Table 4.

Likelihood of clicking through to study website across gender and age subgroups and social media advertisement features.

			Mean cost per unique click (USD $)	Odds ratio (95% CI) for unique clicks per reach	Odds ratio for unique link clicks per reach
					Male		Female
					Age 18–24	Age 25–34	Age 18–24	Age 25–34
Population subgroup	Gendera	Male	0.44	1.01 (0.96–1.06)
		Female	0.46	1.00
	Age	18–24	0.41	1.11 (1.06–1.17)
		25–34	0.48	1.00
Advertisement features	Language	English	0.42	1.00	1.00	1.00	1.00	1.00
		Spanish or bilingual	0.47	0.88 (0.82, 0.93)	0.68 (0.59, 0.78)	1.54 (1.34, 1.76)	0.70 (0.63, 0.78)	0.90 (0.82, 0.99)
	Diabetes-related imagery	No	0.45	1.00	1.00	1.00	1.00	1.00
		Yes	0.44	0.96 (0.91–1.00)	1.22 (1.09, 1.37)	0.74 (0.66, 0.84)	1.11 (1.01, 1.23)	0.88 (0.80, 0.95)
	Compensation	No	0.43	1.00	1.00	1.00	1.00	1.00
		Yes	0.47	1.04 (0.99, 1.09)	1.50 (1.34, 1.68)	0.52 (0.46, 0.59)	1.78 (1.62, 1.96)	0.89 (0.82, 0.96)
	Urgency/time running out	No	0.47	1.00	1.00	1.00	1.00	1.00
		Yes	0.39	0.54 (0.50–0.57)	0.46 (0.40, 0.53)	0.99	0.36 (0.32, 0.40)	0.62 (0.55, 0.71)
	Altruism	No	0.41	1.00	1.00	1.00	1.00	1.00
		Yes	0.87	1.60 (1.49–1.73)	1.32 (1.10, 1.58)	2.02 (1.66, 2.47)	1.43 (1.24, 1.66)	1.70 (1.51, 1.90)
	Study team’s empathy	No	0.45	1.00	1.00	1.00	1.00	1.00
		Yes	0.43	1.80 (1.69–1.92)	1.98 (1.72, 2.28)	2.44 (2.10, 2.85)	2.08 (1.83, 2.38)	1.43 (1.30, 1.57)
	Call to action	No	0.35	1.00	1.00	1.00	1.00	1.00
		Yes	0.53	0.53 (0.50–0.56)	0.85 (0.76, 0.97)	0.25 (0.22, 0.28)	1.00	0.40 (0.36, 0.43)
	Difficult aspects of managing diabetes	No	0.56	1.00	1.00	1.00	1.00	1.00
		Yes	0.39	0.88 (0.84–0.93)	1.12	0.60 (0.53, 0.68)	1.06	0.85 (0.78, 0.92)

^aUnknown were excluded from the analyses.

Bold text indicates statistical significance at p<0.05