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1.
J Child Psychol Psychiatry ; 59(5): 556-564, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29083026

RESUMO

BACKGROUND: Previous research on peer status of children with attention-deficit/hyperactivity disorder (ADHD) has focused on already-established peer groups, rendering the specific social behaviors that influence peers' initial impressions largely unknown. Recently, theorists have argued that emotion dysregulation is a key aspect of ADHD, with empirical work finding relations between emotion dysregulation and social outcomes. Therefore, the current study focuses on the initial interactions among children varying in ADHD symptoms duringh a novel playgroup, proposing that emotion dysregulation displayed during the playgroup may serve as a possible pathway between ADHD symptoms and peers' initial negative impressions. METHODS: Participants were 233 elementary-age children ranging from 8 to 10 years old (M = 8.83, 70% male). Parents and teachers rated children's ADHD symptoms and related impairment; 51% of the children met criteria for an ADHD diagnosis. Then, children participated with unfamiliar peers in a three-hour playgroup that included three structured and two unstructured tasks. After the tasks, children and staff rated each child on social outcomes. Coders unaware of child's diagnostic status watched videos of the groups and rated each child's global emotion dysregulation during each task. RESULTS: Using multiple raters and methods, ADHD severity was associated with more negative peer ratings, through observed emotion dysregulation. Results were consistent for both parent and teacher ratings of ADHD severity as well as for both peer ratings of likeability and staff ratings of perceived peer likeability. CONCLUSIONS: When focusing on improving peers' initial impressions of children with ADHD symptoms, emotion dysregulation may be a valuable target for intervention.


Assuntos
Sintomas Afetivos/fisiopatologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Relações Interpessoais , Grupo Associado , Desejabilidade Social , Percepção Social , Criança , Feminino , Humanos , Masculino
2.
Multivariate Behav Res ; 51(1): 35-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881956

RESUMO

Regression mixture models are increasingly used as an exploratory approach to identify heterogeneity in the effects of a predictor on an outcome. In this simulation study, we tested the effects of violating an implicit assumption often made in these models; that is, independent variables in the model are not directly related to latent classes. Results indicate that the major risk of failing to model the relationship between predictor and latent class was an increase in the probability of selecting additional latent classes and biased class proportions. In addition, we tested whether regression mixture models can detect a piecewise relationship between a predictor and outcome. Results suggest that these models are able to detect piecewise relations but only when the relationship between the latent class and the predictor is included in model estimation. We illustrate the implications of making this assumption through a reanalysis of applied data examining heterogeneity in the effects of family resources on academic achievement. We compare previous results (which assumed no relation between independent variables and latent class) to the model where this assumption is lifted. Implications and analytic suggestions for conducting regression mixture based on these findings are noted.


Assuntos
Modelos Estatísticos , Análise de Regressão , Criança , Simulação por Computador , Estudos Transversais , Interpretação Estatística de Dados , Escolaridade , Família/psicologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Método de Monte Carlo
3.
Behav Res Methods ; 48(2): 813-26, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26139512

RESUMO

Regression mixture models are a novel approach to modeling the heterogeneous effects of predictors on an outcome. In the model-building process, often residual variances are disregarded and simplifying assumptions are made without thorough examination of the consequences. In this simulation study, we investigated the impact of an equality constraint on the residual variances across latent classes. We examined the consequences of constraining the residual variances on class enumeration (finding the true number of latent classes) and on the parameter estimates, under a number of different simulation conditions meant to reflect the types of heterogeneity likely to exist in applied analyses. The results showed that bias in class enumeration increased as the difference in residual variances between the classes increased. Also, an inappropriate equality constraint on the residual variances greatly impacted on the estimated class sizes and showed the potential to greatly affect the parameter estimates in each class. These results suggest that it is important to make assumptions about residual variances with care and to carefully report what assumptions are made.


Assuntos
Modelos Estatísticos , Método de Monte Carlo , Teorema de Bayes , Simulação por Computador , Humanos , Análise de Regressão
4.
Educ Psychol Meas ; 75(4): 677-714, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26556903

RESUMO

Research increasingly emphasizes understanding differential effects. This paper focuses on understanding regression mixture models, a relatively new statistical methods for assessing differential effects by comparing results to using an interactive term in linear regression. The research questions which each model answers, their formulation, and their assumptions are compared using Monte Carlo simulations and real data analysis. The capabilities of regression mixture models are described and specific issues to be addressed when conducting regression mixtures are proposed. The paper aims to clarify the role that regression mixtures can take in the estimation of differential effects and increase awareness of the benefits and potential pitfalls of this approach. Regression mixture models are shown to be a potentially effective exploratory method for finding differential effects when these effects can be defined by a small number of classes of respondents who share a typical relationship between a predictor and an outcome. It is also shown that the comparison between regression mixture models and interactions becomes substantially more complex as the number of classes increases. It is argued that regression interactions are well suited for direct tests of specific hypotheses about differential effects and regression mixtures provide a useful approach for exploring effect heterogeneity given adequate samples and study design.

5.
Am J Community Psychol ; 54(3-4): 384-96, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25300758

RESUMO

Research has consistently documented the role of environmental risk factors in the onset of delinquent behavior among youth. Less is known about the processes through which these contextual risks are translated to individual youth behavior. The aim of the current study is to examine the role of family risk factors in the transmission of community risk. Data was obtained from a nationally representative sample of over 30,000 middle school youth and community key informants (CKI). A multilevel, moderated mediation model was estimated with family risk as the moderator of the effect of CKI ratings of community risk on youth perceptions of risk. Results showed that when youth came from low risk families (measured by parental use of positive family management strategies), youth perceptions of risk mediated the effects of community risk on youth delinquency; however, there was no evidence of a significant mediated effect under conditions of high risk (measured by poor family management). This appears to be because youth from high-risk families perceived their neighborhoods as high-risk, regardless of actual levels of risk (as reported by CKI). This study finds that the relationship between communities and adolescent behavior is complex and interacts with the family environment.


Assuntos
Delinquência Juvenil/estatística & dados numéricos , Poder Familiar , Características de Residência/estatística & dados numéricos , Risco , Meio Social , Adolescente , Criança , Família , Feminino , Humanos , Masculino , Análise Multinível
6.
Addict Res Theory ; 22(1): 78-89, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24511308

RESUMO

Much of the existing risk factor literature focuses on identifying predictors of low-levels of substance use versus higher-levels of substance use. In this paper, we explore more nuanced patterns of alcohol, tobacco, and other drug (ATOD) use during late adolescence. Our aims were to: 1) identify subgroups of youth with qualitatively different patterns of ATOD use; and 2) explore whether membership among qualitatively distinct, high-risk classes could be predicted based on early adolescent risk factors. Data came from a selected subsample of the National Longitudinal Survey of Youth (n = 1,689). Predictors were measured when youth were about 12 years old; ATOD use was assessed when youth were aged 17 years. Results showed that adolescent ATOD use is not a homogenous behavior. Four distinct classes of adolescent ATOD users were derived. Each class had a qualitatively distinct and discriminable pattern of ATOD use. Ecological predictors were shown to differentiate between latent classes, with peer factors playing a particularly important role in differentiating between high-risk and higher-risk users. Implications for prevention and limitations are discussed.

7.
Multivariate Behav Res ; 48(6): 816-844, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25717214

RESUMO

Regression mixture models have been increasingly applied in the social and behavioral sciences as a method for identifying differential effects of predictors on outcomes. While the typical specification of this approach is sensitive to violations of distributional assumptions, alternative methods for capturing the number of differential effects have been shown to be robust. Yet, there is still a need to better describe differential effects that exist when using regression mixture models. The current study tests a new approach that uses sets of classes (called differential effects sets) to simultaneously model differential effects and account for non-normal error distributions. Monte Carlo simulations are used to examine the performance of the approach. The number of classes needed to represent departures from normality is shown to be dependent on the degree of skew. The use of differential effects sets reduced bias in parameter estimates. Applied analyses demonstrated the implementation of the approach for describing differential effects of parental health problems on adolescent body mass index using differential effects sets approach. Findings support the usefulness of the approach which overcomes the limitations of previous approaches for handling non-normal errors.

8.
PLoS One ; 17(11): e0272204, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36367870

RESUMO

Accruing evidence reveals best practices for how to help individuals living with Sickle Cell Disease (SCD); yet, the implementation of these evidence-based practices in healthcare settings is lacking. The Sickle Cell Disease Implementation Consortium (SCDIC) is a national consortium that uses implementation science to identify and address barriers to care in SCD. The SCDIC seeks to understand how and why patients become unaffiliated from care and determine strategies to identify and connect patients to care. A challenge, however, is the lack of agreed-upon definition for what it means to be unaffiliated and what it means to be a "SCD expert provider". In this study, we conducted a Delphi process to obtain expert consensus on what it means to be an "unaffiliated patient" with SCD and to define an "SCD specialist," as no standard definition is available. Twenty-eight SCD experts participated in three rounds of questions. Consensus was defined as 80% or more of respondents agreeing. Experts reached consensus that an individual with SCD who is unaffiliated from care is "someone who has not been seen by a sickle cell specialist in at least a year." A sickle cell specialist was defined as someone with knowledge and experience in SCD. Having "knowledge" means: being knowledgeable of the 2014 NIH Guidelines, "Evidence-Based Management of SCD", trained in hydroxyurea management and transfusions, trained on screening for organ damage in SCD, trained in pain management and on SCD emergencies, and is aware of psychosocial and cognitive issues in SCD. Experiences that are expected of a SCD specialist include experience working with SCD patients, mentored by a SCD specialist, regular attendance at SCD conferences, and obtains continuing medical education on SCD every 2 years." The results have strong implications for future research, practice, and policy related to SCD by helping to lay a foundation for an new area of research (e.g., to identify subpopulations of unaffiliation and targeted interventions) and policies that support reaffiliation and increase accessibility to quality care.


Assuntos
Anemia Falciforme , Humanos , Consenso , Técnica Delphi , Anemia Falciforme/terapia , Hidroxiureia , Transfusão de Sangue
9.
J Altern Complement Med ; 24(4): 378-384, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29260883

RESUMO

OBJECTIVES: To characterize pediatric chiropractic and assess pediatric quality of life (QoL). DESIGN: A prospective cohort. Setting/Locations: Individual offices within a practice-based research network located throughout the United States. SUBJECTS: A convenience sample of children (8-17 years) under chiropractic care and their parents. EXPOSURE: Chiropractic spinal adjustments and adjunctive therapies. OUTCOME MEASURES: Survey instrument measuring sociodemographic information and correlates from the clinical encounter along with the Patient Reported Outcomes Measurement Information System (PROMIS)-25 to measure QoL (i.e., depression, anxiety, and pain interference). Sociodemographic and clinical correlates were analyzed using descriptive statistics (i.e., frequencies/percentages, means, and standard deviations). The PROMIS-25 data were analyzed using scoring manuals, converting raw scores to T score metric (mean = 50; SD = 10). A generalized linear mixed model was utilized to examine covariates (i.e., sex, number of visits, and motivation for care) that may have played an important role on the PROMIS outcome. RESULTS: The original data set consisted of 915 parent-child dyads. After data cleaning, a total of 881 parents (747 females, 134 males; mean age = 42.03 years) and 881 children (467 females and 414 males; mean age = 12.49 years) comprised this study population. The parents were highly educated and presented their child for mainly wellness care. The mean number of days and patient visits from baseline to comparative QoL measures was 38.12 days and 2.74 (SD = 2.61), respectively. After controlling for the effects of motivation for care, patient visits, duration of complaint, sex, and pain rating, significant differences were observed in the probability of experiencing problems (vs. no reported problems) across all QoL domains (Wald = 82.897, df = 4, p < 0.05). Post hoc comparisons demonstrated the children were less likely to report any symptoms of depression (Wald = 6.1474, df = 1, p < 0.05), anxiety (Wald = 20.603, df = 1, p < 0.05), fatigue (Wald = 22.191, df = 1, p < 0.05), and pain interference (Wald = 47.422, df = 1, p < 0.05) after a trial of chiropractic care. CONCLUSIONS: The QoL of children improved with chiropractic care as measured by PROMIS.


Assuntos
Quiroprática/estatística & dados numéricos , Qualidade de Vida , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pais , Estudos Prospectivos , Resultado do Tratamento
10.
Addict Behav ; 37(3): 299-305, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22136874

RESUMO

BACKGROUND: The relation between early and frequent alcohol use and later difficulties is quite strong. However, the degree that alcohol use persists, which is often a necessary cause for developing alcohol-related problems or an alcohol use disorder, is not well studied, particularly with attention to race and gender. A novel statistical approach, the Multi-facet Longitudinal Model, enables the concurrent study of age of initiation and persistence. METHODS: The models were applied to longitudinal data on youth alcohol use from ages 12 through 19, collected in the (U.S.) National Longitudinal Survey of Youth 1997 cohort (N=8984). RESULTS: Results confirmed that Black adolescents initiate alcohol use at later ages than do White youth. Further, after initiation, White adolescents were substantially more likely than Black adolescents to continue reporting alcohol use in subsequent years. Hispanic teens showed an intermediate pattern. Gender differences were more ambiguous, with a tendency for boys to be less likely to continue drinking after initiation than were girls. CONCLUSIONS: Novel findings from the new analytic models suggest differential implications of early alcohol use by race and gender. Early use of alcohol might be less consequential for males who initiate alcohol use early, Black, and Hispanic youth than for their female and White counterparts.


Assuntos
Comportamento do Adolescente/etnologia , Consumo de Bebidas Alcoólicas/etnologia , Consumo de Bebidas Alcoólicas/epidemiologia , Adolescente , Negro ou Afro-Americano/estatística & dados numéricos , Distribuição por Idade , Fatores Etários , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Estudos Longitudinais , Masculino , Modelos Estatísticos , Grupos Raciais , Assunção de Riscos , Fatores Sexuais , Estados Unidos/epidemiologia , População Branca/estatística & dados numéricos , Adulto Jovem
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