Population	Number of people	Asthma: OR [95% CI] based on proximity to road			References
Population	Number of people	No-exposed	Exposed	p	References
South Africa Children	423	1	1.12 [1.01 - 1.24]	0.04	Naidoo et al., 2013 [32] .
South Africa Children	3764	1	1.60 [1.24 - 2.02]	0.000	Shirinde et al., 2015 [33] .
Ethiopia Adults Children	3592	1	1.17 [1.01 - 1.36]	0.03	Venn et al., 2005 [34] .
ISAAC Phase 3 centers in Africa (Morroco and Nigeria) Children	2656	1	1.24 [1.14 - 1.35]	-	Brunekreef et al., 2009 [35] .