Tsang, K. L., Carlson, L. E., & Olson, K. (2007). Pilot crossover trial of Reiki versus rest for treating cancer-related fatigue. Integrative Cancer Therapies, 6, 25–35.
The study used the Usui method, which is the most common form of Reiki. Time varied but averaged about 45 minutes. The study used a randomized order: Reiki for five consecutive sessions, a one-week washout, and two days of Reiki versus rest for five days with a one-week washout, and then one week of no treatment. The intervention was administered by a Reiki master.
The study was conducted at an unspecified setting in Canada.
The study was a counterbalanced crossover, with eight participants randomized to each order.
About 88% of the participants completed all seven treatments. The effect was 0.56 (Reiki) versus 0.02 (rest) on the FACT-F and 0.27 (Reiki) versus 0.08 (rest) on the FACT-G. The paired t-test for the FACT-F was not significant (p = 0.24). Tiredness decreased daily over time.