Study characteristics | Studies# n |
Total | 183 |
Year of publication | |
Before 2000 | 30 |
2000–2005 | 48 |
2006–2010 | 67 |
After 2010 | 38 |
Level of analysis | |
Individual | 155 |
Area level | 14 |
Multilevel | 14 |
Region | |
Africa | 83 |
Asia | 111 |
Europe | 199 |
South America | 61 |
North America | 46 |
Oceania | 25 |
Sample size | |
<200 | 6 |
200–1000 | 31 |
1001–5000 | 60 |
5001–10 000 | 26 |
10 000–100 000 | 30 |
>100 000 | 6 |
Age category | |
Children (<18 years old) | 119 |
Adults | 39 |
Mixed | 25 |
Health outcomes | |
Asthma | 129 |
Wheezing | 52 |
Allergies or allergic reactions | 31 |
Allergic rhinitis (i.e. hay fever) | 22 |
Atopic dermatitis (i.e. eczema) | 27 |
SEP measures¶ | |
Parental or own education level | 79 |
Individual or household income | 76 |
Occupational level or employment status | 43 |
Area-level deprivation or poverty | 22 |
Housing characteristics | 19 |
Country-level SES | 10 |
For a complete overview, see the online supplementary material. SEP: socioeconomic position; SES: socioeconomic status. #: total may exceed 183 as some studies covered multiple regions and used multiple health outcomes and SEP measures; ¶: only most common SEP measures included in table.