Table 4. Outcomes under baseline assumptions. Incremental cost–effectiveness ratios represent the cost for every year of life gained by adopting the more expensive option in favour of the next cheapest, nondominated option.

Options in order of increasing cost	Average lifetime cost of screening and treatment (discounted at 3.5% p.a.)	Average life expectancy from age 15 years (discounted at 3.5% p.a.)	Incremental cost–effectiveness ratios	Total deaths averted	CIN 2/3 detected per lifetime	Inappropriate referrals for colposcopy per lifetime
No screening	£86.14	25.292	—	—	—	—
Repeat cytology with LBC, 5 years	£159.79	25.316	ED	64.89%	0.152	0.084
HPV triage with LBC, 5 years	£162.54	25.317	£3,067	67.63%	0.157	0.099
Repeat cytology without LBC, 5 years	£166.06	25.316	D	64.89%	0.152	0.083
Primary HPV with LBC, 5 years	£169.50	25.319	£3,720	71.29%	0.156	0.390
HPV triage without LBC, 5 years	£170.38	25.317	D	66.72%	0.157	0.099
Primary HPV without LBC, 5 years	£187.72	25.318	D	68.55%	0.150	0.367
Repeat cytology with LBC, 3 years	£214.59	25.320	ED	73.12%	0.170	0.132
HPV triage with LBC, 3 years	£219.23	25.321	ED	74.95%	0.175	0.158
Combined cytology and HPV with LBC, 5 years	£219.50	25.321	£22,628	77.69%	0.166	0.515
Repeat cytology without LBC, 3 years	£224.13	25.320	D	72.20%	0.170	0.131
Primary HPV with LBC, 3 years	£227.87	25.321	ED	74.03%	0.153	0.613
HPV triage without LBC, 3 years	£231.17	25.321	D	74.03%	0.175	0.157
Primary HPV without LBC, 3 years	£256.01	25.320	D	70.38%	0.147	0.574
Combined cytology and HPV with LBC, 3 years	£309.58	25.323	£37,846	80.43%	0.160	0.810

D=dominated; ED=extended dominated; LBC=liquid-based cytology; HPV=human papillomavirus.