Table 2

Percentage of asthma cases attributable to atopy based on number of positive skin prick tests and specific skin prick tests

Skin prick tests2-150 % Non asthmatics atopic (n =399)% Asthmatics atopic (n =315)Relative risk% of cases attributable to atopy
No. of positive tests
 1+35.157.12.534
 2+16.540.63.529
 3+7.327.34.822
 4+2.014.38.113
 5+1.09.810.89
 6+0.57.014.97
 7+0.32.911.73
Specific skin prick tests
 Any positive test35.157.12.534
 Rye grass23.444.42.627
 House dust mite19.443.73.230
 Cat5.523.25.219
Alternaria 4.58.62.04
 Dog 2.29.94.98
 Horse1.810.26.39
Cladosporium 1.35.74.74
 Kapok1.54.12.83
Aspergillus fumigatus 0.54.89.74
 Wool0.84.46.04
Penicillium 2.02.51.31
  • 2-150 Defined as the development of weals at least 2 mm greater than negative control.

  • Adapted from Sears et al.22