Can acupuncture treatment be double-blinded? An evaluation of double-blind acupuncture treatment of postoperative pain.
Blinding protects against bias but the success of blinding is seldom assessed and reported in clinical trials including studies of acupuncture where blinding represents a major challenge. Recently, needles with the potential for double-blinding were developed, so we tested if acupuncture can be double-blinded in a randomized study of sixty-seven patients with acute pain ≥ 3 (0-10 scale following third molar removal) who received active acupuncture with a penetrating needle or placebo acupuncture with a non-penetrating needle. To test if acupuncture was administered double-blind, patients and acupuncturists were asked about perceived treatment allocation at the end of the study. To test if there were clues which led to identification of the treatment, deep dull pain associated with needle application and rotation (termed "de qi" in East Asian medicine), and patients' pain levels were assessed. Perceived treatment allocation depended on actual group allocation (p < 0.015) for both patients and acupuncturists, indicating that the needles were not successful in double-blinding. Up to 68% of patients and 83% of acupuncturists correctly identified the treatment, but for patients the distribution was not far from 50/50. Also, there was a significant interaction between actual or perceived treatment and the experience of de qi (p = 0.027), suggesting that the experience of de qi and possible non-verbal clues contributed to correct identification of the treatment. Yet, of the patients who perceived the treatment as active or placebo, 50% and 23%, respectively, reported de qi. Patients' acute pain levels did not influence the perceived treatment. In conclusion, acupuncture treatment was not fully double-blinded which is similar to observations in pharmacological studies. Still, the non-penetrating needle is the only needle that allows some degree of practitioner blinding. The study raises questions about alternatives to double-blind randomized clinical trials in the assessment of acupuncture treatment.
Department of Psychology and Behavioural Sciences, Aarhus University, Aarhus, Denmark; Danish Pain Research Center, Aarhus University Hospital, Aarhus, Denmark.
Lene
L
Vase
Section of Clinical Oral Physiology, Department of Dentistry, Aarhus University, Aarhus, Denmark; Section of Oral and Maxillofacial Surgery and Oral Pathology, Department of Dentistry, Aarhus University, Aarhus, Denmark.
Sara
S
Baram
Department of Acupuncture and Moxibustion, Tokyo Ariake University of Medical and Health Sciences, Tokyo, Japan.
Nobuari
N
Takakura
Department of Acupuncture and Moxibustion, Tokyo Ariake University of Medical and Health Sciences, Tokyo, Japan.
Miho
M
Takayama
Department of Acupuncture and Moxibustion, Tokyo Ariake University of Medical and Health Sciences, Tokyo, Japan.
Hiroyoshi
H
Yajima
Department of Acupuncture and Moxibustion, Tokyo Ariake University of Medical and Health Sciences, Tokyo, Japan.
Akiko
A
Kawase
The Acupuncture Academy, Copenhagen and Aarhus, Denmark.
Lars
L
Schuster
Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, United States of America.
Ted J
TJ
Kaptchuk
Section of Clinical Oral Physiology, Department of Dentistry, Aarhus University, Aarhus, Denmark.
Søren
S
Schou
Danish Pain Research Center, Aarhus University Hospital, Aarhus, Denmark.
Troels Staehelin
TS
Jensen
Department of Psychology and Behavioural Sciences, Aarhus University, Aarhus, Denmark; Department of Oncology, Aarhus University Hospital, Aarhus, Denmark.
Robert
R
Zachariae
Section of Clinical Oral Physiology, Department of Dentistry, Aarhus University, Aarhus, Denmark.
Peter
P
Svensson
D015667:Acupuncture Analgesia / Q000295:instrumentation* / Q000379:methods*; D000328:Adult; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D059408:Pain Management / Q000295:instrumentation* / Q000379:methods*; D010149:Postoperative Pain / Q000628:therapy*; D014081:Tooth Extraction / Q000009:adverse effects