OJPsych  Vol.5 No.2 , April 2015
Problems with Double Blind in Medicine
Abstract: Double blind tests of drugs and procedures depend on obtaining two equal and randomly assigned groups to be compared. With a diagnosis based only on symptoms, but with different etiologies, this is not very likely. We here show the probability of obtaining two equal groups with one diagnosis but three etiologies. The mathematical name for such a problem is multivariate hypergeometric distribution. We find that increasing the group size decreases the probability.
Cite this paper: Reichelt, Y. and Reichelt, K. (2015) Problems with Double Blind in Medicine. Open Journal of Psychiatry, 5, 204-206. doi: 10.4236/ojpsych.2015.52024.

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