The challenge
Malaria killed many children, and too few families slept under insecticide-treated nets.
The case
A common argument in global health was that people value and use what they pay for, so aid products like insecticide-treated bednets should be sold, not given away. Researchers tested this with pregnant women at prenatal clinics in Kenya, randomly varying the price of bednets. Even small prices sharply reduced uptake, while women who got nets free were just as likely to use them as those who paid. The findings supported a global shift toward mass free distribution of nets. In the experiment, uptake of bednets dropped by 75 percent when the price rose from zero to $0.75, the price then charged to pregnant women in Kenya.
Why it worked
A plausible theory turned out to be wrong when tested. Free distribution reached far more people at risk without reducing use.
Sources
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