Modelos inflacionados de zeros: aplicações na análise de um questionário de frequencia alimentar

• Autor(a) principal: Fumes, Giovana [UNESP]
• Data de Publicação: 2010
• Outros Autores: Corrente, José Eduardo [UNESP]
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://jaguar.fcav.unesp.br/RME/fasciculos/v28/v28_n1/indice_v28_n1.php; http://hdl.handle.net/11449/140334
• topic: Negative binomial distribution; Poisson distribution; Zero-inflated distribution; Food frequency questionnaire; Overdispersion; Distribuição binomial negativa; Distribuição de Poisson; |Distribuição inflacionada de zero; Questionário de frequência alimentar; Superdispersão

This study aimed at using zero-inflated models to analyze a food frequency questionnaire (F.F.Q.) applied to elderly individuals from a medium-sized city in inner São P aulo state, investigating the models that can be best fitted to the data according to the percent of zeros found and the factors influencing both intake and non-intake of certain food types. The response variable used was the monthly intake frequency of foods from the F.F.Q., and the associated co-variates were related to socio-demographic characteristics concerning prevention and reported morbidities. The Poisson, Negative Binomial, Zero-Inflated Poisson and Zero-Inflated Negati e Binomial models were used. For a data set with up to 10% of zeros, the usual Negative Binomial model showed to be adequate. Due to data amplitude, the inflated models show ed to b e adequate only at the p ercentage of 1 0 % to 5 0 % of zeros. It was also shown that the probability of consumption of the selected food types was associated with gender, nutritional status, medication use and physical activity practice. The probability of non-consumption was observed in association with gender, bow el functioning and daily water consumption .