Thrane & Cohen, (2014)

The authors of this study appear to believe, as I do, that quantum physics may “hold promise in the future explanation of the mechanisms of Reiki” (Thrane & Cohen, 2014, p. 3). Their study speaks to the human biofield and the difficulty experienced in measuring it while noting that the human body produces very measurable electrical and magnetic fields and that EKG’s and MRI’s work with these fields to produce common medical tests. What may have been unmeasurable 100 years ago can be precisely monitored today, so there is reason to believe sublte energy fields will one day be accurately measured.

Outcomes for anxiety showed lower “relaxation response therapy compared to wait-list control for men with prostate cancer receiving radiation therapy”, and for chemotherapy patients, “Tsang et al. (2007) found within group differences for a decrease in anxiety (p<.005) and a large effect size (d=.83) for subjects in the Reiki therapy treatment arm when measured prior to the first Reiki therapy treatment, compared with following the last Reiki therapy treatment in a group of cancer patients on standard opioid therapy" (p. 6). For outpatients "Richeson et al. (2010) found a significant decrease in anxiety (p=.0005) and a large effect size (d=2.08) within the Reiki therapy intervention and a significant increase in anxiety (p=.0313) and a large effect size (d= −.208) within the control group while investigating the use of Reiki therapy with community-dwelling older adults. When calculating between group differences post Reiki therapy intervention, there was a very large between group difference when comparing the Reiki therapy group to the control group (d= −4.5)" (p.7). Regarding outcomes for pain "A Reiki therapy intervention used with cancer patients found a significant between group decrease in pain (p=.035) and a medium effect size (d=.64) on day one of the intervention and a significant between group decrease in pain (p=.002) and a large effect size (d=.93) for opioids plus Reiki therapy when compared to opioids plus rest on day four of the intervention (Olson et al., 2003). Cancer patients in the Tsang et al. study who had recently completed chemotherapy realized a significant decrease in pain (p<.05) and a medium effect size (d=.76) for within group measures when comparing scores from before the first Reiki treatment to after the final Reiki treatment." Of equal interest, comparing the Reiki therapy and usual care groups, the women in the Reiki therapy intervention took less pain medication at T2 (p=.001, d=1.82), T3 (p=.007, d=1.29), and T6 (p=.04, d=.81) with large to very large between group effect sizes." And finally, "Comparing a Reiki therapy intervention with a wait list control group of community dwelling older adults, there was a significant within group decrease in pain (p=.0078) and a large effect size (d=2.08) and a significant within group increase in pain (p=.0156) and a large effect size (d= −2.08) for the wait list control group (Richeson et al., 2010). Because of the decrease in pain for the Reiki therapy group and corresponding increase in pain for the control group, the calculated effect size for the between group difference was very large (d=4.5)" (p. 7). I find it interesting that women had more positive results than men in the study noted above, however, my own experience is that women tend to be more open than men to the subject of energetics and biofield therapy. References:

Thrane, S., & Cohen, S. M. (2014). Effect of Reiki Therapy on Pain and Anxiety in Adults: An In-Depth Literature Review of Randomized Trials with Effect Size Calculations. Pain Management Nursing: Official Journal of the American Society of Pain Management Nurses, 15(4), 897–908. http://doi.org/10.1016/j.pmn.2013.07.008