Net costs: difference between investment costs of the programme (testing, pharmacotherapy for mother and child, caesarean section and bottle-feeding) and the financial benefits of the programme (preventing HIV/AIDS care for infected children).
No screening, i.e. 90% breastfeeding and natural delivery, was compared to screening, i.e. screening and pharmacotherapy, caesarean section and bottle-feeding for all seropositive pregnant women (100% compliance and acceptance of caesarean section and bottle-feeding).
The cost-effectiveness ratio was net costs per LYG. LYG were not discounted in the basic assessment (only in sensitivity analyses).
1. Prevalence of 5 undiagnosed HIV-infections per 10,000 pregnant women:
Investment costs: Dfl 225,000; financial benefits: Dfl 132,000 (assuming life long care costs of Dfl 100,000)/Dfl 661,000 (assuming life long care costs of Dfl 500,000); Net costs: Dfl 93,000 (assuming life long care costs of Dfl 100,000)/Dfl -436,000 (assuming life long care costs of Dfl 500,000). Break-even point for life-long care (net costs are Dfl 0): Dfl 171,000.
2. Prevalence of 10 undiagnosed HIV-infections per 10,000 pregnant women:
Investment costs: Dfl 301,000; financial benefits: Dfl 265,000/Dfl 1,323,000; Net costs: Dfl 36,000/Dfl -1,022,000. Break-even point for life-long care: Dfl 114.000
3. Prevalence of 15 undiagnosed HIV-infections per 10,000 pregnant women:
Investment costs: Dfl 376,000; financial benefits: Dfl 397.000/Dfl 1,984,000; Net costs: Dfl -20,000/Dfl -1,608,000. Break-even point for life-long care: Dfl 95,000
If the life-long costs for care are Dfl 100,000, the net costs per LYG are Dfl 225 (prevalence of 10 per 10,000 pregnancies) or Dfl 1,160 (prevalence of 5 per 10,000 pregnancies).
Sensitivity analyses:
1. Doubling the screening costs per pregnant woman (test procedure and education), assuming a prevalence of 10 undiagnosed HIV-infections per 10.000 pregnancies and life-long care costs for HIV-infected children of Dfl 100,000: Net costs per LYG: Dfl 994 (compared with Dfl 225).
2. More conservative estimates for the effectiveness of preventative interventions (using the lower boundary of the CI for transmission-chances without pharmacotherapy, caesarean section and bottle-feeding, and the upper boundary of the CI for transmission-chances with these interventions): Net costs per LYG: Dfl 1,050 (compared with Dfl 225).
3. Discounting LYG at 4%: Net costs per LYG: Dfl 1,160 (compared with Dfl 225).
4. A 50% reduction in compliance and acceptance of caesarean section: Net costs per LYG : Dfl 1,050 (compared with Dfl 225).
In all sensitivity scenario's HIV-screening would be cost-effective if the life-long care costs for an HIV-infected child were more than Dfl 164,000.