Fig. 2.

Relationship between the titre of specific IgE to mite, exercise-induced bronchospasm (EIB) and asthma. Serum obtained from asthmatic children with EIB (open squares) and without EIB (open triangles) attending the urban affluent, urban poor or suburban/rural schools were assayed for specific IgE to mite (a) and cockroach (b). The limit of detection for IgE antibodies, represented by the dashed line across the graph, is 0.35 IU/mL. Horizontal lines for each condition indicate the geometric mean of the positive results and values in parenthesis represent the number of samples with negative results. Statistical significance was assessed by a Mann–Whitney U-test.