Clinical Trials 2008; 5: 273–276INTERNATIONAL Balancing science and community concerns in

Background The methods and purposes of randomization are often poorly understood by participants in clinical trials. Individual misunderstandings can be compounded in community-based intervention trials, especially in research-naı̈ve communities. Randomizing entire communities to intervention or control status risks creating the perception that control communities are being denied desirable services, ultimately undermining trust in the research process. Purpose To develop a randomization scheme for an HIV prevention trial of a community-level intervention that would be credible to the communities involved while maintaining the scientific integrity of the intervention trial at a rural site in Zimbabwe. Methods Project staff developed strong partnerships with community stake-holders and embedded randomization into the trial’s community preparedness processes. Local idioms were used to explain the concept, purpose, and mechanics of randomization. Actual allocation of communities to intervention or control status took place at a public lottery conducted by local chiefs. Results The Project obtained the endorsement of its randomization of eight rural communities by local political stakeholders and community members. Limitations This case study may not generalize to other settings. Conclusions By developing strong community partnerships, and communicating randomization through local idioms, community based intervention trials con-ducted in resource-poor environments can successfully mitigate risks inherent in randomizing communities to control status. Clinical Trials 2008; 5: 273–276