Editorial

EDITORIAL

Chester Luiz Galvão Cesar; Rita Barradas Barata

Population surveys are key tools in the production of strategic information for the formulation of health policies, in addition to being traditional tools in the production of knowledge on population health.

Following an initiative of ABRASCO's Epidemiology Committee to prepare seminars dedicated to the in-depth discussion of conceptual, methodological and operational issues of each one of the key investigation designs normally used in epidemiological research, a partnership was made with the Department of Social Medicine of the Santa Casa de SP Medical School and the São Paulo University School of Public Health for a seminar dedicated to population surveys.

Household surveys are an ancient practice and, since the 19th century, they have been widely used both by sociology and epidemiology. In Brazil, at least since the initial decades of the 20th century, there have been records of household surveys as sources of sociodemographic and epidemiological information.

During the 1970's, Carvalheiro introduced health surveys in Ribeirão Preto, in the same patterns conducted by the American National Health Institutes.

With time, the methods for performing and analyzing data from surveys have improved, enabling greater accuracy and exactness in the estimates obtained, and mainly, guaranteeing external validity of findings, and providing safer generalizations of sample data for the population.

The Seminar program was organized to allow for the presentation and the debate of large domestic population surveys, such as The Global Health Research, the National Household Sample Survey – Health Supplement, National Demographic and Health Survey, National Vaccination Coverage Survey.

There are many methodological issues related to population-based health surveys. One of them relates to sample plans which are necessarily complex in order to have large enough and representative samples to confer statistical power and accuracy to estimates. In this aspect there has been progress, both in sample theory and data analysis techniques, points that are dealt with in this seminar and approached in the articles presented in this number.

Another important point with implications to results refers to biases introduced by operational procedures, such as the use of indirect informants, phone interviews, refusals, and loss of information, among others. Some of these issues are also dealt with in the articles presented in this issue.

The frequency and domestic and international comparability of surveys such as the Survey on Demographics and Health (DHS) were also debated in the seminar and are portrayed in the texts published in this supplement.

The utilization of home surveys for the assessment of public policies has also been analyzed, based on the specific case of vaccine coverage surveys as tools for the assessment of the National Immunization Program and the analyses of PNAD's (National Home Sampling Survey) health supplement. Some of the papers presented here address those issues.

The utilization of home surveys as a source of information for the study of health inequalities has also received the attention of the participants of the seminar, with the reflections of Brazilian researchers and the contribution of the experience of the Carme Borrell group from Catalonia.

The possibility of integrating qualitative and quantitative approaches in the performance of home surveys has been included into the reflections of professor Irene Luppi from the Juan Lazarte de Rosário Health Institute in Argentina.

We also considered the utilization of home surveys as the guiding line of a masters program in epidemiology and the advantages and limitations of this experience. Some of the texts published in this supplement deal with these aspects.

In addition to the academic objectives already pointed out, the program also included a debate on the appropriateness of the implementation by the Ministry of Health of National Health Surveys following those conducted by the British NHS and by the American NIH, as decision-making tools based on epidemiological information, at the level of the design of health policies.

The papers that comprise this supplement portray the content of the presentations and debates in the seminar. We asked the authors of each of the presentations to prepare texts for this supplement. At the end, we have included an article with a summary of the debates that took place in the plenary sessions after each one of the presentation sessions. Based on the notes of the reporters, we have written a single text providing readers with an overview of the debates and relevant issues.

Finally, we are also publishing the summaries of the population surveys presented as posters, which were previously selected by the organizing committee.

In this manner, we believe we are offering practitioners of Epidemiology—teachers, researches and professionals—important elements for the improvement of population-based surveys. Moreover, we hope that this supplement may be widely used by the students of our post-graduation programs.

Publication Dates

• Publication in this collection
  20 May 2008
• Date of issue
  May 2008