Non-Adherence To Childhood HPV Vaccination Is Associated With Non-Participation In Cervical Cancer Screening – A Nationwide Danish Register-Based Cohort Study

Figures & data

Figure 1 Inclusion and exclusion flow-chart for the study population, including screening participation according to HPV vaccination status.

Table 1 Socio-Economic Characteristics Of The Study Population And Their Parents, Stratified By Combined Attendance In The Two Preventive Programs Against Cervical Cancer

		Vaccinated Screened			Vaccinated Un-Screened			Un-Vaccinated Screened			Un-Vaccinated Un-Screened
N ; % row (95% CI)		13,893; 55.9 (55.3-56.6)			8,741; 35.2 (34.6-35.8)			856; 3.4 (3.2-3.6)			1,338; 5.4 (5.1-5.6)
Socoeconomic Variables (n, % col)	n	% row	95% CI	n	% row	95% CI	n	% row	95% CI	n	% row	95% CI
Parental civil status ^a
Married/cohabiting (18,762, 75.6%)	10,891	58.1%	(57.3-58.8)	6,479	34.5%	(33.9-35.2)	563	3.0%	(2.8-3.3)	829	4.4%	(4.1-4.7)
Single (6,050, 24.4%)	3,002	49.6%	(48.4-50.9)	2,262	37.4%	(36.2-38.6)	293	4.8%	(4.3-5.4)	493	8.2%	(7.5-8.9)
Missing (16, 0.1%)	0	-	-	0	-	-	0	-	-	16	100.0%	(79.4-100.0)
Individual area of residence
Densely populated (5,832, 23.5%)	2,914	50.0%	(48.7-51.3)	2,282	39.1%	(37.9-40.4)	228	3.9%	(3.4-4.4)	408	7.0%	(6.4-7.7)
Populated at intermediate (9,468, 38.1%)	5,329	56.3%	(55.3-57.3)	3,360	35.5%	(34.5-36.5)	311	3.3%	(2.9-3.7)	468	4.9%	(4.5-5.4)
Thinly populated (9,512, 38.3%)	5,650	59.4%	(58.4-60.4)	3,099	32.6%	(31.6-33.5)	317	3.3%	(3.0-3.7)	446	4.7%	(4.3-5.1)
Missing (16, 0.1%)	0	-	-	0	-	-	0	-		16	100.0%	(79.4-100.0)
Individual country of origin
Denmark (n= 22,271, 89.7%)	13,282	59.6%	(59.0-60.3)	7,240	32.5%	(31.1-33.1)	760	3.4%	(3.2-3.7)	989	4.4%	(4.2-4.7)
Western country (n=225, 0.9%)	95	42.2%	(35.7-49.0)	84	37.3%	(31.0-44.0)	20	8.9%	(5.5-13.4)	26	11.6%	(7.7-16.5)
Non-western country (2,316, 9.3%)	516	22.3%	(20.6-24.0)	1,417	61.2%	(59.2-63.2)	76	3.3%	(2.6-4.1)	307	13.3%	(11.9-14.7)
Missing (16, 0.1%)	0	-	-	0	-	-	0	-	-	16	100.0%	(79.4-100.0)
Parents’ highest education
Higher (8,152, 32.8%)	5,006	61.4%	(60.3-62.5)	2,558	31.4%	(30.4-32.4)	276	3.4%	(3.0-3.8)	312	3.8%	(3.4-4.3)
Middle (12,805, 51.6%)	7,290	59.9%	(56.1-57.8)	4,530	35.4%	(34.5-36-2)	374	2.9%	(2.6-3.2)	612	4.8%	(4.4-5.2)
Low (3,644, 14.7%)	1,541	42.3%	(40.7-43.9)	1,549	42.5%	(40.9-44.1)	195	5.4%	(4.6-6.1)	359	9.9%	(8.9-10.9)
Missing (226, 0.9%)	56	24.8%	(19.3-30.9)	104	46.1%	(39.4-52.8)	11	4.9%	(2.5-8.5)	55	24.3%	(18.9-30.5)
Family income
High (6,102, 24.6%)	4,019	65.9%	(64.7-67.1)	1,734	28.4%	(27.3-29.6)	191	3.1%	(2.7-3.6)	158	2.6%	(2.2-3.0)
Middle (9,845, 39.7%)	5,895	59.9%	(58.9-60.8)	3,320	33.7%	(32.8-34.7)	263	2.7%	(2.4-3.0)	367	3.7%	(3.4-4-1)
Low (8,866, 35.7%)	3,979	44.9%	(43.8-45.9)	3,687	41.6%	(40.6-42.6)	402	4.5%	(4.1-5.0)	798	9.0%	(8.4-9.6)
Missing (15, 0.1%)	0	-	-	0	-	-	0	-	-	15	100.0%	(79.4-100.0)
Parents’ highest occupation
Working (22,789, 91.8%)	13,228	58.1%	(57.4-58.7)	7,750	34.0%	(33.4-34.6)	754	3.3%	(2.1-3.5)	1,057	4.6%	(4.4-4.9)
Temporarely not working (1,264, 5.1%)	379	30.0%	(27.5-32.6)	637	50.4%	(47.6-53.2)	59	4.7%	(3.6-6.0)	189	15.0%	(13.0-17.0)
Permenatly not working (590, 2.4%)	208	35.3%	(31.4-39.3)	279	47.3%	(43.2-51.4)	35	5.9%	(4.2-8.2)	68	11.5%	(9.1-14.4)
Missing (185, 0.8%)	78	42.2%	(35.0-49.6)	75	40.5%	(33.4-48.0)	8	4.3%	(1.9-8.0)	24	13.0%	(8.5-18.7)

Notes: ^aThe parent(s) with whom the child lives. The purpose of the bold values is to emphasis the % values and their 95% CI.

Table 2 Unadjusted And Adjusted Odds Ratios With 95% Confidence Intervals (CIs) For Not Participation In Cervical Cancer Screening

	Odds Ratio	95% CI
Unadjusted model
HPV vacinations status
Vaccinted	Reference
Un-vaccinated	2.5	(2.3-2.7)
Adjusted model^a
HPV vacinations status
Vaccinted	Reference
Un-vaccinated	2.1	(1.9-2.3)
Socio-economic factors^b
Parental civil status
Married/cohabiting	Reference
Single	1.0	(0.9-1.1)
Individual area of residence
Densley populated	Reference
Intermediate populated	0.9	(0.9-1.0)
Thinly populated	0.8	(0.8-0.9)
Individual country of origin
Denmark	Reference
Western countries	1.4	(1.0-1.8)
Non-western countries	3.6	(3.2-4.0)
Parents highest education
High	Reference
Middle	1.1	(1.0-1.2)
Low	1.3	(1.2-1.5)
Family income
High	Reference
Middle	1.2	(1.2-1.3)
Low	1.5	(1.4-1.6)
Parents higest occupation
Working	Reference
Temporarely not working	1.3	(1.3-1.5)
Permenantly not working	1.2	(1.0-1.4)

Notes: ^aOdds ratios are adjusted for parental civil status, highest parental educational level, highest parental occupation, family disposable income, area of residence, and country of origin. ^bSocio-economic factors used in the adjusted model, with OR for each variable’s association with non-participation in cervical cancer screening.

Table 3 Models Testing The Interaction By Country Of Origin (Model 1) And Highest Parental Education (Model 2) On The Association Between Non-vaccination And Cervical Cancer Screening Non-participation

Screening Non-Participation	Total n	Adjusted ORs	95% CI			p-value^a
Interaction model 1
HPV vaccination & country of oigin
Denmark	22,271	2.2	2.0	2.4
Western countries	225	1.3	0.6	2.8		0.019
Non-western countries	2,316	1.5	1.1	2.0
Interaction model 2
HPV vaccination & parents’ highest edducation
High	8,152	1.9	1.6	2.3
Middle	12,806	2.3	2.0	2.6		0.141
Low	3,644	1.8	1.5	2.2

Notes: ^aWald test for interaction shows if the association between non-vaccination and non-screening is modified by country of origin and parental educational level.