Characteristics of the five surveys
| 2008 | 2009 | 2010 | 2011 | 2013 | |
| Number of selected villages/clusters | 40 | 40 | 40 | 31 | 41 |
| Number of subjects assessed | 2517 | 2402 | 2582 | 1933 | 2484 |
| Age, years | |||||
| Mean (SD) | 4.2 (2.3) | 4.1 (2.3) | 4.6 (2.4) | 4.4 (2.5) | 4.5 (2.2) |
| Sex | |||||
| Female, n (%) | 1232 (48.9) | 1169 (48.7) | 1266 (49.0) | 977 (50.6) | 1226 (49.4) |
| Male, n (%) | 1285 (51.1) | 1233 (51.3) | 1316 (51.0) | 956 (49.4) | 1258 (50.6) |
SD, Standard deviation.