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Application of the case-crossover design to reduce unmeasured confounding in studies of condom effectiveness

Lee Warner1, Maurizio Macaluso, Harland D Austin

  • 1National Center for Chronic Disease Prevention and Health Promotion, Division of Reproductive Health, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA. dlw7@cdc.gov

American Journal of Epidemiology
|April 1, 2005
PubMed

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