TABLE 2—

Odds Ratios of Helmet Use for Bikeshare Users Compared with Riders of Private Bicycles: Washington, DC, September–October 2011

	Wearing Helmet, No./Total No. (%)	Unadjusted OR (95% CI)	Adjusted OR (95% CI)
Commuters
Private bicycle	898/1268 (70.8)	1.000 (Ref)	1.000 (Ref)
Bikeshare	47/142 (33.1)	0.204 (0.117, 0.356)	0.200 (0.110, 0.362)
Casual riders
Private bicycle	531/776 (68.4)	1.000 (Ref)	1.000 (Ref)
Bikeshare	17/108 (15.7)	0.086 (0.057, 0.131)	0.090 (0.061, 0.132)

Note. CI = confidence interval; OR = odds ratio. Adjusted odds ratios are controlled for gender and age.