Figure 1 The locations for study area(A), home addresses of subjects (B, D), outpatient clinics and monitoring stations (C, D), and the incidence of eczema in five different districts(B).
6640 mothers of newborns without congenital disease participated in the survey, of whom 139 were multiples, and after further exclusion, a total of 6501 singleton births without congenital disease served as the baseline population for the birth cohort, and after 2 years of follow-up, a total of 5819 study subjects completed follow-up, with a 10.5% (682/6501) lost to follow-up rate over 2 years. A total of 1155(19.8%) of the 5819 study subjects had eczema before the age of 2 years, with 996(17.1%) children with eczema at 1 year of age and 229 (3.9%) with eczema at 2 years of age (Figure 2). A higher proportion of children with eczema had a history of parental atopy (22.08% vs 18.83%), maternal working during pregnancy (65.71% vs 60.06%), high monthly household income (89.52% vs 86.60%), maternal primipara (53.77% vs 47.81%), infrequent window opening (51.95% vs 60.50%), and use of air purifiers (23.64% vs 20.44%) compared with non-eczema study subjects(P <0.05) (Table1).