Vaccination Reminders and Incentives — India
J-PAL / Seva Mandir · Rajasthan, India · 2010
Summary
Banerjee and Duflo's vaccination study found that a reliable, predictable schedule alone nearly tripled immunization rates, and adding a small incentive (worth about $0.75) increased them sixfold. The finding challenged the assumption that low immunization rates in rural India reflected vaccine hesitancy — most parents wanted to vaccinate but faced coordination problems (not knowing when camps would be held) and procrastination. The lentil incentive addressed both by giving parents an immediate benefit and a concrete date to plan around. The result is one of the most cited demonstrations of how behavioral frictions, not preferences, drive low take-up of beneficial programs.
Research question
"Do reminders and small incentives increase childhood immunization rates in rural India?"
Methodology
Intervention
Three arms: reliable immunization camp schedule (information only), reliable schedule plus small incentive (1 kg lentils per immunization), control (status quo)
Assignment
Randomized controlled trial (village-level)
Sample size
134 villages; 1,640 children
Primary outcome
Full immunization rate by age 2
Effect estimate
Control: 6% fully immunized; reliable schedule only: 17%; schedule plus lentil incentive: 38%
Decision
India's immunization program incorporated reliable scheduling; WHO cited findings in global immunization strategy
Result
Positive
Control: 6% fully immunized; reliable schedule only: 17%; schedule plus lentil incentive: 38%
Evidence strength
Strong
Randomized controlled trial with large sample.
Replication status
Partially replicated
Institution
J-PAL / Seva Mandir
Location
Rajasthan, India
Year
2010
Policy area
Public Health
Mechanism
Information