Table 2. Odds Ratios (OR) and 95% Confidence Intervals (CI) for hay fever prevalence among NHIS respondents (2002–2013).

		OR	9%% CI	OR1	95% CI
Changes in Plant Pnenology
	> 3wk Early	1.13	1.05–1.22	1.14	1.03–1.27
	1–3 wk Early	0.96	0.92–1.00	0.95	0.9–1.00
	1 wk early to 1 wk late	1.00	REF	1.00	REF
	1–3 wk Late	1.05	0.99–1.11	1.05	0.99–1.12
	>3 wk Late	1.14	1.06–1.21	1.18	1.05–1.32
Age Groups
	18–34	1.00	REF	1.00	REF
	35–49	1.91	1.82–2	1.86	1.76–1.96
	50–64	1.90	1.81–1.99	1.85	1.75–1.95
	> = 65	1.32	1.25–1.39	1.25	1.17–1.32
Race/Ethnicity
	Non-Hispanic White	1.42	1.34–1.5	1.39	1.29–1.5
	Non-H Black	1.05	0.98–1.13	1.04	0.95–1.14
	Hispanic	1.00	REF	1.00	REF
	Other	1.14	1.04–1.26	1.11	0.99–1.25
Sex
	Male	1.00	REF	1.00	REF
	Female	1.30	1.26–1.34	1.29	1.25–1.34
Education
	<High School	1.00	REF	1.00	REF
	High School	1.37	1.32–1.42	1.38	1.32–1.43
	College	1.53	1.46–1.6	1.54	1.46–1.62
	> College	1.71	1.62–1.8	1.72	1.62–1.83

¹Springtime Interview only