AHRQ Report The article in the Journal of Alternative and Complementary Medicine 2008 makes a few criticisms of the 2007 Alberta report as follows It mixed mental techniques meditation with those that had a more physical component such as Tai Chi it didn t distinguish well enough between studies with and without good controls criticised studies for not being double blind when that is very tricky with these sorts of experiments and it did not look at effects of meditation on smoking alcohol and drug abuse