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 included 16 participants, including 13 women and 12 Caucasians, all with varying cancer types and times since chemotherapy.
• Median age was 59 years (range 33–84 years). 
• Patients were included if they had fatigue greater than 3 on 0-to-10 scale, understood English, and were living at home.
• Patients were undergoing long-term follow-up, but it was unclear how long it had been since chemotherapy was completed.

The study was conducted at an unspecified setting in Canada.

The study was a counterbalanced crossover, with eight participants randomized to each order.

• Functional Assessment of Cancer Therapy–Fatigue (FACT-F)
• FACT-General (FACT-G), before and after each period (Reiki or rest) 
• Edmonton Symptom Assessment Scale (ESAS), daily before and after treatment

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.

• No analysis of order effect was conducted.
• The study had a small sample size.
• Multiple diagnoses, stages, and treatments were included.
• Analysis did not look at interaction effect.
• There was a problem with the inclusion criteria:  the range of time from diagnosis was 3 days to 3.79 years.