OBJECTIVE To analyze the prevalence of individuals at risk of dependence and its associated factors. METHODS The study was based on data from the Catalan Health Survey, Spain conducted in 2010 and 2011. Logistic regression models from a random sample of 3,842 individuals aged ≥ 15 years were used to classify individuals according to the state of their personal autonomy. Predictive models were proposed to identify indicators that helped distinguish dependent individuals from those at risk of dependence. Variables on […]

OBJECTIVE To estimate the effect of age, period and birth cohort on mortality from cancer of the cervix. METHODS Mortality data for cervical cancer in women aged over 30, between1980 and 2009, for the municipalities of Rio de Janeiro and Sao Paulo, Southeastern Brazil,were extracted from the Mortality Information System. The estimated annual percentage change was calculated for the periods 1980-1994 and 1995-2009. Age, period and cohort effects were assessed employing the Poisson regression model, using estimated functions, deviations, curvatures […]

OBJECTIVE: To develop a hospital mortality prediction model based on data from the Hospital Information System of the Brazilian National Health System. METHODS: This was a cross-sectional study using data from 453,515 authorizations for hospital admission relating to 332 hospitals in Rio Grande do Sul, Southern Brazil in the year 2005. From the ratio between observed and expected deaths, the hospitals were ranked in an adjusted manner, and this was compared with the crude ranking of the mortality rate. Logistic […]

Ordinal logistic regression models have been developed for analysis of epidemiological studies. However, the adequacy of such models for adjustment has so far received little attention. In this article, we reviewed the most important ordinal regression models and common approaches used to verify goodness-of-fit, using R or Stata programs. We performed formal and graphical analyses to compare ordinal models using data sets on health conditions from the National Health and Nutrition Examination Survey (NHANES II).

OBJECTIVE: To empirically compare the Cox, log-binomial, Poisson and logistic regressions to obtain estimates of prevalence ratios (PR) in cross-sectional studies. METHODS: Data from a population-based cross-sectional epidemiological study (n = 2072) on elderly people in Sao Paulo (Southeastern Brazil), conducted between May 2003 and April 2005, were used. Diagnoses of dementia, possible cases of common mental disorders and self-rated poor health were chosen as outcomes with low, intermediate and high prevalence, respectively. Confounding variables with two or more categories […]

OBJECTIVE: To evaluate health status of the elderly in Mexico through their self-perception and to describe social, organizational and health-related factors. METHODS: A study was carried out on secondary data from the 2000 National Health Survey in Mexico. Multiple logistic regression models were used. The dependent variable health status was measured through self-perception. The independent variables included were: sociodemographic characteristics, risk behaviors, accidents, disease diagnosis and clinical measures. RESULTS: A total of 7,322 adults aged 60 years and older were […]

OBJECTIVE: To develop and compare two mathematical models, the first one based on logistic regression and the second one on fuzzy sets theory, aiming at defining a laboratory testing-based measure of indication for submitting patients to parathyroid scintigraphy. METHODS: One-hundred and ninety-four patients with serum calcium and parathyroid hormone available were identified from the data registry of parathyroid scintigraphy of a diagnostic laboratory in São Paulo, Southern Brazil, in the period between January 2000 and December 2004. The logistic regression […]

OBJECTIVE: To verify the prevalence and identify the risk factors related to mental health problems among schoolchildren and its possible association with the beliefs and educational attitudes of parents/caretakers. METHODS: Cross-sectional study with a stratified probabilistic sample (n=454) of first to third-graders from public and private schools in Southeastern Brazil. Standardized instruments were administered to parents/caretakers by trained interviewers, including screening questionnaires for mental health problems among children and parents/caretakers; a questionnaire on beliefs and attitudes; and a questionnaire for […]