Navegando por Palavras-chave "Confirmatory factor analysis"

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    Attention-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 Abrahao
    The 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.
  • Nenhuma Miniatura disponível
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    Somente Metadadados
    Attention-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 Abrahao
    The 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.
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    A schizophrenia-like behavioral trait in the SHR model: Applying confirmatory factor analysis as a new statistical tool
    (Pergamon-Elsevier Science Ltd, 2018) Peres, Fernanda Fiel [UNIFESP]; Eufrasio, Rai Alvares [UNIFESP]; Gouvea, Douglas Albuquerque [UNIFESP]; Dian, Mariana Cepollaro [UNIFESP]; Santos, Camila Mauricio [UNIFESP]; Swardfager, Walter; Abilio, Vanessa Costhek [UNIFESP]; Cogo-Moreira, Hugo [UNIFESP]
    Questionnaires that assess symptoms of schizophrenia patients undergo strict statistical validation, often using confirmatory factor analysis (CFA). CFA allows testing the existence of a trait that both collectively explains the symptoms and gathers the information in a single general index. In rodents, some behaviors are used to model psychiatric symptoms, but no single test or paradigm adequately captures the disorder's phenotype in toto. This work investigated the existence of a behavioral trait in the SHR strain underlying five behavioral tasks used in schizophrenia animal studies and altered in this strain: locomotor activity, rearing behavior, social interaction, prepulse inhibition of startle and contextual fear conditioning. The analysis was conducted on a sample of Wistar (n= 290) and Spontaneously Hypertensive Rats (SHRs, n= 290). CFA showed the existence of a continuous trait in both strains, and higher values among SHRs. This work is the first to demonstrate the existence of a schizophrenia-like trait in an animal model. We suggest that using CFA to evaluate behavioral parameters in animals might facilitate the pre-clinical investigation of psychiatric disorders, diminishing the gap between animal and human studies.