Sample

General outline

The ELSI-Brazil sample was designed to be representative of the Brazilian population aged 50 and older. Data from the 2010 National Census carried out by the Brazilian Institute of Geography and Statistics (IBGE) were used for sampling design. The estimated sample size was 10,000. This sample size, at a level of significance of 95% and an effect sample design of 1.5, allows an estimated prevalence of 1% with a sample error of 0.25%, or a prevalence of 5% with a sample error of 0.55%. For the same level of significance and effect sample design, it is also possible to identify differences of 2.2% for a prevalence of 10% with the power of the test equal to 80%.

Selection of municipalities

The municipalities were allocated to four strata depending on their population size. To decide the size of the municipality and the number of municipalities allocated to each stratum, the Lavallée & Hidiroglou’s (1988) method of stratum construction was performed, using the R stratification package. The four strata were categorized as follows: first stratum (≤ 26,700 inhabitants from 4,420 municipalities); second stratum (26,701 – 135,000 inhabitants from 951 municipalities); third stratum (135,001 – 750,000 inhabitants from 171 municipalities); fourth stratum (> 750,000 inhabitants from 23 municipalities). For the first three strata i.e. municipalities up to 750,000 inhabitants, the sample was selected in three stages. In the fourth stratum, that included the largest municipalities, the sample selection was done in two stages.

Selected municipalities

Figure 1 and Table 1 show the list of selected municipalities by geographic region and state.

Figure 1 – ELSI-Brazil: selected municipalities by state and Federal District.

Table 1 – ELSI-Brazil: List of selected municipalities by geographical region and state.

Geographical region State Municipality
North Amazonas Autazes
Manaus
Pará Ananindeua
Belém
Placas
Portel
Northeast Maranhão Rosário
São José de Ribamar
São Luís
São Raimundo do Doca Bezerra
Piauí Teresina
Ceará Fortaleza
Groaíras
Limoeiro do Norte
Rio Grande do Norte Natal
Paraíba Arara
Pernambuco Água Preta
Camaragibe
Jaqueira
Recife
Alagoas Maceió
Marechal Deodoro
Sergipe Japoatã
Bahia Feira de Santana
Itajuípe
Itapetinga
Salvador
Urandi
Southeast Minas Gerais Belo Horizonte
Capelinha
Coroaci
Divinópolis
Orizânia
Salinas
Espírito Santo Cachoeiro de Itapemirim
Ibatiba
Rio de janeiro Duque de Caxias
Macaé
Nova Iguaçu
Rio de Janeiro
São Gonçalo
São Pedro da Aldeia
São Paulo Araçatuba
Campinas
Guapiaçu
Guarujá
Guarulhos
Igarapava
Mauá
Salto
São Bernardo do Campo
São Caetano do Sul
São Paulo
Tabatinga
South Paraná Curitiba
Pato Branco
Santa Maria do Oeste
São José dos Pinhais
Santa Catarina Taió
Rio Grande do Sul Canoas
Charqueadas
Porto Alegre
São Paulo das Missões
Midwest Mato Grosso do Sul Campo Grande
Mato Grosso Chapada dos Guimarães
Goiás Anápolis
Goianésia
Goiânia
Vicentinópolis
Distrito Federal Brasília