Table 3: Significant risk factors for atopic dermatitis in 907 twin pairs, 3–9 years of age, discordant for atopic dermatitis.

All twin pairsMZ twin pairsDZ twin pairs
OR (95% CI)P valueOR (95% CI)P valueOR (95% CI)P valueP value1

Birth weight1.02 (0.81–1.28)0.8840.96 (0.12–7.86)0.9720.98 (0.77–1.24)0.880NS
Birth length1.00 (0.08–13.03)1.008.31 (N/A)0.8541.62 (0.11–22.01)0.758NS
Apgar score1.23 (1.06–1.44)0.0081.19 (0.60–2.34)0.6151.21 (1.04–1.42)0.015NS
Female sex1.31 (1.06–1.61)0.0121.31 (1.07–1.61)0.011NS

Only statistically significant predictors for atopic dermatitis are presented in the table (adjusted for birth weight, birth length).
1Test for heterogeneity between odds ratios for MZ and DZ twin pairs.
NS: nonsignificant.