Table 1.

Demographics of the original study cohort stratified by those children who had FeNO measured at age 7 and whether they were included in the final analyses

	Children with FeNO not tested age 7 (n=831)	Children with FeNO tested age 7 (n=144)	Children included in analysesa (n=89)b
Age at enrollment (mean [CI])	4.05 [4.01–4.09]	3.93 [3.84–4.01]*	3.91 [3.79–4.03]
Age at eNO measurement(mean [CI])	-	6.87 [6.71–7.03]	6.87 [6.65–7.07]
Boys (%)	50	50	46
Race/Ethnicity
Dominican (%)	23	29	34
Mexican (%)	25	42**	43
Puerto Rican (%)	17	6.9**	6.7
Other Hispanic/Mixed (%)	16	17	14
African-American (%)	20	4.2**	3.4
Other (%)	1.2	0.7	0
Current wheeze age 4 visit (%)	27	28	27
Current wheeze at eNO age (%)	-	27	21
ED visit wheeze initial visit (%)	16	17	15
ED visit at eNO visit (%)	-	15	14
Seroatopy age 4c(%)	32	40	33
Seroatopy age 7d(%)	-	47	47
Any smoker in home age 4 (%)	24	29	29
Any smoker in home at age 7 (%)	-	11	15

^*P<0.05,

^**P<0.01 for difference from children without FeNO collected.

^aChildren were included in the analyses if they had valid FeNO and lung function tests, serum IgE results and questionnaire information on wheeze at age 7 years.

^bThere were no statistically significant (P<0.05) differences in any of the demographics represented between the children with FeNO tested, but not included in the analyses (n=55) and the children included in the analyses (n=89).

^cSeroatopy was defined as having measurable specific IgE (≥0.35 IU/ml) to at least one of any of the four allergens tested (Dermatophagoides farinae, German cockroach, mouse or cat). By study design, only half of the original cohort subjects at age 4 were eligible for serum IgE measurement. The sample size for the prevalence figures in the table were 354, 52 and 86 for the children without FeNO, with FeNO and included in analyses, respectively.

^dThere were 135 children who had both FeNO and IgE measured at age 7.