- A chance to test your rules of thumb for quickly evaluating clinical trials of alternative or integrative medicine in prestigious journals.
- A chance to increase your understanding of the importance of well-defined control groups and blinding in evaluating the risk of bias of clinical trials.
- A chance to understand the difference between merely evidence-based treatments versus science-based treatments.
- Lessons learned can be readily applied to many wasteful evaluations of psychotherapy with shared characteristics.
A press release from the University of Michigan about a study of acupressure for fatigue in cancer patients was churnaled – echoed – throughout the media. It was reproduced dozens of times, with little more than an editor’s title change from one report to the next.
Fortunately, the article that inspired all the fuss was freely available from the prestigious JAMA: Oncology. But when I gained access, I quickly saw that it was not worth my attention, based on what I already knew or, as I often say, my prior probabilities. Rules of thumb is a good enough term.
So the article became another occasion for us to practice our critical appraisal skills, including, importantly, being able to make reliable and valid judgments that some attention in the media is worth dismissing out of hand, even when tied to an article in a prestigious medical journal.
The press release is here: Acupressure reduced fatigue in breast cancer survivors: Relaxing acupressure improved sleep, quality of life.
A sampling of the coverage:
As we’ve come to expect, the UK Daily Mail editor added its own bit of spin:
Here is the article:
Zick SM, Sen A, Wyatt GK, Murphy SL, Arnedt J, Harris RE. Investigation of 2 Types of Self-administered Acupressure for Persistent Cancer-Related Fatigue in Breast Cancer Survivors: A Randomized Clinical Trial. JAMA Oncol. Published online July 07, 2016. doi:10.1001/jamaoncol.2016.1867.
Here is the Trial registration:
All I needed to know was contained in a succinct summary at the Journal website:
This is a randomized clinical trial (RCT) in which two active treatments that
- Lacked credible scientific mechanisms
- Were predictably shown to be better than
- A routine care that lacked the positive expectations and support.
- A primary outcome assessed by subjectiveself-report amplified the illusory effectiveness of the treatments.
The original research appeared in a prestigious peer-reviewed journal published by the American Medical Association, not a disreputable journal on Beall’s List of Predatory Publishers.
Maybe this means publication in a peer-reviewed prestigious journal is insufficient to erase our doubts about the validity of claims.
The original research was performed with a $2.65 million peer-reviewed grant from the National Cancer Institute.
Maybe NIH is wasting scarce money on useless research.
What is acupressure?
According to the article
Acupressure, a method derived from traditional Chinese medicine (TCM), is a treatment in which pressure is applied with fingers, thumbs, or a device to acupoints on the body. Acupressure has shown promise for treating fatigue in patients with cancer,23 and in a study24 of 43 cancer survivors with persistent fatigue, our group found that acupressure decreased fatigue by approximately 45% to 70%. Furthermore, acupressure points termed relaxing (for their use in TCM to treat insomnia) were significantly better at improving fatigue than another distinct set of acupressure points termed stimulating (used in TCM to increase energy).24 Despite such promise, only 5 small studies24– 28 have examined the effect of acupressure for cancer fatigue.
Don’t be fooled by references to traditional Chinese medicine (TCM) as a basis for claiming a scientific mechanism.
Chairman Mao is quoted as saying “Even though I believe we should promote Chinese medicine, I personally do not believe in it. I don’t take Chinese medicine.”
Alan Levinovitz, author of the Slate article further argues:
In truth, skepticism, empiricism, and logic are not uniquely Western, and we should feel free to apply them to Chinese medicine.
After all, that’s what Wang Qingren did during the Qing Dynasty when he wrote Correcting the Errors of Medical Literature. Wang’s work on the book began in 1797, when an epidemic broke out in his town and killed hundreds of children. The children were buried in shallow graves in a public cemetery, allowing stray dogs to dig them up and devour them, a custom thought to protect the next child in the family from premature death. On daily walks past the graveyard, Wang systematically studied the anatomy of the children’s corpses, discovering significant differences between what he saw and the content of Chinese classics.
And nearly 2,000 years ago, the philosopher Wang Chong mounted a devastating (and hilarious) critique of yin-yang five phases theory: “The horse is connected with wu (fire), the rat with zi (water). If water really conquers fire, [it would be much more convincing if] rats normally attacked horses and drove them away. Then the cock is connected with ya (metal) and the hare with mao (wood). If metal really conquers wood, why do cocks not devour hares?” (The translation of Wang Chong and the account of Wang Qingren come from Paul Unschuld’s Medicine in China: A History of Ideas.)
A 10-week randomized, single-blind trial comparing self-administered relaxing acupressure with stimulating acupressure once daily for 6 weeks vs usual care with a 4-week follow-up was conducted. There were 5 research visits: at screening, baseline, 3 weeks, 6 weeks (end of treatment), and 10 weeks (end of washout phase). The Pittsburgh Sleep Quality Index (PSQI) and Long-Term Quality of Life Instrument (LTQL) were administered at baseline and weeks 6 and 10. The Brief Fatigue Inventory (BFI) score was collected at baseline and weeks 1 through 10.
Note that the trial was “single-blind.” It compared two forms of acupressure, relaxing versus stimulating. Only the patient was blinded to which of these two treatments was being provided, except patients clearly knew whether or not they were randomized to usual care. The providers were not blinded and were carefully supervised by the investigators and provided feedback on their performance.
The combination of providers not being blinded, patients knowing whether they were randomized to routine care, and subjective self-report outcomes together are the makings of a highly biased trial.
Usual care was defined as any treatment women were receiving from health care professionals for fatigue. At baseline, women were taught to self-administer acupressure by a trained acupressure educator.29 The 13 acupressure educators were taught by one of the study’s principal investigators (R.E.H.), an acupuncturist with National Certification Commission for Acupuncture and Oriental Medicine training. This training included a 30-minute session in which educators were taught point location, stimulation techniques, and pressure intensity.
Relaxing acupressure points consisted of yin tang, anmian, heart 7, spleen 6, and liver 3. Four acupoints were performed bilaterally, with yin tang done centrally. Stimulating acupressure points consisted of du 20, conception vessel 6, large intestine 4, stomach 36, spleen 6, and kidney 3. Points were administered bilaterally except for du 20 and conception vessel 6, which were done centrally (eFigure in Supplement 2). Women were told to perform acupressure once per day and to stimulate each point in a circular motion for 3 minutes.
Note that the control/comparison condition was an ill-defined usual care in which it is not clear that patients received any attention and support for their fatigue. As I have discussed before, we need to ask just what was being controlled by this condition. There is no evidence presented that patients had similar positive expectations and felt similar support in this condition to what was provided in the two active treatment conditions. There is no evidence of equivalence of time with a provider devoted exclusively to the patients’ fatigue. Unlike patients assigned to usual care, patients assigned to one of the acupressure conditions received a ritual delivered with enthusiasm by a supervised educator.
Note the absurdity of the naming of the acupressure points, for which the authority of traditional Chinese medicine is invoked, not evidence. This absurdity is reinforced by a look at a diagram of acupressure points provided as a supplement to the article.
Among the many problems with “acupuncture pressure points” is that sham stimulation generally works as well as actual stimulation, especially when the sham is delivered with appropriate blinding of both providers and patients. Another is that targeting places of the body that are not defined as acupuncture pressure points can produce the same results. For more elaborate discussion see Can we finally just say that acupuncture is nothing more than an elaborate placebo?
Worth looking back at credible placebo versus weak control condition
In a recent blog post I discussed an unusual study in the New England Journal of Medicine that compared an established active treatment for asthma to two credible control conditions, one, an inert spray that was indistinguishable from the active treatment and the other, acupuncture. Additionally, the study involved a no-treatment control. For subjective self-report outcomes, the active treatment, the inert spray and acupuncture were indistinguishable, but all were superior to the no treatment control condition. However, for the objective outcome measure, the active treatment was more effective than all of the three comparison conditions. The message is that credible placebo control conditions are superior to control conditions lacking and positive expectations, including no treatment and, I would argue, ill-defined usual care that lacks positive expectations. A further message is ‘beware of relying on subjective self-report measures to distinguish between active treatments and placebo control conditions’.
At week 6, the change in BFI score from baseline was significantly greater in relaxing acupressure and stimulating acupressure compared with usual care (mean [SD], −2.6 [1.5] for relaxing acupressure, −2.0 [1.5] for stimulating acupressure, and −1.1 [1.6] for usual care; P < .001 for both acupressure arms vs usual care), and there was no significant difference between acupressure arms (P = .29). At week 10, the change in BFI score from baseline was greater in relaxing acupressure and stimulating acupressure compared with usual care (mean [SD], −2.3 [1.4] for relaxing acupressure, −2.0 [1.5] for stimulating acupressure, and −1.0 [1.5] for usual care; P < .001 for both acupressure arms vs usual care), and there was no significant difference between acupressure arms (P > .99) (Figure 2). The mean percentage fatigue reductions at 6 weeks were 34%, 27%, and −1% in relaxing acupressure, stimulating acupressure, and usual care, respectively.
These are entirely expectable results. Nothing new was learned in this study.
The bottom line for this study is that there was absolutely nothing to be gained by comparing an inert placebo condition to another inert placebo condition to an uninformative condition without clear evidence the control condition offered control of nonspecific factors – positive expectations, support, and attention. This was a waste of patient time and effort, as well as government funds, and produced results that were potentially misleading to patients. Namely, results are likely to be misinterpreted the acupressure is an effective, evidence-based treatment for cancer-related fatigue.
How the authors explained their results
Why might both acupressure arms significantly improve fatigue? In our group’s previous work, we had seen that cancer fatigue may arise through multiple distinct mechanisms.15 Similarly, it is also known in the acupuncture literature that true and sham acupuncture can improve symptoms equally, but they appear to work via different mechanisms.40 Therefore, relaxing acupressure and stimulating acupressure could elicit improvements in symptoms through distinct mechanisms, including both specific and nonspecific effects. These results are also consistent with TCM theory for these 2 acupoint formulas, whereby the relaxing acupressure acupoints were selected to treat insomnia by providing more restorative sleep and improving fatigue and the stimulating acupressure acupoints were chosen to improve daytime activity levels by targeting alertness.
How could acupressure lead to improvements in fatigue? The etiology of persistent fatigue in cancer survivors is related to elevations in brain glutamate levels, as well as total creatine levels in the insula.15 Studies in acupuncture research have demonstrated that brain physiology,41 chemistry,42 and function43 can also be altered with acupoint stimulation. We posit that self-administered acupressure may have similar effects.
Among the fallacies of the authors’ explanation is the key assumption that they are dealing with a specific, active treatment effect rather than a nonspecific placebo intervention. Supposed differences between relaxing versus stimulating acupressure arise in trials with a high risk of bias due to unblinded providers of treatment and inadequate control/comparison conditions. ‘There is no there there’ to be explained, to paraphrase a quote attributed to Gertrude Stein
How much did this project cost?
According to the NIH Research Portfolios Online Reporting Tools website, this five-year project involved support by the federal government of $2,265,212 in direct and indirect costs. The NCI program officer for investigator-initiated R01CA151445 is Ann O’Marawho serves ina similar role for a number of integrative medicine projects.
How can expenditure of this money be justified for determining whether so-called stimulating acupressure is better than relaxing acupressure for cancer-related fatigue?
Consider what could otherwise have been done with these monies.
Evidence-based versus science based medicine
Proponents of unproven “integrative cancer treatments” can claim on the basis of the study the acupressure is an evidence-based treatment. Future Cochrane Collaboration Reviews may even cite this study as evidence for this conclusion.
I normally label myself as an evidence-based skeptic. I require evidence for claims of the efficacy of treatments and am skeptical of the quality of the evidence that is typically provided, especially when it comes from enthusiasts of particular treatments. However, in other contexts, I describe myself as a science based medicine skeptic. The stricter criteria for this term is that not only do I require evidence of efficacy for treatments, I require evidence for the plausibility of the science-based claims of mechanism. Acupressure might be defined by some as an evidence-based treatment, but it is certainly not a science-based treatment.
For further discussion of this important distinction, see Why “Science”-Based Instead of “Evidence”-Based?
Broader relevance to psychotherapy research
The efficacy of psychotherapy is often overestimated because of overreliance on RCTs that involve inadequate comparison/control groups. Adequately powered studies of the comparative efficacy of psychotherapy that include active comparison/control groups are infrequent and uniformly provide lower estimates of just how efficacious psychotherapy is. Most psychotherapy research includes subjective patient self-report measures as the primary outcomes, although some RCTs provide independent, blinded interview measures. A dependence on subjective patient self-report measures amplifies the bias associated with inadequate comparison/control groups.
I have raised these issues with respect to mindfulness-based stress reduction (MBSR) for physical health problems and for prevention of relapse in recurrence in patients being tapered from antidepressants .
However, there is a broader relevance to trials of psychotherapy provided to medically ill patients with a comparison/control condition that is inadequate in terms of positive expectations and support, along with a reliance on subjective patient self-report outcomes. The relevance is particularly important to note for conditions in which objective measures are appropriate, but not obtained, or obtained but suppressed in reports of the trial in the literature.