Research using distant reiki to reduce pain following an elective C-section, randomised, double-blinded study, Results found pain was not significantly different in the distant reiki and control groups, no significant differences in opioid consumption or rate of healing; however, the distant reiki group had a significantly lower heart rate post surgery.
Although I thought this was disappointing, there are many different ways to send distant reiki and some are most likely more effective than others, so in this respect there would need to be more research using different techniques. Reiki practitioners also vary in their methods and training, so this indicates more research is required. It could be that this particular practitioners method was very good for relaxation but not for healing or pain relief.