Table 4.

Bladder Cancer Odds Ratio and 95% Confidence Interval for Different Etiologic Factors, Adjusted for Smoking Status, Area, Sex, Age, and a Component for Random Interviewer Effects, Among All Study Subjects and by Overall Quality of Interview, Spain, June 1998–June 2001

	Occupation
	All Subjects (N  =  2,315)		Unsatisfactory/Questionable Interviews (n  = 186)		Reliable/High Quality Interviews (n  = 2,129)
	Odds Ratio	95% Confidence Interval	Odds Ratio	95% Confidence Interval	Odds Ratio	95% Confidence Interval
Non-high risk	1.00		1.00		1.00
High risk	1.51	1.21, 1.89	1.47	0.66, 3.29	1.52	1.21, 1.92
	Average Residential Trihalomethane Levels
	All Subjects (N  = 1,536)		Unsatisfactory/Questionable Interviews (n  = 91)		Reliable/High Quality Interviews (n  = 1,445)
	Odds Ratio	95% Confidence Interval	Odds Ratio	95% Confidence Interval	Odds Ratio	95% Confidence Interval
≤26 μg/L	1.00		1.00		1.00
>26 μg/L	1.76	1.25, 2.46	1.34	0.29, 6.28	1.82	1.28, 2.58
	Nonsteroidal Antiinflammatory Drugs
	All Subjects (N  = 1,749)		Unsatisfactory/Questionable Interviews (n  = 115)		Reliable/High Quality Interviews (n  = 1.634)
	Odds Ratio	95% Confidence Interval	Odds Ratio	95% Confidence Interval	Odds Ratio	95% Confidence Interval
Never	1.00		1.00		1.00
Long-term users	0.49	0.23, 1.03	1.07	0.06, 18.98	0.45	0.21, 0.98