In the double-blind, randomized control trial, half the women got tenofovir gel and half got a placebo.

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The investigators are now conducting a randomized, controlled clinical trial of RAGE Control in the outpatient clinic at Boston Children's that adds a cooperative component.

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The gold standard for testing medical treatments is the randomized trial, in which patients are randomly assigned to a treatment or control group to spread patient differences evenly and avoid bias in results.

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