Table 1.

Marginal type-specific risk of progression to CIN3+ of incident and prevalent single-type HPV infections, over 7 years of follow-up.

Length of infection	HPV type1	Single-type HPV infections2
		Frequency	CIN3+ cases3		Cumulative risk of CIN3+ (%)
			Total	Detected at baseline	Yr 0	Yr 1	Yr 3	Yr 5	Yr 7
Prevalent	16	1907	664	430	18.2	20.4	23.3	24.1	24.7
	33	130	42	28	16.1	18.7	20.0	20.5	20.9
	18	520	102	60	8.1	9.0	10.2	10.9	11.0
	58	324	60	46	8.4	9.1	10.0	10.6	10.8
	31	949	149	89	6.7	7.4	8.9	9.3	9.4
	35	261	39	19	5.5	7.0	7.9	8.8	9.1
	52	1073	130	73	4.6	5.2	6.5	6.7	6.9
	45	371	50	35	5.3	5.7	6.3	6.7	6.8
	39	268	20	13	2.7	3.2	3.8	3.9	3.9
	56	253	14	11	2.2	2.2	2.4	2.6	2.7
	51	603	30	15	1.6	1.9	2.5	2.6	2.6
	68	174	7	3	0.8	1.3	1.9	2.1	2.1
	59	189	8	4	1.3	1.6	1.9	2.0	2.0
	Prevalent Total	7022	1315	826 (62.8%)
Incident	16	472	87	42	6.2	7.8	9.6	10.8	10.9
	33	44	8	5	7.6	9.2	11.0	11.1	11.1
	18	176	27	16	5.6	6.2	7.1	7.8	7.9
	58	91	6	6	3.3	3.3	3.3	3.3	3.3
	31	299	21	10	2.4	2.6	3.0	3.4	3.5
	35	71	5	4	3.8	3.8	3.8	3.8	3.8
	52	321	15	8	1.6	1.7	2.2	2.4	2.4
	45	143	11	5	2.2	2.4	3.1	3.8	4.0
	39	85	5	3	2.1	2.5	2.8	2.8	2.8
	56	103	3	0	0.0	0.7	0.9	0.9	1.2
	51	287	10	3	0.7	0.9	1.4	1.6	1.7
	68	55	4	3	3.4	3.4	3.4	3.4	3.4
	59	66	2	0	0.0	0.1	0.8	1.6	1.8
	Incident Total	2213	204	105 (51.5%)
All infections	Total	9235	1519	931 (61.2%)

¹Ordered based on descending risk of CIN3+ for prevalent (most common) single type infections.

²Risk estimates restricted to single-type HPV infections.

³Average time to end of follow-up was 4.1 years for prevalent infections and 4.9 years for incident ones.