Systematic Review of Energy Healing for Cancer Provides Little Concrete Guidance

Abstract & Commentary

By Dónal P. O'Mathùna, PhD. Dr. O'Mathùna is Senior Lecturer in Ethics, Decision- Making & Evidence, School of Nursing, Dublin City University, Ireland; he reports no financial relationship to this field of study.

Synopsis: This systematic review searched for studies using any methodology that measured outcomes in cancer patients who received energy healing techniques. Some evidence of improvements in psychosocial outcomes was found, but the methodological deficiencies in the original studies undermined confidence in their findings. The reviewers call for further research studies designed according to high-quality research standards.

Source: Agdal R, et al. Energy healing for cancer: A critical review. Forsch Komplementmed 2011;18:146-154.

This article describes a systematic review of the efficacy and effectiveness of various "energy healing" therapies used for cancer patients. Complementary and alternative medicine (CAM) commonly uses the term "energy healing" and applies it to a wide variety of therapies. The therapies examined in this systematic review were Reiki, therapeutic touch (TT), and healing touch.

An extensive search was conducted of the medical and psychological literature from 1998 to 2010. The inclusion and exclusion criteria were clearly described. The reviewers identified 147 articles in PubMed, with no additional studies located in the other databases searched. All but eight of these articles were excluded with explanations given. Of these, six were quantitative studies and two were qualitative studies of the efficacy and effectiveness of energy healing for cancer patients.

All eight studies were summarized in tables and discussed in narrative format. A meta-analysis was not possible because different energy therapies were employed, and even when the same outcomes were measured, different tools were used. The studies used a wide variety of methodologies, primarily focused on relieving symptoms such as pain, fatigue, depression, anxiety, or nausea. Six studies measured pain outcomes, with three reporting significant relief after receiving energy healing (P = 0.03, 0.002, and 0.0001, respectively). Two of these were randomized controlled trials. The third was intended to be randomized, but patients refused assignment to standard care and the trial was stopped after accruing one-fourth of the patients planned. Two other studies reported no significant changes in pain, and a qualitative study found that people reported reduced pain after TT. Overall, the reduction in pain was roughly 1 on a 10-point visual analogue scale (VAS). This finding is in keeping with a reduction of 0.83 (95% confidence interval -1.16 to -0.50) on a 10-point VAS found in another meta-analysis of touch therapies for pain.1

One study found that fatigue decreased significantly while another found only a non-significant reduction. Studies that measured nausea found no changes. Use of pain medication and other measures such as heart rate and blood pressure did not change significantly. In qualitative interviews, people reported improved feelings of well- being after energy therapies, but quantitative measurements found varying outcomes.

The reviewers assessed the methodological quality of the studies using the SIGN quality scale (Scottish Intercollegiate Guidelines Network).2 None of the studies included in the review met the criteria for high standards that would produce reliable results. Three studies achieved an overall positive rating, meaning that they met some of the criteria expected of high-quality studies, implying that the conclusions would be unlikely to change if the remaining quality standards had been achieved. The other five studies had overall negative ratings, meaning that few or none of the methodological standards were attained. Therefore, the conclusions would likely or very likely change if the methodology employed was improved upon.

Study weaknesses centered around numbers of subjects, blinding, and conflation of roles of healer and researcher. A total of 531 subjects were involved in the eight trials, with individual trials involving from 7 to 230 participants. Only one study reported adequate blinding. Another study began as a single-blind trial, but the healer unblinded himself during the trial (and quit his role). The trial ended up as a descriptive study. In at least three studies the investigator was also the healer, raising concerns about potential bias.

In spite of poor study quality, the reviewers note that the results are interesting enough to warrant further research. Future studies should strive to use high-quality research standards. The energy modalities used are complex and raise challenges for researchers; however, some of the studies reviewed demonstrate that rigorous research methodologies are possible with energy therapies.

The authors concluded that few studies have examined the effects of energy healing in cancer patients "and none of them are of a size or quality that allows reliable conclusions to be drawn."


This systematic review was conducted well in many regards. The search strategy was described in detail, using many relevant terms, but the term "energy" was not used. This omission was not explained, although it likely would have led to numerous articles addressing more conventional understandings of energy. The authors searched from 1998 forward without explaining why this date was chosen. At least one study of Reiki in cancer was missed because of this.3 Although a number of electronic databases were searched, specific CAM databases were not used such as that within the Cochrane Library. The fact that no additional studies were found in databases other than PubMed would suggest that their choice of databases was not optimal. They also restricted their search to peer-reviewed literature. This would be expected to identify higher quality studies, but they may have missed some suitable studies. On the other hand, no restrictions were placed on the study methodologies which ensured that a broad range of studies were included. Both qualitative and quantitative studies were reviewed. The most consistently measured outcome was pain level. While some trials reported significant pain reduction, the effect size was modest.

Energy healing therapies like TT have been studied in controlled trials since the 1970s. This review demonstrates that their methodological quality continues to be a significant problem. At the very least, interventions should be described fully so that readers can identify which therapies are being investigated. Full blinding is not possible given that the healers must know what they are doing. However, those measuring outcomes should be blinded to group allocation. This is particularly important given that these therapies are usually recommended for symptoms like pain and well-being, which are strongly influenced by the placebo effect. For these reasons, the regular use of investigators as healers is particularly problematic in these trials.

In addition, patients can be blinded in these studies by using sham therapies or waiting list controls. Such controls are challenging, though, because of disagreement over the mechanisms of energy therapies. Different proposals are made for suitable controls based on hypotheses that some non-physical energy, healers' intentions, patients' expectations, or various hand movements are central.

Currently, firm conclusions about the efficacy or effectiveness of energy healing are not supported by the research studies reviewed in this article, in spite of claims, for example, that therapies like Reiki are research-supported.2 Until researchers adopt rigorous methods, questions will remain about the effectiveness of energy therapies, and until the results of more rigorous research are available, energy therapies should not be added to clinical practice in general. However, given their popularity, it is likely they will continue to be used by patients based on uncontrolled observation of therapeutic benefits.


1. So PS, et al. Touch therapies for pain relief in adults. Cochrane Database of Systematic Reviews 2008; Art. No.: CD006535.

2. Harbour R, Miller J. A new system for grading recommendations in evidence based guidelines. BMJ 2001;323:334-336.

3. Toms R. Reiki therapy: A nursing intervention for critical care. Crit Care Nurs Q 2011;34:213-217.