TABLE 3—

Estimated Odds Ratios and 95% Confidence Intervals of Survey Factors Compared With Reference Categories: British Columbia, Canada, 2012–2013

Survey Factors	OR (95% CI)
Sampling frame
InfoCanada	1.14 (0.98, 1.34)
Canada Post (Ref)	1.00
Lottery incentive
Instant	1.35 (1.16, 1.58)
End-of-study (Ref)	1.00
Survey length
Short	1.35 (1.13, 1.62)
Long (Ref)	1.00
Prepaid incentive
Coin	1.44 (1.23, 1.67)
No coin (Ref)	1.00
Administration mode
Paper	2.04 (1.61, 2.59)
Online (Ref)	1.00

Note. CI = confidence interval; OR = odds ratio.