HPV vaccination at age 14. The cost falls this year; the health arrives decades later. Move the rate and watch what that does.
| Undiscounted | At this rate | |
|---|---|---|
| Cost per girl | — | — |
| QALYs gained | — | — |
| Retained | — | — |
The Indian Reference Case sets 3% for both costs and outcomes, beyond one year,
and asks you to vary it from 0% to 5% in sensitivity analysis and to report undiscounted values
as well.
Watch the two “retained” figures diverge. The cost is paid now, so discounting barely touches it;
the health arrives from age 30 onward, so it is discounted hard. That asymmetry is not a quirk of
arithmetic. It is why every prevention programme looks worse than a treatment at the same rate,
and it is the reason some economists argue health should be discounted at a lower rate than money.
The counter-argument is that a lower rate for health implies you should always wait, because
delaying a programme makes it look better. Neither side has won.
The figures here are illustrative: a ₹1,500 cost at age 14 and a small annual health gain
from age 30 to 70, chosen to show the mechanism cleanly, not extracted from any paper. Compare
what you get at 3% with the ₹5,693–₹31,511 per QALY that Chauhan and colleagues report for HPV
vaccination in India.