Sample size calculation for active-arm trial with counterfactual incidence based on recency assay

  title={Sample size calculation for active-arm trial with counterfactual incidence based on recency assay},
  author={Fei Gao and David V. Glidden and James P Hughes and Deborah J Donnell},
  journal={Statistical Communications in Infectious Diseases},
Abstract Objectives The past decade has seen tremendous progress in the development of biomedical agents that are effective as pre-exposure prophylaxis (PrEP) for HIV prevention. To expand the choice of products and delivery methods, new medications and delivery methods are under development. Future trials of non-inferiority, given the high efficacy of ARV-based PrEP products as they become current or future standard of care, would require a large number of participants and long follow-up time… 

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