The diversity, and apparent impotence, of many meditative practices makes the construction of sham meditation quite feasible since researchers can develop rationales to justify almost any method that approximates the expectations of trial participants.
For instance, Smith’s (1995) RCT compared TM to an imitation exercise designed to closely mimic the entire technique, except for the proprietary mantra. Forty four participants practiced one of the 2 techniques for 24 weeks, with the same instructions for frequency and duration only to find that no difference between the 2 methods was detectable. This study used well validated self-reporting measures shown in other studies to be quite sensitive to the effects of meditative practices.
Similarly Dua (1992) compared a form of meditation that he developed to a “negative thought reduction” method as well as to a “negative thought enhancement placebo” for the management of anger in a small RCT and found no differences between the practices in any of the outcome measures at the end of the treatment period.
On the other hand, Wolf (2003) compared a meditation based on a traditional Sanskrit mantra (the maha mantra) with a pseudo mantra and observed substantial differences in post treatment outcomes.
In smaller trials, Rai (1988, 1993) observed a number of significant differences when he compared Sahaja Yoga meditation to “mimicking exercises” in the treatment of asthma, hypertension and stress.