Biomedical subjects

Eduardo Faerstein

Publications and source records attributed to Eduardo Faerstein.

4 recordsLinked to original sources

PubMed2003

How reproducible is self-reported information on exposure to smoking, drinking, and dietary patterns? Evidence among Brazilian adults in the Pró-Saúde Study.

CONTEXT: Epidemiological studies of the validity and reliability of self-reported information on important risk factors for non-communicable chronic diseases are scarce in Brazil. OBJECTIVE: We evaluated the test-retest reliability of information--overall and stratified by gender, age and education--on active and passive smoking, alcohol intake and aspects of dietary habits. TYPE OF STUDY: Test-retest reliability. SETTING: Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil. PARTICIPANTS: 192 University employees. PROCEDURES: Self-administered questionnaires were completed on two occasions, two weeks apart. MAIN MEASUREMENTS: Kappa Statistics; Intraclass Correlation Coefficient. RESULTS: Information on smoking status and pack-years smoked had almost perfect levels of agreement, respectively, kappa = 0.97 (95% CI, 0.92-1.00), and intraclass correlation coefficient = 0.93 (CI 95%, 0.89-0.96). Characteristics of alcohol intake yielded substantial levels of agreement (kappa ranging from 0.62 to 0.69). The reproducibility of the information on dietary habits varied from 0.67 to 0.79 (kappa). No clear-cut patterns could be identified comparing information by age or gender. There was a slight tendency towards greater reliability among people with higher levels of education. CONCLUSION: The reproducibility of information on smoking, drinking, and dietary patterns ranged from substantial to excellent, as investigated in the Pró-Saúde Study, a longitudinal investigation recently launched in Rio de Janeiro.

Adolescent↗

PubMed2003

[Test-retest reliability of measures of social network in the "Pró -Saúde" Study].

OBJECTIVE: To evaluate test-retest reliability of social network-related information of the" Pr -Sa de" study. METHODS: A test-retest reliability study was conducted using a multidimensional questionnaire applied to a cohort of university employees. The same questionnaire was filled out twice by 192 non-permanent employees with two weeks apart. Agreement was estimated using kappa statistics (categorical variables), weighted kappa statistics, log-linear models (ordinal variables), and intraclass correlation coefficient (discrete variables). RESULTS: Estimates of reliability were higher than 0.70 for most variables. Stratified analyses revealed no consistently varying patterns of reliability according to gender, age or schooling strata. Log-linear modelling showed that, for the study ordinal variables, the model of best fit was "diagonal agreement plus linear by linear association". CONCLUSIONS: The high level of reliability estimated in this study suggests that the process of measurement of social network-related aspects was adequate. Validation studies, which are currently being conducted, will complete the quality assessment of this information.

Adult↗

PubMed2003

[Social support: scale test-retest reliability in the Pro-Health Study].

This article describes the test-retest reliability of a scale comprising five dimensions of social support: material, emotional, informational, affective, and positive social interaction. In the study, a sample of 192 employees at a university in Rio de Janeiro filled out the same questionnaire on two occasions, 15 days apart. Measures of stability used were the intraclass correlation coefficient (ICC), weighted kappa statistic, and log-linear models. Internal consistency was evaluated using the Cronbach's alpha coefficient. Social support dimensions showed internal consistency ranging from 0.75 to 0.91 at test, and 0.86 to 0.93 at retest. The ICC ranged from 0.78 to 0.87 in the five dimensions of the scale, with no substantial differences by gender, age, or level of schooling. For most questions, the "agreement plus linear by linear association" and "quasi-association" log-linear models gave the best fit. According to these results, the reliability of the instrument was considered adequate, enabling it to be used in ongoing assessment of associations between social support and health-related outcomes in a cohort study (the Pro-Health Study) recently begun in Rio de Janeiro.

Adult↗

PubMedDate not supplied

[Survival analysis techniques].

Statistical methods known as survival analyses are useful for analyzing time-related events, in which time from a benchmark event to an endpoint is the focus of interest. Survival analysis describes not only patient survival statistics (as suggested by the name), but also other dichotomous outcomes such as time of remission, time of breastfeeding, etc. This paper discusses survival analysis techniques, commenting and comparing their utilization, especially in the field of oncology. It also presents and discusses types of epidemiological studies and data sources to which this type of analysis is applied. The authors take into account the difference between hospital-based or clinical series and population-based approaches. Interpretation of results is also discussed.

Data Interpretation, Statistical↗