Abstract Background Lower-than-expected incidence of HIV undermines sample size calculations and compromises the power of a HIV prevention trial. We evaluated the effectiveness of interim monitoring of HIV infection rates and on-going modification of recruitment strategies to enroll women at higher risk of HIV in the Cellulose Sulfate Phase III study in Nigeria. Methods We analyzed pr... https://www.roneverhart.com/C7-Corvette-Stingray-Lapel-Pin-Crossed-Flags/