Table 2
Age and sex of samples
Sample (% males)
Mean age (years)
SD (range)
⩽6 years
7–8 years
⩾9 years
⩽13 years
14 years
⩾15 years
Children (51.4)
6.7
0.7 (5–11)
40.5%
59.2%
0.3%
Adolescents (51.6)
13.3
0.5 (12–17)
76.3%
20.7%
2.7%