Navegando por Palavras-chave "Bifactor model"
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- ItemSomente MetadadadosAttention-deficit/hyperactivity disorder dimensionality: the reliable 'g' and the elusive 's' dimensions(Springer, 2016) Wagner, Flavia; Martel, Michelle M.; Cogo-Moreira, Hugo [UNIFESP]; Moreira Maia, Carlos Renato; Pan, Pedro Mario [UNIFESP]; Rohde, Luis Augusto; Salum, Giovanni AbrahaoThe best structural model for attention-deficit/hyperactivity disorder (ADHD) symptoms remains a matter of debate. The objective of this study is to test the fit and factor reliability of competing models of the dimensional structure of ADHD symptoms in a sample of randomly selected and high-risk children and pre-adolescents from Brazil. Our sample comprised 2512 children aged 6-12 years from 57 schools in Brazil. The ADHD symptoms were assessed using parent report on the development and well-being assessment (DAWBA). Fit indexes from confirmatory factor analysis were used to test unidimensional, correlated, and bifactor models of ADHD, the latter including "g" ADHD and "s" symptom domain factors. Reliability of all models was measured with omega coefficients. A bifactor model with one general factor and three specific factors (inattention, hyperactivity, impulsivity) exhibited the best fit to the data, according to fit indices, as well as the most consistent factor loadings. However, based on omega reliability statistics, the specific inattention, hyperactivity, and impulsivity dimensions provided very little reliable information after accounting for the reliable general ADHD factor. Our study presents some psychometric evidence that ADHD specific ("s") factors might be unreliable after taking common ("g" factor) variance into account. These results are in accordance with the lack of longitudinal stability among subtypes, the absence of dimension-specific molecular genetic findings and non-specific effects of treatment strategies. Therefore, researchers and clinicians might most effectively rely on the "g" ADHD to characterize ADHD dimensional phenotype, based on currently available symptom items.
- ItemSomente MetadadadosAttention-deficit/hyperactivity disorder dimensionality: the reliable 'g' and the elusive 's' dimensions(Springer, 2016) Wagner, Flavia; Martel, Michelle M.; Cogo-Moreira, Hugo [UNIFESP]; Moreira Maia, Carlos Renato; Pan, Pedro Mario [UNIFESP]; Rohde, Luis Augusto; Salum, Giovanni AbrahaoThe best structural model for attention-deficit/hyperactivity disorder (ADHD) symptoms remains a matter of debate. The objective of this study is to test the fit and factor reliability of competing models of the dimensional structure of ADHD symptoms in a sample of randomly selected and high-risk children and pre-adolescents from Brazil. Our sample comprised 2512 children aged 6-12 years from 57 schools in Brazil. The ADHD symptoms were assessed using parent report on the development and well-being assessment (DAWBA). Fit indexes from confirmatory factor analysis were used to test unidimensional, correlated, and bifactor models of ADHD, the latter including "g" ADHD and "s" symptom domain factors. Reliability of all models was measured with omega coefficients. A bifactor model with one general factor and three specific factors (inattention, hyperactivity, impulsivity) exhibited the best fit to the data, according to fit indices, as well as the most consistent factor loadings. However, based on omega reliability statistics, the specific inattention, hyperactivity, and impulsivity dimensions provided very little reliable information after accounting for the reliable general ADHD factor. Our study presents some psychometric evidence that ADHD specific ("s") factors might be unreliable after taking common ("g" factor) variance into account. These results are in accordance with the lack of longitudinal stability among subtypes, the absence of dimension-specific molecular genetic findings and non-specific effects of treatment strategies. Therefore, researchers and clinicians might most effectively rely on the "g" ADHD to characterize ADHD dimensional phenotype, based on currently available symptom items.
- ItemSomente MetadadadosValidity of the Center for Epidemiological Studies Depression scale in Type 2 diabetes(Pergamon-Elsevier Science Ltd, 2016) Carter, Jasmine; Cogo-Moreira, Hugo [UNIFESP]; Herrmann, Nathan; Merino, Daniel; Yang, Pearl; Shah, Baiju R.; Kiss, Alex; Reitav, Jaan; Oh, Paul I.; Swardfager, WalterObjective: Depressive symptoms are common among people with Type 2 diabetes mellitus (T2DM). This study aimed to validate the 3-factor structure of the 14-item Center for Epidemiological Studies Depression (CES-D) scale proposed by Carleton et al. (2013) in a T2DM population. Methods: The CES-D was administered to consecutive patients with T2DM entering a rehabilitation program. Construct validity was assessed using confirmatory factor analysis. Subscale viability, differential item functioning, and associations with clinical characteristics were tested in bifactor models. Results: Among adults with T2DM (n = 305, age 56.9 +/- 11.1, 44.9% male, duration of diabetes 7.8 +/- 7.9 years, HbA1c 0.076 +/- 0.014%), the construct validity of Carleton's 3-factor solution (negative affective, positive affective and somatic symptoms) was confirmed, although negative affective and somatic symptoms were highly correlated (r = 0.926). The CES-D items can be summed to arrive at a total score (omega(H) = 0.869), but not subscale scores (omega(s) > 0.7). Differential item functioning was not found based on age or body mass index (BMI), but Item 1 ("I was bothered by things that don't usually bother me") was inflated in women and Item 7 ("I felt that everything I did was an effort") was inflated in those with higher glycosylated haemoglobin (HbA1c). The general depression factor decreased with age (beta = 0.247, p < 0.001) and increased with BMI (beta= 0.102, p = 0.041) but not HbA1 c (beta= 0.065, p = 0.461). Negative affective symptoms (beta = 0.743, p = 0.001), but not other depressive symptoms, were higher in women. Conclusions: The 14-item CES-D retained construct validity in adults with T2DM. Depressive symptoms were associated with younger age, female gender and BMI, but not with glycemic control. (C) 2016 Elsevier Inc. All rights reserved.