Jacob Arie Laros

Modelos de equações estruturais em psicologia: conceitos e aplicações

The debate concerning procedures and techniques of data treatment is relevant in the context of production and progress of knowledge in a broad range of subject areas. In the past decade, a framework of data treatment methods denominated Structural Equation Modeling received a great deal of attention from researchers. This data treatment procedure has its historical origins related to different areas of knowledge like biometrics, econometrics and psychometrics. As a consequence of its unique characteristics, scientific report in Structural Equation Modeling should consider various relevant aspects, like the theoretical definition of the model to be tested, the specification and identification of the model, as well as estimation and measurement aspects of the adequation indices. Several of these elements are presented and discussed in the present article, focusing on the possibilities of practical application in the field of Psychology and related sciences. In addition, future perspectives and limitations of Structural Equation Modeling are also discussed.

Validação cruzada de uma escala de clima organizacional

Cross validation of a scale of organizational climate. The stability of the factor structure of a scale of organizational climate of 66 items was investigated. A sample of 61,349 respondents was randomly divided in two parts, the first to identify the factor structure, the second to verify its replicability. The criterion used to identify the number of factors resulted in the retention of seven factors. To obtain a satisfactory factor structure 23 items were excluded. A second factor analysis of the remaining 43 items indicated seven factors explaining 63.4% of the variance. Second-order factor analysis revealed one general factor accounting for 55.5% of the variance. To investigate the stability of the factor structure the same procedures and criteria were used with the second sample. The results indicate a high stability of the hierarchical factor structure of the scale of organizational climate consisting of seven first-order factors and one general second-order factor.

Termômetro de Distress: validação de um instrumento breve para avaliação diagnóstica de pacientes oncológicos

The specialized literature provides instruments measuring stress for general application. Those instruments have been employed in occupational and health contexts. But since 1997, the National Comprehensive Cancer Network (NCCN) recommends the adoption of a specific measuring instrument for the assessment of cancer patients. Considering the existence of clinical and scientific interest to develop future meta-analysis studies in the field of Oncology, which will include Brazilian samples, the adaptation and validation of the Distress Thermometer (TD) was undertaken. The effectiveness of the TD in assessing distress was verified by comparison with the Anxiety and Depression Scale (HAD), a clinically established tool for evaluating distress. In order to that, a sample of 83 patients answered the TD and the HAD. The data were analyzed using SPSS 15.0. Results of the analysis indicated 82% for sensitivity and 98% for specificity. Using the TD appeared feasible and effective for psychological distress screening.

Cultural bias in the SON-R test: comparative study of Brazilian and dutch children

The present study, including 83 Brazilian and 51 Dutch children, evaluated the presence of cultural bias in items of the SON-R 5½-17 that make use of concrete objects and situations. Two procedures were followed to detect item bias. The first consisted of asking the children, immediately after an incorrect answer, whether they recognized the pictures. The second procedure compared item difficulties of the Brazilian children with those of the Dutch children belonging to the standardization sample of the SON-R 5½-17. Fourteen items were detected with bias: ten of these favored the Dutch group and four the Brazilian group. The cultural disadvantage for Brazilian children is rather small, taking the large amount of investigated items into account. This study indicated which items of the SON-R 5½-17 should be improved, not only for reasons of cultural bias, but also because children, irrespective of their cultural background, encountered problems with the recognition of several pictures.

Fatores associados ao desempenho escolar: estudo multinível com dados do SAEB/2001

The purpose of this study was to construct a model of student performance using multilevel analysis, a type of multiple regression that takes into consideration the hierarchical structure of the data. The study used the data of the third grade students of secondary school who participated in the SAEB 2001 assessment. After controlling the effect of the variables of selectivity and school composition, an intraclass correlation of 0.17 was found, indicating that 17% of the variance in student performance can be attributed to the school level. In the final multilevel model seven variables of student level and nine variables of school level were included. The variables with the strongest effect on student level were: school delay and comparison of the student with his colleagues. On school level these variables were: aggregated cultural resources and aggregated school delay. The final model elaborated in this study will hopefully be used to elaborate public policies with a view to improve the Brazilian educational system.

Manejo de estresse ocupacional na perspectiva da área de avaliação de programas

Occupational stress management from the perspective of the area of program evaluation. The aim of this article is to present procedures to implement and evaluate individual focused occupational stress management interventions, based on literature of the area of occupational health psychology and program evaluation. Intervention, implementation and evaluation planning are discussed, based on the social science research cycle, which stages include needs evaluation, search of theoretical basis, definition of goals, variables, instruments, design, participants, procedures, program implementation and data collection, analysis and results interpretation, publishing results and formulation of new questions. Future perspectives for program evaluation and possible gains resulted from the alliance between this area and occupational stress management interventions are discussed.

Análise multinível: contribuições para estudos sobre efeito do contexto social no comportamento individual

The recognition of the influence of social context on human behavior emphasizes the need for models that allow for the identification of this effect. The theoretical and technical characteristics of multilevel models are presented here, since they satisfy this requirement. From a theoretical perspective, it is worthwhile highlighting that the choice of a multilevel model should be founded, as much as possible, on a multilevel theory that points to the predictive role of variables originating from different levels. The construction of multilevel models guided by theory will result in more fruitful models with higher external validity in comparison with models built with little or no theoretical foundations. From a technical perspective, it may be stated that multilevel analysis shows a high degree of similarity with traditional linear regression including many of its presuppositions. This study enables us to conclude that multilevel analysis is an appropriate tool for researchers interested in the identification of the effects of social context on human behavior.

Avaliação de ansiedade e depressão em pacientes oncológicos: comparação psicométrica

Evaluation tools of anxiety and depression are useful for diagnosis and clinical management orientation before the changes caused by cancer experiences. The present study compared psychometric advantages and disadvantages of instruments commonly used in specialized services in Oncology: Hospital Anxiety and Depression Scale (HADS), General Anxiety Disorder (GAD-7) and the Patient Health Questionnaire (PHQ-9). There were 200 patients diagnosed with cancer and in chemotherapy treatment participating in the study, being 30.5% men and 69.5% women, aged between 18 to 89 years (M=56.8; SD=15). The instruments showed coefficients of reliability varying between .74 and .84. The evaluated psychometric characteristics indicated better values for HADS-D and GAD-7. However, HADS-A and PHQ-9 were also found to be suitable for evaluation of anxiety and depression. We suggest the adoption of these instruments for screening, diagnosis and monitoring of cancer patients, especially in psychological and social domains.

Fatores associados ao desempenho escolar em Português: um estudo multinível por regiões

The purpose of the present study was to identify which characteristics of students and schools affect proficiency in Portuguese Language, as well as to verify the existence of differences between Brazilian regions in this respect. The data were analyzed of 33,962 third grade students nessed in 1,661 secondary schools who participated in the 2001 assessment of the SAEB. Among the control variables, socioeconomic status of the school had the strongest contribution to the final model. At least 41% of the school level variance and 14% of the student level variance were explained in the final multilevel model. It can be concluded that the inequality between Brazilian regions in relation to the performance of schools in Portuguese Language is strongly related to the socioeconomic status of the students of the schools.Resumo No presente estudo objetivou-se identificar quais características de alunos e escolas são associadas ao desempenho em Português, bem como verificar se existem diferenças entre as regiões geográficas brasileiras. Foram analisados os dados de 33.962 alunos da 3a série do Ensino Médio, distribuídos em 1.661 escolas brasileiras pesquisadas no SAEB/2001. Entre as variáveis de controle, a maior contribuição para o modelo final foi da variável nível socioeconômico da escola. Pelo menos 41% da variância do nível da escola e 14% da variância do nível do aluno foram explicados no modelo multinível final. Concluí-se que a desigualdade entre regiões do Brasil em relação ao desempenho médio das escolas em Língua Portuguesa, é fortemente relacionada com o nível socioeconômico dos alunos e das escolas. Palavras-chave: Desempenho escolar. Regressão. Análise multinível. Região geográfica.

Testing the difficulty theory of the SON-R 512 –17, a non-verbal test of intelligence

Fischers (1973) linear logistic test model can be used to test hypotheses regarding the effect of covariates on item difficulty and to predict the difficulty of newly constructed test items. However, its assumptions of equal discriminatory power across items and a perfect prediction of item difficulty are never absolutely met. The amount of misfit in an application of a Bayesian version of the model to two subtests of the SON-R 5(1/2)-17 is investigated by means of item fit statistics in the framework of posterior predictive checks and by means of a comparison with a model that allows for residual (co)variance in the item parameters. The effect of the degree of residual (co)variance on the robustness of inferences is investigated in a simulation study.