The Centre for Infectious Disease Research in Zambia (CIDRZ) and researchers from the University of North Carolina at Chapel Hill (UNC) have partnered to pilot an peer-referral incentive program to increase voluntary medical male circumcision (VMMC) uptake in Zambia. The program allows each man coming for circumcision to refer up to 5 uncircumcised men in their social network for VMMC services and receive a monetary reward for each successful referral. The peer-referral program offers several advantages over traditional demand-creation approaches that rely on employing mobilizers or community health workers (CHWs). The amount of the monetary incentive will be analogous to the amount of incentive that CHWs might receive for comparable effort, making the program suitable for large-scale expansion. The effect of the peer-referral program on uptake of VMMC services will be evaluated using a rigorous methodology proposed by UNC researchers.

The investigators propose a cluster randomized design in which the CIDRZ-supported VMMC clinics in the Southern Province in Zambia will be randomly selected to have a peer referral incentive program or not. In approximately 10 randomly selected intervention clinics, all men who reside in the catchment area of the clinic and come for male circumcision services will be eligible to receive 5 referral vouchers that will entitle them to receive monetary compensation for each voucher that is subsequently presented by a man who comes to the clinic and undergoes male circumcision. In 10 remaining clinics (control group), VMMC services will proceed as per the current standard of care, without peer referral incentives. All clinics including those allocated to the control group will have the standard mobilization and promotion activities that are used by CIDRZ.

In intervention clinics:

• All eligible men seeking VMMC in intervention clinics will be asked if they want to participate in the study. This can happen on the day of the circumcision or within 7 days after the circumcision.
• If yes, a file is open for them as "referring person". They receive 5 vouchers. They also receive MC brochures to distribute to friends.
• As his friends or relatives come in as referrals, they are written in his file He can then claim reimbursement any time between the time a referred friend comes for VMMC and the expiration of the voucher. The referring person needs to bring the voucher in order to receive reimbursement.
• Friends who come as referrals are given the possibility to become referring persons too, if within the intervention period. In that case, a new file is open for them as "referring persons".

Inclusion Criteria:

• Inclusion criteria for receiving vouchers: Uncircumcised men 18-49 years old seeking VMMC services and undergoing male circumcision at one of the clinics selected for the study during the 5 months of the active intervention.

Inclusion criteria for a successful referral: The referred person needs to be a previously uncircumcised man 18-49 and seeking VMMC services at that clinic during the 3 months of eligibility for voucher redemption.

Exclusion Criteria:

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