Double dummy technique

Fig. 2.7 The double-dummy technique. The patient always takes a tablet and a capsule. In treatment A, the tablet contains the active drug and the capsule contains the placebo. In treatment B, the capsule contains the active dmg and the tablet contains the placebo.

Double dummy technique. A means of achieving blinding (masking) in clinical trials where two active treatments are being compared and when (as is nearly always the case) they cannot be matched. A placebo to each is then employed and patients are allocated to receive either A and placebo to B or B and placebo to A. 

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