Prevalence of atopic sensitization and asthma in children aged 13 years with a history of thumb-sucking or nail-biting. Prevalence of atopic sensitization and asthma in children aged 13 years with a history of thumb-sucking or nail-biting. Error bars show the 95% confidence intervals. The statistical significance of differences between oral habit categories from χ2 tests are P = .05 for atopy, P = .76 for asthma, and P = .27 for hay fever. Stephanie J. Lynch et al. Pediatrics doi:10.1542/peds.2016-0443 ©2016 by American Academy of Pediatrics