Carry-over bioequivalence

Senn SJ, D Angelo G, Potvin D (2004) Carry-over in cross-over trials in bioequivalence theoretical concerns and empirical evidence. Pharmaceutical Statistics 3 133-142. 

Furthermore, there is empirical evidence that the issue of carry-over in bioequivalence studies is not important. In a study of more than 400 cross-over trials D Angelo et al. (2001) found that significant carry-over effects occurred about as often as might be expected by chance and furthermore that the distribution of P-values was uniform (Senn et al, 2004). For further discussion see Chapter 17. 

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