Statistical analysis
Data are presented as means and standard deviations or numbers and percentages. Data were analyzed using IBM SPSS Statistics ver. 23.0 (IBM Co., Armonk, NY, USA). Comparisons between the PFAS and non-PFAS groups were calculated using the Pearson chi-square test or independentt -test as appropriate. Unadjusted and multivariable-adjusted logistic regression models examined associations between PFAS and allergic disease in early childhood. Candidate variables for adjustment included sex, delivery mode, gestational age, parental history of allergic diseases, maternal education level, exclusive breastfeeding during the first 6 months of life, and antibiotic treatment during the first 1 year of life were used to calculate the odds ratio and 95% confidence interval. A P-value of <0.05 was considered statistically significant.