Randomization and intervention
Randomization lists were assembled by the Emory University data management core and assignments were sent to the participating international research centers in sealed tamper-proof envelopes. Assignments were stratified into two sites in India and six sites in Peru. Eligible participants were randomized into intervention and control arms by selecting one of six envelopes presented to them by trained study field staff visiting their homes. The intervention households received a locally available LPG stove as well as continuous supply and delivery of free LPG fuel for 18 months during the study. Exclusive stove use during fuel deliveries was encouraged and reinforced by field staff and details of the behavior change program have been previously published (