Friday, June 12, 2009

Double Dummy Technique











Double dummy is a technique for retaining the blind when administering supplies in a clinical trial, when the two treatments cannot be made identical. Supplies are prepared for Treatment A (active and indistinguishable placebo) and for Treatment B (active and indistinguishable placebo). Subjects then take two sets of treatment; either A (active) and B (placebo), or A (placebo) and B (active).

Double dummy is a method of blinding where both treatment groups may receive placebo. For example, one group may receive Treatment A and the placebo of Treatment B; the other group would receive Treatment B and the placebo of Treatment A.

The figure on the left side is a double-dummy example for a two treatmetn arm scenario. The figure on the right side is a double-dummy example for a three-arm scenario. To maintain the blinding, subjects in each arm will take one tablet and one capsule. In the example on the right side table, subject in placebo arm will take one placebo tablet and one placebo capsule.

15 comments:

  1. thank you very much for the lesson :)

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  2. Thanks, this was pretty useful!

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  3. Anonymous11:49 AM

    love the pictures. It's helpful. thank you.

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  4. You've made it pretty much easy to understand. Thank you a lot!

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  5. Anonymous12:32 PM

    This made so much sense thank you so much x

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  6. that was very easy and understandable explianation

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  7. Thank you for your explanation, it was the simplest and most useful source to explain the double dummy design

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  8. Anonymous4:41 PM

    Very helpful indeed.First time I have got my head around it clearly!

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  9. I am a translator, and I would like to know if the staff administering the treatment knows which patient is getting a double placebo therapy.

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  10. Very helpful! Thank you.

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  11. What is the advantage of three arm double dummy study design?

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  12. Anonymous4:05 AM

    Very helpful. Thank you very much

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  13. Great article thanks for sharing this great article

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  14. Anonymous5:25 AM

    Thank you very much! this is a fantastic answer.

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