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Summaries and commentaries by editor Adrian White on a selection of recent acupuncture research studies

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Clinical studies

Chronic shoulder pain

▸ Lathia AT, Jung SM, Chen LX. Efficacy of acupuncture as a treatment for chronic shoulder pain. J Altern Complement Med 2009;15:613–8.

This trial (n = 31) compared individualised acupuncture, standardised acupuncture and non-penetrating sham for chronic shoulder pain.

Methods

A single-blind randomised, controlled trial. The participants were adult, outpatient rheumatology clinic patients with shoulder pain for at least 8 weeks, a diagnosis of adhesive capsulitis, osteoarthritis, rotator cuff syndrome or tear, biceps tendonitis or subacromial bursitis. They had to have a total Shoulder Pain and Disability Index (SPADI) score of at least 30 (from a maximum of 100). Thirty-one subjects were randomised to one of three treatment groups: individualised acupuncture points (8–10) according to the Traditional Chinese Medicine (TCM) approach; seven fixed, standard acupuncture points conventionally used for shoulder pain (not described); and sham non-penetrating (Streitberger needle) acupuncture. Subjects received 12 treatments over 6 weeks and were reassessed using the SPADI at the end of the 6 weeks, administered blind. The primary outcome evaluated was the mean change in total SPADI score in each group from baseline to 6 weeks.

Results

After 6 weeks of treatment, the mean total SPADI score improved in all three groups, but the change was clinically significant (ie, at least 10 points) in groups 1 and 2 (−20.3 and −20.4, respectively, versus −6.5 in group 3). The treatment effects of groups 1 and 2 compared to the sham acupuncture group were −13.8 (95% confidence interval (CI): −2.2 to −25.4, p<0.015) and 13.9 (−2.0 to −25.8, p<0.013), respectively. There was no difference between the individualised acupuncture and standardised acupuncture treatments.

Comment

Acupuncture seems to be an effective treatment for these types of chronic shoulder pain. It is remarkable to find a significant difference with such a small sample, particularly as clinical experience suggests that this group is actually difficult to treat.

This study suggests there may be no difference in efficacy between individualised and standardised acupuncture treatment. The use of standard points may make treatment easier for patient care and for further research studies.

Low back pain

▸ Cherkin DC, Sherman KJ, Avins AL, et al. A randomized trial comparing acupuncture, simulated acupuncture, and usual care for chronic low back pain. Arch Intern Med 2009;169:858–66.

This trial (n = 638) compared the effects of traditional acupuncture, standardised acupuncture, non-penetrating sham acupuncture and usual medical care for chronic low back pain.

Methods

A total of 638 adults with chronic mechanical low back pain (3–12 months’ duration) were randomised to individualised acupuncture, standardised acupuncture, simulated acupuncture or usual care. All groups received a self-care book and the usual care group had no additional extra interventions. Patients having all forms of acupuncture were diagnosed at each attendance by a TCM diagnostician. Patients were literally “masked” and had to lie face down on the couch. The individualised acupuncture group had no restrictions on needling and received an average of 10.8 needles. Standardised acupuncture involved treatment with eight needles: BL23, BL40, KI3 bilaterally, and GV3 and “low back ah shi point” unilaterally. In both groups, needles were stimulated to elicit de qi after 10 minutes and just before removal at 20 minutes. Electroacupuncture (EA) was not allowed. Simulated acupuncture involved procedures with a toothpick in a guide tube, to simulate insertion, stimulation and removal, using the same eight points. Ten treatments were provided over 7 weeks by experienced acupuncturists. The primary outcomes were back-related dysfunction (Roland-Morris Disability Questionnaire score; range, 0–23) and symptom bothersomeness (0–10 scale). Outcomes were assessed at baseline and after 8, 26 and 52 weeks.

Figure 1 Back pain response to acupuncture.

Results

At 8 weeks, mean dysfunction scores for the individualised, standardised and simulated acupuncture groups improved by 4.4, 4.5 and 4.4 points respectively, compared with 2.1 points for those receiving usual care (p<0.001). Participants receiving real or simulated acupuncture were more likely than those receiving usual care to experience clinically meaningful improvements on the dysfunction scale (60% vs 39%; p<0.001). Symptoms improved by 1.6 to 1.9 points in the treatment groups compared with 0.7 points in the usual care group (p<0.001). After 1 year, participants in the treatment groups were more likely than those receiving usual care to experience clinically meaningful improvements in dysfunction (59% to 65% vs 50% respectively; p = 0.02) but not in symptoms (p>0.05).

Comment

This study confirms the central findings of a well known German study, viz that both acupuncture and sham acupuncture are superior to usual medical care for treatment of low back pain, and some of that effect remains significant at 1 year. Unlike the German studies, there was no discernible trend for acupuncture to be superior to sham acupuncture. So needle insertion is not important for the effect in these circumstances and the cocktail stick had no different neurophysiological effect than the needle—whether through stimulating peripheral nerves and/or through expectation (etc). Either way, this study suggests that standardised treatment is as good as individualised and probably more efficient in terms of practitioner’s time.

Chronic prostatic pain syndrome

▸ Lee SH, Lee Be. Electroacupuncture relieves pain in men with chronic prostatitis/chronic pelvic pain syndrome: three-arm randomized trial. Urology 2009;73:1036–41.

This study (n = 63) investigated EA for chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS).

Methods

Sixty-three participants were recruited meeting the US National Institutes of Health (NIH) consensus criteria for CP/CPPS. After the inclusion/exclusion criteria were applied, 39 men were randomised to three treatment groups: group 1, advice and exercise plus 12 sessions of EA; group 2, advice and exercise plus 12 sessions of sham EA; and group 3, advice and exercise alone for 6 weeks. A total of six acupuncture points were used to stimulate the sacral nerve and release the piriformis muscle using an electrical pulse generator. Symptoms related to CP/CPPS were assessed using the NIH-Chronic Prostatitis Symptom Index (NIH-CPSI). Prostaglandin E(2) and β-endorphin levels in post-massage urine samples were measured using an enzyme-linked immunosorbent assay.

Results

At 6 weeks, the NIH-CPSI total score had decreased significantly in the EA group compared with the sham EA and advice and exercise groups (p<0.001). On a subscale analysis of the NIH-CPSI, the EA group showed significant decreases in pain-related symptoms compared with the sham EA and advice and exercise groups (p<0.01). All 12 EA participants experienced at least a six-point decrease in the NIH-CPSI total score compared with two of 12 sham EA participants (16.7%) and three of 12 advice and exercise participants (25.0%; p<0.001). The mean prostaglandin E(2) level in the post-massage urine samples had significantly decreased in the EA group (p = 0.023). In contrast, it had increased in the other two groups.

Comment

This study adds to the increasing evidence in favour of acupuncture’s value in treating this indication.

Irritable bowel syndrome

▸ Lembo AJ, Conboy L, Kelley JM, et al. A treatment trial of acupuncture in IBS patients. Am J Gastroenterol 2009;104:1489–97. doi:10.1038/ajg.2009.156

This is the report of the main trial (n = 230) which Ted Kaptchuk and his team from Boston, Massachusetts reported the findings of the earlier study in the well known BMJ paper,1 viz that patients who were treated with sham (non-penetrating) needling together with the full attention of traditional acupuncture (“augmented”) consultation responded better than those who had the same intervention given in an impersonal and standardised manner (“limited” encounter). This leaves questions of whether real acupuncture is superior to sham, whether excluding placebo responders increases the gap between the groups and whether the augmented consultation increases the (specific) effectiveness of acupuncture.

Methods

After the 3 week run in period in which the 230 patients in the intervention groups all had placebo needling, they were seamlessly and unknowingly re-randomised to receive another 3 weeks (6 treatments) of either real or sham acupuncture given by the same total of practitioner—that is, continuing either the limited or augmented encounter.

True acupuncture was given by the process of manualisation, using six fixed points (CV10, ST25, LR3, SP4, PC6, ST37) and any of 11 optional points according to TCM diagnosis. Sham acupuncture involved applying Streitberger needles to predefined non-points. The third arm of the study included a waiting list control group. The primary outcome was the IBS Global Improvement Scale (IBS-GIS) in which patients select one of seven categories to express the change, from substantially worse to substantially improved: a “response” means at least moderately improved. Secondary outcomes included the IBS Symptom Severity Scale (IBS-SSS) on which patients assess five symptoms, maximum score 500; a “response” means an improvement of at least 50. Also used were the IBS Adequate Relief (IBS-AR), and the IBS Quality of Life (IBS-QOL).

Table 1

Patients with Irritable Bowel Syndrome (IBS): % response rates of different groups, as described in text

Results

Although there was no statistically significant difference between acupuncture and sham acupuncture on the IBS-GIS (41 vs 32%, p = 0.25), both groups improved significantly compared with the waiting list control group (37 vs 4%, p = 0.001). Similarly, small differences that were not statistically significant favoured acupuncture over the other three outcomes: IBS-SSS (31 vs 21%, p = 0.18), IBS-AR (59 vs 57%, p = 0.83), and IBS-QOL (17 vs 13%, p = 0.56).

Comment

This study (like in the recent series of large German studies) showed a trend for acupuncture to be better than sham, and both to be superior to waiting list. It could be expected that eliminating those who respond to placebo during the run-in period might increase the gap between acupuncture and sham: but it did not. Moreover, the responses to acupuncture or sham were not modified by whether the consultation was limited or augmented.

Acute migraine

▸ Li Y, Liang F, Yang X, et al. Acupuncture for treating acute attacks of migraine: a randomized controlled trial. Headache 2009;49:805–16

This study (n = 175) from Sichuan in China compared acupuncture with two control groups.

Methods

A total of 218 patients were recruited in seven hospitals in this multi-centre study, when they attended either the neurology or the acupuncture departments with migraine. They had to have not used any medication during the previous 24 hours and to not take any during the study. In all, 175 were included (interestingly, 14 were not included as they were afraid of acupuncture) and were (centrally) randomised into three groups. The specialised acupuncture practitioners involved in giving acupuncture in the study had to receive special training about the methodological requirements of the study. The treatment protocol was devised by consensus of experts. The verum group received acupuncture at TE5, GB34, GB40, TE20 and GB20. Subjects in the other two groups were treated with acupuncture at predefined non-points. Control group 1 received needling close to the verum points but off the meridians; control group 2 were treated at four non-points in arms and legs. Needles were stimulated to elicit de qi in the verum group, but not either of the control groups. Each patient received one session of treatment and was observed over a period of 24 hours. The main outcome measure was the differences in visual analogue scale (VAS) scores before treatment and 0.5, 1, 2 and 4 hours after treatment.

Figure 2 Acute migraine response by treatment group.

Results

Overall, there were only marginal differences between the groups. All groups showed significant decreases in VAS scores by the fourth hour (p<0.05). The largest change was in the acupuncture group, but even there the pain VAS only fell from 5.0 to 4.0. There were small but statistically significant differences between the pain VAS scores for verum and control 2 at 2 hours (p = 0.14) and 4 hours (p = 0.28) after baseline. After 24 hours, complete relief was obtained by 41% the verum acupuncture group, 17% in control 1 and 16% in control 2 (p<0.003)

Comment

This study from China looks impressive in the rigour of its design and conduct. The analysis could be improved, however. The study was based on the idea that acupuncture points are specific: there were only small trends in favour of acupuncture points against nearby non-points, though a few differences from the control group 2 in whom head points were not needled. The data do not really support the authors’ conclusion that “there are specific physiological effects that distinguish genuine acupoints from non-acupoints”.

From the patient’s point of view, on these data acupuncture can hardly be recommended for treatment of acute migraine in comparison to modern, specific anti-migraine medication.

Pilot or uncontrolled studies

Vasomotor rhinitis

▸ Fleckenstein J, Raab C, Gleditsch J, et al. Impact of acupuncture on vasomotor rhinitis: a randomised placebo-controlled pilot study. J Altern Complement Med 2009;15:391–8.

Methods

A total of 24 patients with confirmed diagnosis of vasomotor rhinitis were randomly allocated to either acupuncture or sham laser acupuncture treatment. The sham laser was a deactivated laser pen beaming normal red light. The main outcome measure was the alteration of the nasal sickness score (NSS; score (max) 27 points). Secondary outcome measures were the evaluation of a subjective symptoms score by patients’ diaries and of their quality of life (SF-12 health survey). A credibility assessment regarding the respective treatment was performed.

Results

NSS of patients treated by acupuncture was significantly reduced from 9.3 (SD 3.89) to 4.1 (SD 3.20) points (p<0.001), whereas NSS declined from 5.6 (SD 2.74) to 3.7 (SD 2.61) points after sham treatment (p<0.05). Comparison between the groups revealed a significant change of NSS (Mann-Whitney, p<0.01), an analysis that also considers the significant difference between the baseline values of both groups (p<0.05). Secondary outcome measures did not show significant differences between both groups. The credibility assessment was comparable for both treatments.

Cancer-related fatigue

▸ Balk J, Day R, Rosenzweig M, et al. Pilot, randomized, modified, double-blind, placebo-controlled trial of acupuncture for cancer-related fatigue. J Soc Integr Oncol 2009;7:1–3.

Methods

A modified, double-blind, randomised, placebo-controlled trial was conducted. The subject, clinical staff, and assessor were blinded, but the acupuncturist was not. Subjects received acupuncture once to twice per week during the 6 week course of radiation therapy. Data were collected at baseline, 3 weeks, 6 weeks, and 10 weeks, which was 4 weeks after that last radiation session. Twenty-seven subjects enrolled and 23 completed the last data collection.

Results

Both true and sham acupuncture groups had improved fatigue, fatigue distress, quality of life and depression from baseline to 10 weeks. The true acupuncture group improved 5.50 (SE 1.48) points on the Functional Assessment of Chronic Illness Therapy-Fatigue Subscale (FACIT-F), whereas the sham acupuncture group improved by 3.73 (SE 1.92) points. This difference was not statistically significant (p = 0.37). All subjects guessed that they were in the true acupuncture group. Our study was underpowered to find a statistically significant difference, which would require 75 subjects per group. Owing to poor recruitment, the feasibility of a larger trial using the same methodology is low.

Xerostomia (radiation induced)

▸ Garcia MK, Chiang JS, Cohen L, . Acupuncture for radiation-induced xerostomia in patients with cancer: a pilot study. Head Neck 2009 Apr 17 Epub.

In this case series, 19 patients received acupuncture twice a week for 4 weeks. The xerostomia inventory (XI) and patient benefit questionnaire (PBQ) scores were significantly better after acupuncture on weeks 4 and 8 than at baseline (XI: p = 0.0004 and 0.0001; PBQ: p = 0.0004 and 0.0011, respectively). For QOL at weeks 4 and 8, there was a significant difference for questions related to head/neck cancer (p = 0.04 and 0.006, respectively). At week 8, there was a significant difference in physical wellbeing (p = 0.04). At weeks 5 and 8, there were significant differences in the total score (p = 0.04 and 0.03, respectively).

Systematic reviews

Postoperative nausea and vomiting

▸ Lee A, Fan LT. Stimulation of the wrist acupuncture point P6 for preventing postoperative nausea and vomiting. Cochrane Database Syst Rev 2009;(2):CD003281.

This is an update of a Cochrane review first published in 2004.

Methods

The authors included all randomised trials of any techniques of stimulating the PC6 acupoint compared with sham treatment or drug therapy for the prevention of postoperative nausea and vomiting. Interventions included acupuncture, electroacupuncture, transcutaneous nerve stimulation, laser stimulation, capsicum plaster, an acu-stimulation device and acupressure in patients undergoing surgery. Primary outcomes were the risks of nausea and vomiting. Secondary outcomes were the need for rescue antiemetic therapy and adverse effects.

Results

Forty trials involving 4858 participants were included. Compared with sham treatment PC6 acupoint stimulation significantly reduced: nausea (RR 0.71, 95% CI 0.61 to 0.83); vomiting (RR 0.70, 95% CI 0.59 to 0.83) and the need for rescue antiemetics (RR 0.69, 95% CI 0.57 to 0.83). Heterogeneity among trials was moderate. There was no clear difference in the effectiveness of PC6 acupoint stimulation for adults and children; or for invasive and non-invasive acupoint stimulation. The results for acupuncture are shown in the fig 3. There was no evidence of difference between P6 acupoint stimulation and antiemetic drugs in the risk of nausea (RR 0.82, 95% CI 0.60 to 1.13), vomiting (RR 1.01, 95% CI 0.77 to 1.31), or the need for rescue antiemetics (RR 0.82, 95% CI 0.59 to 1.13). The side effects associated with PC6 acupoint stimulation were minor. There was no evidence of publication bias from contour-enhanced funnel plots.

Figure 3 Meta-analysis of acupuncture for nausea.

Authors’ conclusions

PC6 acupoint stimulation prevented postoperative nausea and vomiting. There was no reliable evidence for differences in risks of postoperative nausea or vomiting after P6 acupoint stimulation compared to antiemetic drugs.

Meniere’s syndrome

▸ Long AF, Xing M, Morgan K, et al. Exploring the evidence base for acupuncture in the treatment of Meniere’s syndrome—a systematic review. Evid Based Complement Alternat Med 2009 Jun 8 Epub.

A systematic review of English and Chinese literature, including randomised, non-randomised and observational studies. Twenty-seven studies were included in this review (nine in English and 18 in Chinese languages): three randomised controlled trials, three non-randomised controlled studies and four pre-test, post-test designs. All but one of the studies were conducted in China. The studies covered body acupuncture, ear acupuncture, scalp acupuncture, fluid acupuncture point injection and moxibustion. The studies were of varying quality. The weight of evidence, across all study types, is of beneficial effect from acupuncture, for those in an acute phase or those who have had Ménière’s syndrome for a number of years. The review reinforces the importance of searching for studies from English and Chinese literature.

Allergic rhinitis

Lee MS, Pittler MH, Shin BC, . Acupuncture for allergic rhinitis: a systematic review. Ann Allergy Asthma Immunol 2009;102:269–79.

This systematic review located seven trials of high quality which met standards of methodological rigour. All RCTs tested the effectiveness of acupuncture on allergic rhinitis symptoms. Three RCTs failed to show superiority of acupuncture for treating or preventing symptoms for seasonal allergic rhinitis compared with placebo acupuncture. For perennial allergic rhinitis, one study reported favourable effects of acupuncture on a rhinitis symptoms score and one found positive results for a nasal symptoms score compared with placebo acupuncture (n = 152; standard mean difference, 0.45; 95% CI, 0.13 to 0.78; p = 0.006; heterogeneity: χ2 = 0.45, p = 0.50, I2 = 0%). Two RCTs compared acupuncture with oral pharmacologic medications. Their results were in favour of acupuncture.

The evidence for the effectiveness of acupuncture for the symptomatic treatment or prevention of allergic rhinitis is mixed. The results for seasonal allergic rhinitis failed to show specific effects of acupuncture. For perennial allergic rhinitis, results provide suggestive evidence of the effectiveness of acupuncture.

Safety of acupuncture

▸ Witt CM, Pach D, Brinkhaus B, et al. Safety of acupuncture: results of a prospective observational study with 229,230 patients and introduction of a medical information and consent form. Forsch Komplementmed 2009;16:91–7

To evaluate the safety of acupuncture in a large number of patients receiving conventional healthcare and, based on these results, to develop a new medical consent form for acupuncture.

Methods

The prospective observational study included patients who received acupuncture treatment for chronic osteoarthritis pain of the knee or hip, low back pain, neck pain or headache, allergic rhinitis, asthma, or dysmenorrhoea. After treatment, all patients documented adverse events associated with acupuncture (defined as adverse effects). Patients who reported a need for treatment due to an adverse effect completed an additional standardised questionnaire on the most important adverse effect. Based on this data and considering ethical and legal aspects a new consent form was developed.

Results

A total of 229 230 patients received on average 10.2 (SD 3.0) acupuncture treatments. Altogether, 19 726 patients (8.6%) reported experiencing at least one adverse effect and 4963 (2.2%) reported one which required treatment. Common adverse effects were bleeding or haematoma (6.1% of patients, 58% of all adverse effects), pain (1.7%) and vegetative symptoms (0.7%). Two patients experienced a pneumothorax (one needed hospital treatment, the other observation only). The longest duration of a side effect was 180 days (nerve lesion of the lower limb). The resulting medical consent form consists of five modules: Introduction to acupuncture and moxibustion, Risks of acupuncture treatment, Conditions which can increase the risk, Doctor’s statement and Consent.

In conclusion, acupuncture provided by physicians is a relatively safe treatment and the proposed consent form could support both patients and professionals in the process of obtaining informed consent.

Basic science

Skin resistance at “acupuncture points”

▸ Kramer S, Winterhalter K, Schober G, et al. Characteristics of electrical skin resistance at acupuncture points in healthy humans. J Altern Complement Med 2009;15:495–500.

Some practitioners use electrical skin resistance (ESR) to indicate “acupuncture points” objectively, though there is little supportive evidence. This single-blinded study from the University of Munich measured the ESR at six common acupuncture points (TE5, PC6, LU6, ST36, SP6, GB39) in 53 subjects. Measurements were repeated in subgroups at varying time intervals (1 minute, 1 hour, 1 week).

The researchers used a special array of 64 (8×8) electrodes to measure the ESR over an area of 6×6 cm. Then they located the electrodes corresponding to the acupuncture point and compared the ESR with the surrounding electrodes. This method made it possible to minimise major influence factors on electrical skin impedance measurements.

They made 631 measurements. In 62.8% of the measurements of acupuncture points, no significant ESR difference was found. In 234 (37.2%) of the measurements, the ESR at the AP was significantly different from the surrounding skin area, with 163 (25.9%) points showing a lower and 71 (11.3%) points showing a higher ESR. Reproducibility was high after 1 minute but was low after 1 hour and 1 week.

These results indicate that acupuncture points do not show any changes in ESR that are consistent in direction or stable over time. Thus, ESR does not provide any basis for point localisation, or for diagnostic or therapeutic purposes.

Increased muscle blood flow with acupuncture

▸ Ohkubo M, Hamaoka T, Niwayama M, et al. Local increase in trapezius muscle oxygenation during and after acupuncture. Dyn Med 2009:16;8:2.

This study aimed to test the hypothesis that acupuncture stimulation provokes a localised increase in muscle blood volume and oxygenation in the stimulation region.

Methods

Two sets of near-infrared spectrometer (NIRS) probes were placed on the trapezius muscle. There was a 40 mm space between the light-source and the detector in each set, and a 50 mm distance between the two sets of probes. An acupuncture needle was inserted into the muscle under one of the sets (in between source and detector); the other set acted as the distant control. Measurements of muscle oxygenation (oxy-Hb) and blood volume (t-Hb) changes close to the needle and 50 mm distant were measured in nine acupuncture-experienced subjects. Ten healthy volunteers acted as the control group (no acupuncture). Measurements began with a 3 min rest period, followed by acupuncture stimulation for 2 min and then recovery after stimulation.

Results

There was a significant increase in oxy-Hb (60.7 muM at maximum) and t-Hb (48.1 muM at maximum) in the stimulation region as compared to the distant region. In significant increases in oxy-Hb and t-Hb were first noted at 58.5 s and 13.5 s, respectively, after the onset of stimulation.

Conclusion

Oxygenation increases after about a minute and blood volume increases after about 15 seconds in the muscle around an acupuncture needle; the increases cannot be detected at a distance of 3 cm.

Acupuncture research methodology

▸ Miyazaki S, Hagihara A, Kanda R, et al. Applicability of press needles to a double-blind trial: a randomised, double-blind, placebo-controlled trial. Clin J Pain 2009;25:438–44.

Owing to a lack of a suitable needle procedure, it has been impossible to evaluate the efficacy of acupuncture in clinical studies using double-blind testing. We evaluated the applicability of a new kind of press needle (Pyonex) to a double-blind trial by comparing the press needle with a placebo (lacking the needle element).

Methods

The purpose of the study consisted of two phases. In phase 1, to evaluate the applicability and efficacy of the press needles, 90 participants who had never been treated using acupuncture were randomly assigned to receive either the press needle (n = 45) or a placebo (n = 45). The applicability was measured using a questionnaire regarding the perception of penetration, and efficacy was measured using a VAS of low back pain (LBP). When the applicability and efficacy of the press needles were confirmed in phase 1, the mechanism of LBP relief by the press needles was examined in phase 2.

Results

In phase 1, intergroup comparisons showed no significant differences concerning the perception of penetration. In addition, for patients with LBP, the press needles reduced the subjective evaluation of LBP compared with the placebo (p<0.05). In phase 2, VAS results indicated that LBP was reduced significantly more in the press needle group than in the local anaesthesia group (p<0.05).

These findings imply that the press needle and a placebo provide an effective means of realizing a double-blind setting for clinical studies of acupuncture.

REFERENCES

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Footnotes

  • Provenance and peer review Not commissioned; not externally peer reviewed.

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