symptoms significantly mediate changes in secondary problems, (4) the directionality of change in the hypothesized mediated relations, and (5) whether the hypothesized mediated relations are moderated by treatment approach and youth characteristics. The specific aims were pursued using data collected from 183 youth and their mothers. Research questions were tested using multiple regressions and structural equation modeling. ^ Age, depressive, and externalizing disorders were significant moderators. CBT/P relative to GCBT lowered anxiety more for younger than older youth. GCBT relative to CBT/P lowered anxiety more for older than younger youth. GCBT relative to CBT/P lowered anxiety more for depressed youth than non-depressed youth. GCBT relative to CBT/P lowered anxiety less for externalizing youth than non-externalizing youth. Treatment reduced depressive symptoms and externalizing problem behaviors. Reductions in anxiety mediated changes in depressive symptoms and externalizing problem behaviors. Reversed directionality was found in the relation between social anxiety and depressive symptoms. In CBT/P the direction of change was from depressive to social anxiety. The opposite was true in GCBT. Reductions in social anxiety mediated posttreatment changes in depressive symptoms in GCBT but not CBT/P. The reverse was true at follow-up. Reductions in social anxiety mediated changes in depressive symptoms for girls but not boys.^
Resumo:
Although the effectiveness of group therapy has been highlighted, the underlying mechanisms involved in the group process have been under studied. The purpose of this study is twofold. First, the current study utilized an outcome mediation model to examine whether initial level of participation in the intervention (Control/No intervention, non-participatory, participatory) predicted change in Identity Conflict Resolution (IDCR), Personal Expressiveness (PE) and Informational Identity Style (INFO) at posttest, and Internalizing (INT) and Externalizing (EXT) behaviors at post and follow-up assessment. Secondly, the current study examined whether relationships between variables varied as a result of group differences in initial participation. The study utilized an archival sample of 234 high school students, ages 14 to 18, who participated in the Changing Lives Program of the Youth Development Project (YDP) since 2003. Structural equation modeling (SEM) was used to examine differences in direct effects as a result of initial participation on an outcome meditational model. To further analyze this model, SEM was utilized to conduct a multi-group solution to examine whether group differences based on level of initial participation in the variables^
Resumo:
Immigration disrupts an individual's support network; however, the stresses of the immigration process increase the need for social support. The presence of social support becomes essential for immigrant children and adolescents to cope with these important transitional circumstances. Friends are both sources of social support and models for behavior. Furthermore, friendship networks are known to have a significant influence on youths' functioning. Literature suggests that peer relations become more important in adolescence and friend support is related to child and adolescent well-being. Thus, friend relationships may be particularly important for immigrant youths who experience disruption in their friendship networks during the process of migration to another country. In addition to friendship networks and support, friend characteristics also need to be taken into consideration as important factors for immigrant youth adjustment. My study involved analyses of the effects of friend support and friend problem behaviors on emotional and behavioral functioning for elementary, middle, and high school age newly immigrant children and adolescents. ^ Immigrant children and adolescents (N = 503) were interviewed at schools by interviewers fluent in participants' languages. Structural Equation Modeling (SEM) analyses revealed that friend support and friend problem behaviors were related to children's self-esteem and externalizing behaviors. In addition, friend problem behavior alone predicted children's psychological symptoms and depression scores. Furthermore, age/grade was found to be a moderator for the relation between friend problem behavior and immigrant youth behavioral adjustment such that compared to elementary and high school cohorts, middle school youths showed more externalizing behaviors when they had friends performing problem behaviors. ^ Results supported the idea that both friend support and friend behavior are related to newly immigrant youths' emotional and behavioral adjustment. This study informs further research and interventions concerning the development of programs to facilitate immigrant youths' adjustment by revealing friendship factors related to their adaptation.^
Resumo:
The dissertation reports on two studies. The purpose of Study I was to develop and evaluate a measure of cognitive competence (the Critical Problem Solving Skills Scale – Qualitative Extension) using Relational Data Analysis (RDA) with a multi-ethnic, adolescent sample. My study builds on previous work that has been conducted to provide evidence for the reliability and validity of the RDA framework in evaluating youth development programs (Kurtines et al., 2008). Inter-coder percent agreement among the TOC and TCC coders for each of the category levels was moderate to high, with a range of .76 to .94. The Fleiss' kappa across all category levels was from substantial agreement to almost perfect agreement, with a range of .72 to .91. The correlation between the TOC and the TCC demonstrated medium to high correlation, with a range of r(40)=.68, p<.001 to r(40)=.79, p<.001. Study II reports an investigation of a positive youth development program using an Outcome Mediation Cascade (OMC) evaluation model, an integrated model for evaluating the empirical intersection between intervention and developmental processes. The Changing Lives Program (CLP) is a community supported positive youth development intervention implemented in a practice setting as a selective/indicated program for multi-ethnic, multi-problem at risk youth in urban alternative high schools in the Miami Dade County Public Schools (M-DCPS). The 259 participants for this study were drawn from the CLP's archival data file. The study used a structural equation modeling approach to construct and evaluate the hypothesized model. Findings indicated that the hypothesized model fit the data (χ2 (7) = 5.651, p = .83; RMSEA = .00; CFI = 1.00; WRMR = .319). My study built on previous research using the OMC evaluation model (Eichas, 2010), and the findings are consistent with the hypothesis that in addition to having effects on targeted positive outcomes, PYD interventions are likely to have progressive cascading effects on untargeted problem outcomes that operate through effects on positive outcomes.
Resumo:
The adaptation process to a new land can be an arduous transition for families who migrate from their countries in an attempt to evade negative life conditions. Family-based immigration has been the cornerstone of immigration policy for the U.S. However, there has been a relative lack of attention given in immigration studies to the impact of immigration particularly on parents. Furthermore, little is known about their adjustment to their post-migration circumstances, particularly the initial phase of migration, where the psychological impact of immigration tends to be concentrated. It is even rarer that investigators have addressed longitudinally the dynamic process of parents' adaptation to a new ecology, which can shed a great deal of light on its mechanisms. In this dissertation, changes over time in levels of stress, adjustment (affect balance and life satisfaction), and the factors (social support, economic hardship, and discrimination) contributing to stress and adjustment were examined in newly immigrant parents from Argentina, Colombia, Cuba, Haiti, and the West Indies. Moderating effects of gender and country-of-origin were examined as well. This study also aimed to investigate to what extent the contributing factors impacted stress and adjustment, not only concurrently, but also over the first three years of post-migration. Analysis of variance results showed that both affect balance and social support increased whereas life satisfaction decreased over time. There was no significant change in stress, however. Both gender and group effects were also observed. Mothers experienced higher stress whereas fathers experienced higher discrimination. Among groups, Haitians appeared at the greatest risk in terms of stress, discrimination, and economic hardship. A structural equation modeling analysis showed that the relative importance of contributing factors changed over time in the process of immigrants' adaptation. Yet, social support emerged as a powerful protective factor in that its effects carried over time, and discrimination was a primary mediator through which other predictors were related to stress and adjustment. These findings shed light on the "hows and whys" of the immigration-adaptation process, by demonstrating the significance of specific conditions of life change to psychological outcomes as newly immigrant parents adapt to their post-migration ecology.
Resumo:
Within the Stage II program evaluation of the Miami Youth Development Project's (YDP) Changing Lives Program (CLP), this study evaluated CLP intervention effectiveness in promoting positive change in emotion-focused identity exploration (i.e. feelings of personal expressiveness; PE) and a "negative" symptom of identity development (i.e. identity distress; ID) as a first step toward the investigation of a self-transformative model of identity development in adolescent youth. Using structural equation modeling techniques, this study found that participation in the CLP is associated with positive changes in PE (path = .841, p < .002), but not changes in ID. Increase in ID scores was found to be associated with increases in PE (path = .229, p < .002), as well. Intervention effects were not moderated by age/stage, gender, or ethnicity, though differences were found in the degree to which participating subgroups (African-American/Hispanic, male/female, 14-16 years old/17-19 years old) experience change in PE and ID. Findings also suggest that moderate levels of ID may not be deleterious to identity exploration and may be associated with active exploration. ^
Resumo:
This study investigated group processes as potential mediators or moderators of positive development outcome and negative reduction intervention response by evaluating the utility of a group measure modified from a widely known measure of group impact found in the group therapy research literature. Four group processes were of primary interest, (1) Group Impact; (2) Facilitator Impact; (3) Skills Impact; and (4) Exploration Impact as assessed by the Session Evaluation Form (SEF). Outcome measures included the Personally Expressive Activities Questionnaire (PEAQ), Erikson Psycho-Social Index (EPSI) and the Zill Behavior Items, Behavior Problem Index (ZBI (BPI)). The sample consisted of 121 multi-ethnic participants drawn from four alternative high schools from the Miami-Dade County Public School system. Utilizing a Latent Growth Curve Modeling approach with Structural Equation Modeling (SEM) statistics, preliminary analyses were conducted to evaluate the psychometric properties of the SEF and its role in the mediation or moderation of intervention outcome. Preliminary results revealed evidence of a single higher order factor representing a "General" global reaction, which was hypothesized to be a "Positive Group Climate" construct to the program as opposed to the four distinct group processes that were initially hypothesized to affect outcomes. The results of the evaluation of the mediation or moderation role of intervention outcome of the single "General" global latent factor ("Positive Group Climate" construct) did not significantly predict treatment response on any of the outcome variables. Nevertheless, the evidence of an underlying "General" global latent factor ("Positive Group Climate" construct) has important future directions for research on positive youth development programs as well as in group therapy research.
Resumo:
This dissertation comprised of three essays provides justification for the need to pursue research on multinationality and performance with a more fine-grained approach. Essay one is a conceptual response to an article written by Jean-Francois Hennart in 2011 which questions the need and approach toward future research in this domain. I argue that internalization theory does not render multinationality and performance research meaningless and identify key areas where methodological enhancements can be made to strengthen our research findings with regard to Hennart's call for more content validity. Essay two responds to the need for more-fine grained research on the consequences of multinationality by introducing non-traditional measures of performance such as social and environmental performance and adopting a more theoretically relevant construct of regionalization to capture international diversification levels of the firm. Using data from the world's largest 600 firms (based on sales) derived from Bloomberg and the Directory of Corporate Affiliates; I employ general estimating equation analysis to account for the auto-correlated nature of the panel data alongside multivariate regression techniques. Results indicate that regionalization has a positive relationship with economic performance while it has a negative relationship with environmental and social performance outcomes, often referred to as the "Triple Bottom-Line" performance. Essay three builds upon the work in the previous essays by linking the aforementioned performance variables and sample to corporate reputation which has been shown to be a beneficial strategic asset. Using Structural Equation Modeling I explore economic, environmental and social signals as mediators on relationship between regionalization and firm reputation. Results indicate that these variables partially mediate a positive relationship between regionalization and firm reputation. While regionalization positively affects the reputation building signal of economic performance, it aids in reputation building by reducing environmental and social disclosure effects which interestingly impact reputation negatively. In conclusion, the dissertation submits opportunities for future research and contributes to research by demonstrating that regionalization affects performance, but the effect varies in accordance with the performance criterion and context. In some cases, regional diversification may produce competing or conflicting outcomes among the potential strategic objectives of the firm.
Resumo:
Among people living with HIV (PLWH), adherence to antiretroviral therapy (ART) can be affected by problems of neurocognitive (NC) impairment, stress, alcohol and other drug (AOD) abuse, and other barriers. The aims of this research were to: (1) examine factors associated with NC impairment, (2) explore relationships between psychosocial variables with ART adherence and viral load (VL), and (3) evaluate the efficacy of an evidence-based intervention in improving ART adherence, increasing service utilization, and decreasing VL. The first study (n=370) was cross sectional and used structural equation modeling to test whether AOD use, years living with HIV, and time from HIV diagnosis to seeking care were associated with poorer NC functioning. The second study (n=246) used similar methods to test the hypothesis that stress, barriers to adherence, NC impairment, poor social support, and AOD use were related to lower VL mediated by ART adherence. The third study (n=243) evaluated an evidence-based, eight-session program to improve ART adherence, reduce VL, and increase service utilization in a randomized controlled trial. Study participants were PLWH living in South Florida, 18 to 60 years old, with a history of alcohol abuse enrolled from January 2009 through November 2012. Secondary analysis of available data showed: (1) scores on interference with executive functioning increased by 0.32 for each day of marijuana use and 1.18 for each year living with HIV, but no association was found between alcohol use and NC functioning; (2) each barrier to adherence was associated with a 10% decrease in adherence to ART and a 0.42 unit increase in VL (log10) and the relationship between barriers and VL was partially mediated by ART adherence; (3) participants in the evidence-based program were more likely than the comparison group to report an undetectable VL (OR=2.25, p<0.01) at 6 months, but not 3 months, post-intervention. Psychosocial factors affect VL, but ART adherence is essential in achieving an undetectable VL in PLWH.