Transcription of Sample Size Calculations for Randomized Controlled Trials
{{id}} {{{paragraph}}}
Sample size Calculations for Randomized Controlled TrialsJanet WittesINTRODUCTIONMost informed consent documents for Randomized con-trolled Trials implicitly or explicitly promise the prospectiveparticipant that the trial has a reasonable chance of answer-ing a medically important question. The medical literature ,however, is replete with descriptions of Trials that providedequivocal answers to the questions they addressed. Papersdescribing the results of such studies may clearly imply that thetrial required a much larger Sample size to adequately addressthe questions it posed. Hidden in file drawers, undoubtedly, aredata from other Trials whose results never saw the light ofday some, perhaps, victims of inadequate Sample size .
The literature contains some general reviews and discus-sions of sample size calculations, with particular reference to controlled trials (2–8). GENERAL CONSIDERATIONS Calculation of sample size requires precise specification of the primary hypothesis of the study and the method of analysis. In classical statistical terms, one selects a null
Domain:
Source:
Link to this page:
Please notify us if you found a problem with this document:
{{id}} {{{paragraph}}}