Table 1.
Characteristics of samples in the national Brazilian Surveillance System of Protective and Risk Factors for Chronic Diseases Telephone Survey (VIGITEL), 2006-2012
| Indicators | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 |
|---|---|---|---|---|---|---|---|
| Interviewed | 54,369 | 54,251 | 54,353 | 54,367 | 54,339 | 54,144 | 45,448 |
| Females (%) | 53.9 | 53.9 | 53.9 | 53.9 | 53.9 | 53.9 | 53.9 |
| Mean age (SD) | 40.1 (16.2) | 40.3 (16.2) | 40.5 (16.2) | 40.8 (16.1) | 40.9 (16.3) | 41.1 (16.3) | 41.3 (16.4) |
| 0-4 years of schooling (%) | 21.6 | 20.4 | 19.4 | 18.0 | 16.8 | 17.2 | 16.1 |
| Response rate (%) | 90.9 | 92.3 | 94.2 | 97.0 | 97.7 | 97.8 | 94.1 |