Table 2.

Association between socio-psychological determinants, socio-demographic characteristics, health related characteristics, and sexual behavioral characteristics with vaccination intention by risk group (HP4V men study, Amsterdam 2015).

		MSW (N=437)						MSM (N=1053)
		Univariable linear regression analysis			Multivariable linear regression analysisa			Univariable linear regression analysis			Multivariable linear regression analysisa
		Beta	(95%CI)	P-value	Beta	(95%CI)	P-value	Beta	(95%CI)	P-value	Beta	(95%CI)	P-value
Sociopsychological determinants
Risk perception		0.30	(0.21–0.40)	<0.001				0.20	(0.16–0.25)	<0.001
Attitude towards HPV vaccination		0.90	(0.83–0.97)	<0.001	0.57	(0.49–0.66)	<0.001	0.81	(0.78–0.85)	<0.001	0.66	(0.61–0.71)	<0.001
Negative outcome expectancies of HPV vaccination		0.24	(0.15–0.33)	<0.001				0.15	(0.10–0.19)	<0.001	−0.03	(−0.06 to 0.00)	0.031
Anticipated regret about rejecting HPV vaccination		0.55	(0.44–0.65)	<0.001	0.12	(0.05–0.19)	0.001	0.47	(0.42–0.52)	<0.001	0.09	(0.05–0.13)	<0.001
Beliefs about HPV vaccination		0.22	(0.12–0.32)	<0.001				0.11	(0.05–0.17)	<0.001
Subjective norm towards HPV vaccination		0.55	(0.45–0.66)	<0.001	0.12	(0.05–0.19)	0.002	0.38	(0.32–0.43)	<0.001
Descriptive norm towards HPV vaccination		0.74	(0.62–0.88)	<0.001	0.11	(0.01–0.21)	0.024	0.49	(0.43–0.56)	<0.001	0.10	(0.06–0.15)	<0.001
Self-efficacy expectations towards HPV vaccination		0.61	(0.54–0.68)	<0.001	0.29	(0.23–0.35)	<0.001	0.52	(0.45–0.58)	<0.001	0.19	(0.15–0.24)	<0.001
Socio-demographic characteristics
Age				0.128						0.019
	≤26 years	REF			REF			REF			REF
	27–40 years	0.26	(−0.02 to 0.54)		−0.14	(−0.31 to 0.03)	0.103	0.26	(0.08–0.43)		0.09	(−0.02 to 0.19)	0.111
	≥41 years	0.38	(−0.024 to 1.00)		−0.43	(−0.79 to −0.07)	0.021	0.17	(−0.00 to 0.34)		−0.02	(−0.13 to 0.09)	0.711
Educational level				0.150						0.753
	Lower education	REF						REF
	High education	0.25	(−0.09 to 0.59)					−0.03	(−0.20 to 0.15)
Health related characteristics
HIV status				0.405						<0.001
	HIV-negative	REF						REF
	HIV-positive	0.73	(−0.41 to 1.87)					0.37	(0.20–0.54)
	Unknown or not willing to disclose	−0.05	(−0.35 to 0.24)					−0.21	(−0.42 to −0.02)
History of anogenital warts				<0.001						0.007
	No	REF						REF
	Yes	0.75	(0.41–1.09)					0.18	(0.05–0.32)
Sexual behavior
Number of sexpartners in preceding 6 monthsb		0.00	(−0.17 to 0.18)	0.993				0.08	(0.01–0.15)	<0.001
Lifetime number of sexpartnersb,c		0.11	(0.00–0.23)	0.059	0.07	(−0.00 to 0.14)	0.051	0.09	(0.06–0.13)	<0.001	0.03	(0.01–0.05)	0.018
HPV related variables
Knowledge about HPV		0.17	(0.10–0.23)	<0.001	0.06	(0.02 to 0.10)	0.005	0.06	(0.02–0.09)	0.003
Friends with a history anogenital warts				0.017						0.100
	No	REF						REF
	Yes	0.37	(0.07–0.67)					0.11	(−0.02 to 0.24)
Friends with (a history of) anal/penile cancer				0.921						0.194
	No	REF						REF
	Yes	0.38	(−0.71 to 0.79)					0.13	(−0.07 to 0.33)

Abbreviations: HP4V=human papillomavirus preparedness for vaccination; CI=confidence interval; HIV=human immunodeficiency virus; HPV=human papillomavirus; MSW=men who have sex with only women only; MSM=men who have sex with men.

^aThe multivariable analyses were executed by adding variables in two steps: (step 1) socio-psychological determinants, (step 2) medical history, sexual behavioral characteristics and HPV related variables. R squared (R²) is a measure that indicates how well the data fit a linear regression model. We found in MSW that after step 1 the R² was 0.70 and after step 2 the R² was 0.71. We found in MSM the R² to be 0.68 after step 1 and this did not change after adding the variables significant in step 2.

^bFor analyses purposes lifetime number of sexual partner was log transformed.

^cin MSW: number of female sex partners; in MSM: number of male sex partners.