KnowraPlacebo-controlled trialLinked fromLinked fromThe 15 pages that link to Placebo-controlled trial, each with the reason it gives.All 15Broader topic 2Related 10Narrower topic 1Compared with 2Blinded experimentCompared with: A placebo comparison can support participant masking, unlike many active-control comparisons.Louise HayCompared with: Such trials provide a standard for testing health claims that affirmation practices do not establish on their own.