Table 1. Sociodemographic characteristics among adults aged ≥18 years–United States, National Internet Flu Survey 2015.

Characteristic	Unweighted Sample Size, No.	Weighted Percentage % (95% CI)
Total	3,301	100.0
Age
18–49 years	1,508	54.7 (53.8, 55.6)
50–64 years	1,033	26.0 (25.3, 26.7)
≥65 years	760	19.3 (18.6, 19.9)
Gender
Male	1,622	48.3 (46.3, 50.4)
Female	1,679	51.7 (49.6, 53.7)
Race/ethnicity
Non-Hispanic white only	1,922	65.5 (64.3, 66.7)
Non-Hispanic black only	494	11.8 (11.0, 12.6)
Hispanic	460	14.1 (13.0, 15.3)
Non-Hispanic, other or multiple races	425	8.6 (7.7, 9.5)
Marital status
Married/living with partner	1,950	57.9 (55.9, 59.9)
Widowed/divorced/separated	616	17.7 (16.2, 19.2)
Never married	735	24.5 (22.7, 26.3)
Education level
Less than high school	269	12.0 (10.5, 13.6)
High school	892	29.4 (27.6, 31.3)
Some college	956	28.5 (26.8, 30.4)
Bachelor's degree or higher	1,184	30.1 (28.4, 31.8)
Employment
Employed	1,862	58.5 (56.6, 60.3)
Unemployed	188	6.3 (5.3, 7.5)
Not in work force	1,251	35.2 (33.5, 36.9)
Annual household income
<$35,000	945	27.2 (25.5, 29.1)
$35,000-$49,999	374	11.6 (10.3, 13.0)
$50,000-$74,999	628	17.9 (16.4, 19.5)
≥$75,000	1,354	43.3 (41.3, 45.3)
Region of residence
Northeast	590	18.1 (16.6, 19.7)
Midwest	693	21.4 (19.8, 23.1)
South	1,185	37.1 (35.1, 39.0)
West	833	23.4 (21.8, 25.1)
MSA status
Metro	2,885	85.0 (83.5, 86.4)
Non-metro	416	15.0 (13.6, 16.5)
Household size
One	723	21.2 (19.6, 22.9)
Two	1,272	36.1 (34.3, 37.9)
Three or more	1,306	42.7 (40.8, 44.7)
Received influenza vaccination
Yes	1,354	39.9 (38.0, 41.8)
No	1,894	60.1 (58.2, 62.0)