Table 1

Baseline values and ranges for sensitivity analysis*

Baseline valueSensitivity analysis
Screening and treatment parameters
Screening age(s)5 11 1x: age 39 years;
3x: ages 30, 40 and 50 years;
5x: ages 30, 35, 40,45 and 50 years
Population coverage70.0%40.0%–100%
Uptake of self-collected HPV testing11 99.2%
Uptake of VIA11 48.4%
Proportion of women successfully contacted over phone with HPV test results11 63.0%46.6%–90.0%
Proportion of contacted HPV-positive women attending the clinic11 97.1%
Compliance for all other visits85.0%0%; 40.0%
Proportion of eligible women receiving cryotherapy following positive VIA11 78.6%
Proportion of eligible women receiving cryotherapy following positive HPV test11 78.6%
Proportion of women receiving treatment following colposcopy85.0%
Proportion of women who refuse cryotherapy then return at a later date11 37 0.0%52.0%
Test sensitivity/specificity for CIN2+
 HPV (self-collected)6 77.0%/82.0%100%/100%
 VIA (primary screen)6 31 73.6%/66.6%41.4%/94.5%
 VIA (triage test)6 32 33 73.6%/66.6%36.4%–81.9%/
Test sensitivity/specificity for CIN1+, colposcopy1095.0%/51.0%
Eligibility for cryotherapy34–36
 No lesion90.0%72.2%–92.7%
Cryotherapy effectiveness at the clinic38 44 81.0%70.0%–92.0%
Cryotherapy effectiveness at the referral centre44 81.0%70.0%–92.0 %
Proportion of women who retain HPV infection following cryotherapy10.0%
Cost parameters, women’s time costs
 Women’s time cost, per hour30 US$0.46
 Self-collection of HPV sampleUS$0.19
 VIA screenUS$1.38
 Cryotherapy with no VIA (Kisenyi)US$1.46
 Extra time for cryotherapy post-VIAUS$0.03
 Colposcopy and biopsyUS$2.76
 Cryotherapy (Mulago National Referral Hospital)US$2.76
Cost parameters, programmatic costs†
 Programmatic cost per women screenedUS$6.58
Cost parameters, direct medical costs§
 Self-collected HPV test10 11 45 US$12.73US$34.08
 Cost per cryotherapy10 45 US$5.85US$27.37
 Cost per colposcopy and biopsy11 US$52.25
Treatment of cancer27 37 46
  • 1x: screening at age 39; 3x: screening at ages 30, 40 and 50; 5x: screening at ages 30, 35, 40, 45 and 50.

  • *Costs are described in greater detail in the technical online supplementary appendix.

  • †Programmatic costs include costs for a programme assistant and a community preparedness campaign.

  • ‡As CIN1 is not actually a health state in the model, colposcopy performance is based on the health state of no lesion, HPV infection, CIN2 or CIN3. A treatment threshold for CIN1 was estimated by weighting colposcopy sensitivity for HPV+ women based on the prevalence of CIN1 among HPV+ women in the Uganda START-UP study.

  • §Base case direct medical costs of HPV testing and cryotherapy were informed by START-UP10 45 due to the ASPIRE trial using HPV genotyping technology at an additional expense (this would not be performed in a non-research setting) and the number of assumptions required for cryotherapy cost amortisation.

  • ASPIRE, Advances in Screening and Prevention of Reproductive Cancers; CIN, cervical intraepithelial neoplasia; HPV, human papillomavirus; VIA, visual inspection with acetic acid.