Experimental Design
The catchment area of the clinic was first divided into 29 enumeration areas as defined by the Malawian National Statistics Office. Each enumeration area was subdivided into a total of 114 neighborhood blocks that were demarcated using roads and rivers as natural dividing lines. Blocks were randomly selected into the study, stratified by enumeration area.
Within each selected block, a household census was conducted in which men aged 18-35 years old, regardless of circumcision status, were identified. In households with more than one eligible man, one man was randomly selected as the target respondent. A baseline survey was conducted with this respondent.
After the survey, the respondent was offered a voucher which randomly varied the amount of the circumcision subsidy from fully free to almost full-price. In addition, half of the respondents received comprehensive information about circumcision and HIV. Those who did not receive the information were simply told about the partner clinic’s services and that male circumcision was available there.