Table 2

Meta-analysis of correlates of human papillomavirus (HPV) vaccine acceptability among men (n=16)9 24 30 34–37 40 42 44–56

Theme	Factor	Number of studies	Effect size	Homogeneity index, Q	Between-study variability, I²
HPV vaccine attitudes	Perceived HPV vaccine benefits	335 42 52	0.51 (0.31, 0.66), p<0.001	6.03, p<0.05	83.42
	Anticipatory regret if not vaccinated	29 51	0.27 (0.21, 0.32), p<0.001	0.59, p=0.44	0.00
	Perceived HPV vaccine effectiveness	69 31 37 42 44 51	0.19 (0.12, 0.26), p<0.001	12.01, p<0.05	58.36
	Fear of needles	430 31 36 40	−0.11 (−0.21, −0.00), p<0.05	2.38, p=0.49	0.00
	Fear of side effects	724 30 35–37 40 44	−0.09 (−0.14, −0.04), p<0.01	3.95, p=0.56	0.00
HPV vaccine endorsements	HCP recommended HPV vaccine	59 24 30 31 51	0.42 (0.13, 0.64), p<0.01	50.84, p<0.01	92.13
	Partner thinks should get vaccine	224 44	−0.41 (−0.51, −0.31), p<0.001	1.62, p=0.20	38.32
	Supportive/accepting social environment	430 35 36 44	0.18 (0.08, 0.27), p<0.001	4.82, p=0.19	37.65
HPV risk perceptions	Perceived HPV risk/susceptibility	109 31 35–37 40 42 45 49 51	0.25 (0.15, 0.34), p<0.001	40.99, p<0.01	78.05
HPV risk perceptions	Perceived HPV severity	79 30 35 40 42 49 51	0.09 (0.03, 0.16), p<0.001	11.05, p=0.09	45.73
Behavioural risk indicators	Number of lifetime sexual partners	637 42 44–46 52	0.18 (0.09, 0.28), p<0.01	11.95, p<0.05	58.16
	Have a current/recent sex partner	624 35 36 40 42 46	0.17 (0.04, 0.30), p<0.05	25.72, p<0.01	80.56
	Did not receive hepatitis B vaccine	29 51	−0.16 (−0.02, −0.08), p<0.001	1.02, p=0.31	2.84
	Smokes cigarettes	49 24 44 51	0.12 (0.02, 0.22), p<0.05	7.06, p=0.07	57.50
	History of STI	430 40 44 51	0.10 (0.01, 0.18), p<0.05	2.99, p=0.39	0.00
HPV education	HPV awareness	424 42 46 51	0.17 (0.05, 0.30), p<0.01	8.83, p<0.05	66.02
HPV education	HPV knowledge	109 30 31 34 35 42 45 46 50 51	0.09 (0.01, 0.16), p<0.05	37.84, p<0.01	76.22
Structural barriers	Cost	730 31 35 36 40–42	−0.17 (−0.25, −0.07), p<0.001	31.94, p<0.01	81.22
	Logistical barriers (hassle, time)	69 30 36 42 44 51	−0.16 (−0.32, −0.00), p<0.05	49.20, p<0.01	89.84
	Need for multiple shots	230 31	−0.16 (−0.27, −0.05), p<0.01	0.23, p=0.89	0.00
Socio-demographic characteristics	Employed	39 36 51	0.13 (0.03, 0.22), p<0.05	0.49, p=0.78	0.00
	Non-white ethnicity	89 30 31 35 42 44 45 51	0.09 (0.03, 0.15), p<0.01	6.86, p=0.44	0.00
	Education	99 30 31 35–37 44 49 51	0.08 (−0.00, 0.16), p=0.054	15.95, p<0.05	49.86

HCP, healthcare providers; STI, sexually transmitted infection.