My original query was:
I was asked to help in designing a trial for the assessment of the
equivalence of two treatments with a binary outcome. Can anybody give me
any pointer on how to properly define the difference between the
expected proportions for sample size calculation in this case where the
expected proportions are the same? Is there a way to formally define a
meaningful standardized distance in this case?
Let me thank P.R. Swanks, J. Jeffs, J. Huges, A. Shaffrath Rosario, M
Guerriero for helpful comments and references. Relevant references included:
Farrington and Manning (1990; Stat in Med)
and a corresponding letter to the editor by Schoder et al., Stat in Med
2002, 21: 1958-1960.
Jones B, Jarvis P, Lewis JA, Ebbutt AF. Trials to assess the
equivalence: the importance of rigorous methods. BMJ 1996;313:36-9.
Cohen, J. (1988). Statistical Power Analysis for the Behavioral Sciences
(2nd ed.). Hillside, NJ:Erlbaum.
Machin and Campbell's book of tables.
--
Alessio Pollice
Dipartimento di Scienze Statistiche
Università degli Studi di Bari
Via C. Rosalba 53
70124 Bari, ITALY
Tel.: +39 080 5049243
Fax: +39 080 5049147
e-mail: [log in to unmask]
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