Table 1 Main characteristics of studies included in the systematic review
Study characteristics | Number of studies |
|---|---|
Total | 10 |
Study period | |
 2000–2007 | 7 |
 2008–2014 | 3 |
Region | |
 Africa | 1 |
 Asia | 7 |
 South America | 2 |
Sample size analysed | |
 < 1000 | 2 |
 1001–5000 | 1 |
 5001–10,000 | 3 |
 10,001–100,000 | 4 |
Age category (in years) | |
 0–10 | 6 |
 11–17 | 2 |
 18–79 | 2 |
Urbanicity | |
 Urban | 7 |
 Rural/urban | 1 |
 Unclear/not reported | 2 |
Method for assessing prevalence | |
 ISAAC questionnaire | 8 |
 ECHRS questionnaire | 2 |