Table I. Cross-sectional PPVs: proportion of cat/dog-symptomatic children among subjects with IgE reactivity to cat/dog extract (ImmunoCAP) versus cat/dog allergen molecules (microarray; binomial exact 95% CIs; n = 779).

Cat
Age	Cat extract	Fel d 1		Fel d 2	Fel d 4
4 y	30.2% (18.3% to 44.3%)	25.0% (15.3% to 37.0%)		61.5% (31.6% to 86.1%)	30.0% (6.7% to 65.2%)
8 y	41.7% (32.2% to 51.5%)	42.6% (33.1% to 52.5%)		53.8% (37.2% to 69.9%)	60.0% (32.3% to 83.7%)
16 y	45.5% (37.4% to 53.7%)	41.8% (34.0% to 49.9%)		47.3% (33.7% to 61.2%)	52.6% (35.8% to 69.0%)
Dog
Age	Dog extract	Can f 1	Can f 2	Can f 3	Can f 5	Can f 6
4 y	27.5% (14.6% to 43.9%)	40.0% (16.3% to 67.7%)	71.4% (29.0% to 96.3%)	25% (0.6% to 80.6%)	26.7% (7.8% to 55.1%)	33.3% (4.3% to 77.8%)
8 y	20.0% (12.3% to 29.8%)	53.8% (33.4% to 73.4%)	50% (15.7% to 84.3%)	66.7% (29.9% to 92.5%)	25.0% (13.6% to 39.6)	53.8% (25.1% to 80.8%)
16 y	18.5% (13.1% to 25.0%)	44.2% (29.1% to 60.1%)	40.0% (12.2% to 73.8%)	36.4% (10.9% to 69.2%)	23.5% (15.5% to 33.1%)	33.3% (18.0% to 51.8%)

Boldface values indicate significant differences (95% CIs not overlapping) compared with IgE to dog/cat extract (ImmunoCAP), respectively. NPVs varied between 91.0% (Fel d 4 at age 16 years) and 99.3% (dog extract at age 8 years).