Table 3.

Personal protection and vector control among malaria case-patients and matched controls, Naxalbari, Darjeeling, West Bengal, India, 2005

Characteristics	Cases (n = 534)		Controls (n = 534)		Matched odds ratio
	#	%	#	%	Estimate	95% confidence interval
Sleeping outdoors every night	190	36	150	32	3.8a	2.2 - 6.5
Using coils or repellent creams daily	120	23	152	29	0.1b	0.06 - 0.3
Using bet nets every nightc	98	18	133	25	0.3d	0.1 - 0.5
Underwent indoor residual spray (DDT)	213	40	220	41	0.9	0.7 - 1.2

^a Fraction attributable to sleeping outdoors: 26%

^b Fraction attributable to the failure to use repellents: 69%

^c No insecticide impregnation in place at the time of the outbreak

^d Fraction attributable to the failure to sleep under a bed net: 57%