Table 1.
Variables | Alternative values |
---|---|
Background risk of cervical cancer mortality | 5.0/7.5/10 per 100 000 |
Past screening (cytology) | Yes/No |
Sensitivity (probability of at least ASCUS) of cytology for CIN grade25: | |
CIN grade I | 40/32 |
CIN grade II | 50/40 |
CIN grade III or worse | 75/60 |
Probability of at least HSIL for CIN grades: | |
CIN grade I | 4/3 |
CIN grade II | 19/15 |
CIN grade III or worse | 47/38 |
Specificity of cytology (for CIN grade I or worse) | 97/98.5 |
Sensitivity of HPV test (for high risk HPV infection)24 | 90/95 |
Prevalence of HPV in CIN grade I or less* | Low/High |
Laboratory costs (€) HPV screening | 21/33 |
Total cost (€) cytology | 26/52 |
Threshold value (€) for cost effectiveness | 20 000/30 000/50 000 per QALY gained |
€1.00 (£0.84; $1.31).
See table 2 for rounded up values for laboratory costs of screening and total cost of cytology.
ASCUS=atypical squamous cells of undetermined significance; CIN=cervical intraepithelial neoplasia; HSIL=high grade squamous intraepithelial lesion; QALY=quality adjusted life year.
*Depends on background risk of cervical cancer mortality. On top of increased HPV prevalence associated with a higher background risk, to account for the possibility of a country with a high prevalence of HPV, the number of women with a positive HPV test result and without cytological abnormalities was multiplied by a factor of 2. If the background risk was 5 deaths per 100 000 life years, the mean prevalence of HPV in the total population would be 6% in the case of high prevalence and 3% in the case of low prevalence; if the background risk was 7.5 deaths per 100 000 life years, the mean prevalence in the total population would be 8% or 4%; and if the background risk was 10 deaths per 100 000 life years, the mean prevalence in the total population would be 10% or 5%.