Table 3.

Multivariable negative binomial regression model for individually nominated contacts

Variable	Coefficient	Standard Error	P value
PDA (ref paper)	-0.11	0.057	0.057
Pre-entry questionnaire (ref paper)	-0.55	0.055	<0.001
Friday (ref Wed)	-0.06	0.062	0.318
Sunday (ref Wed)	-0.44	0.084	<0.001
Survey day 2 (ref 1)	-0.07	0.064	0.246
Survey day 3 (ref 1)	-0.23	0.073	0.001
Household size (trend)	0.13	0.037	<0.001
Presence of child in the household	0.16	0.086	0.064

Standard error accounts for clustering by subject. Negative binomial overdispersion parameter (mean, 95% CIs): α = 0.31 (0.24, 0.39).