Table 3

Percentage of asthma cases attributable to atopy (defined as a total serum IgE level of 100+ IU/ml) in population based studies

Reference		Age		Non-asthmatics				Asthmatics		Relative risk	% of cases attributable to atopy	Definition of asthma
Reference		Age		No.	Atopy (%)			No.	Atopy (%)	Relative risk	% of cases attributable to atopy	Definition of asthma
Burrows et al ⁴	6–34	994	30		89	73	6.3	61	“Asthma” + symptoms
	35–54	498	18		47	57	6.0	48	“Asthma” + symptoms
	55+	928	13		101	34	3.5	24	“Asthma” + symptoms
Remes and Korppi28	7–12	204	45		43	38	0.7	–16	Clinical examination
Sears et al 35	11	500	46		62	89	9.5	80	Diagnosed current asthma
Burrows et al 36 ^3-150	15+	2255	12		160	38	4.5	30	Current diagnosed asthma
Sunyer et al 20	20–44	1761	25		155	50	3.0	33	Asthma attack ever
Bodner et al 33	39–45	217	13		102	23	2.0	11	Adult onset wheeze