Table 2

Variation in atopic disease by sibling number

SiblingsAsthma prevalenceOR (95% CI) for asthmaCurrent asthma prevalenceOR (95% CI) for current asthmaHay fever prevalenceOR (95% CI) for hay feverEczema prevalenceOR (95% CI) for eczema
None34.6%
(124/358)
1.00 (reference)24.4%
(87/356)
1.00 (reference)22.9%
(82/358)
1.00 (reference)23.3%
(84/361)
1.00 (reference)
128.8% (700/2427)0.76 (0.60, 0.97)17.9% (431/2406)0.67 (0.52, 0.88)22.0% (536/2433)0.95 (0.73, 1.24)22.5% (550/2440)0.96 (0.74, 1.25)
224.9% (479/1925)0.63 (0.49, 0.80)14.8% (283/1918)0.54 (0.41, 0.70)17.2% (330/1923)0.70 (0.53, 0.92)21.2% (409/1920)0.89 (0.68, 1.16)
326.5%
(228/862)
0.68 (0.52, 0.88)17.1%
(147/859)
0.64 (0.47, 0.86)17.7%
(153/865)
0.72 (0.53, 0.98)21.6%
(187/867)
0.91 (0.68, 1.22)
424.3%
(66/272)
0.61 (0.43, 0.86)15.5%
(42/271)
0.57 (0.38, 0.85)15.6%
(43/275)
0.62 (0.41, 0.94)18.6%
(51/274)
0.75 (0.51, 1.11)
⩾525.8%
(34/132)
0.65 (0.42, 1.02)17.4%
(23/132)
0.65 (0.39, 1.09)20.5%
(27/132)
0.87 (0.53, 1.41)19.5%
(26/133)
0.80 (0.49, 1.31)