Table 3. Estimated Prevalence of Spondyloarthritis by ESSG Criteria in U.S. Adults Ages 20-69 years: NHANES 2009-10.

Case Type	N	N	%	SE	L 95% CI	U 95% CI
Overall AS	5103	28	0.55	(reporting as having a dx of AS)
Overall AxSpA	5103	70	1.4	0.2	1.0	1.9
20-49 Years	3188	49	1.5	0.2	1.1	2.0
50-69 Years	1915	21	1.3	0.4	0.7	2.5
Gender
Males	2472	24	1.1	0.3	0.6	2.0
Females	2631	46	1.7	0.3	1.2	2.5
Race/Ethnicity Groups
Mexican-Americans	1024	15	1.5*	0.5	0.7	3.0
Non-Hispanic Whites	2244	38	1.5	0.3	1.0	2.3
Non-Hispanic Blacks	963	9	0.9	0.3	0.4	1.8