. 2012 Feb 1;14(1):e20. doi: 10.2196/jmir.1978

Table 1.

Prevalence ratios of clicking on the Facebook advertisement and submitting an expression of interest

Characteristic		Clicking on an advertisement			Expression of interest
Characteristic		Adjusted PR^a	95% CI^b	P value	PR^c	95% CI	P value
Age group (years)
	16–17	1.00			1.00
	18–21	1.05	0.99–1.11	.10	2.42	1.85–3.19	<.001
	22–25	1.14	1.07–1.21	<.001	3.34	2.56–4.36	<.001
Geographic region
	Major city	1.00
	Regional/rural	0.96	0.90–1.04	.36

^a Prevalence ratios (PRs) of clicking on a Facebook recruitment advertisement, mutually adjusted for geographic region and age group.

^b Confidence interval.

^c PRs of submitting an expression of interest, after clicking on an advertisement. Geographic region is omitted from this analysis because 40.5% (223/551) of respondents did not provide this information.