TABLE 1—

Characteristics of Human Papillomavirus Vaccine Posts on Pinterest by Time Period

Variable/Subvariable	Before Actions to Moderate Contenta (n = 500), % (no.)	After Actions to Moderate Contentb (n = 203), % (no.)	Pc
Pinner source
Individual	79.2 (396)	25.8 (129)	< .001
Individual small business	4.0 (20)	2.6 (13)	.22
Commercial	2.8 (14)	4.0 (20)	.30
Government	0 (0)	7.6 (38)	< .001
Official medical	3.2 (16)	46.2 (231)	< .001
Other health-focused	5.6 (28)	5.2 (26)	.78
Medical professional	1.6 (8)	0.6 (3)	.13
Antivax organization	1.2 (6)	0 (0)	.014
Other	1.8 (9)	6.0 (30)	< .001
Visual type
Primarily image	64.4 (322)	36.0 (180)	< .001
Primarily text	9.4 (47)	15.6 (78)	.003
Mix of image and text	16.4 (82)	29.2 (146)	< .001
Infographic	3.6 (18)	10.0 (50)	< .001
Drawing	0 (0)	1.6 (8)	.005
Video	6.0 (30)	5.4 (27)	.68
Other	0.2 (1)	2.2 (11)	.004
Fear visual	32.2 (161)	14.2 (71)	< .001
Health Belief Model
Perceived benefits vaccine	13.0 (65)	40.4 (82)	< .001
Perceived barriers vaccine	65.6 (328)	11.3 (23)	< .001
Perceived severity HPV	3.6 (18)	23.2 (47)	< .001
Perceived susceptibility HPV	5.0 (25)	21.7 (45)	< .001
Cue to action—get vaccine	8.2 (41)	14.8 (30)	< .001
Self-efficacy—get vaccine	2.6 (13)	5.9 (12)	< .001
Barriers
Conspiracy	13.8 (69)	1.2 (6)	< .001
Vaccine adverse reactions	55.0 (275)	1.6 (8)	< .001

Note. HPV = human papillomavirus. Pinner source and visual type categories were mutually exclusive, Health Belief Model constructs were not.

^aCollected October 2, 2018.

^bCollected December 2, 2019. A portion of the total sample of n = 500 was not relevant; only the relevant search results (n = 203) are included here.

^cP values determined by χ² test, unless cell size was < 5, in which case the Fisher exact test was used.