Overuse of medical care is often attributed to an informed expert problem, whereby doctors induce patients to purchase unnecessary treatments. Alternatively, patients may drive overuse of medications by exerting pressure on doctors to overprescribe, undermining the doctor's gatekeeping function...

We investigate the mechanisms underlying health promotion campaigns designed to eliminate open defecation in at-scale randomized field experiments in four countries: India, Indonesia, Mali, and Tanzania. Health promotion works through a number of mechanisms, including: providing information on...