ABSTRACT
CONTEXT: It's difficult to conduct experiments using a double-blind design in controlled clinical trials of acupuncture. To resolve this problem with blinding, we designed double-blind needles (DBNs) with stuffing to mimic the resistance felt during insertion of a regular acupuncture needle. Results of the past studies using 0.16 mm diameter DBNs found that the resistance felt by the acupuncturists during insertion successfully blinded them. OBJECTIVE: The study intended to compare the effects on an acupuncturist's blinding when the practitioner used penetrating DBNs with 0.14, 0.16, 0.18, and 0.20 mm diameters. DESIGN: We conducted a double-blind randomized trial. SETTING: The study took place at the Japan School of Acupuncture, Moxibustion. and Physiotherapy in Tokyo, Japan. PARTICIPANTS: The participant was one licensed acupuncturist who performed 320 needle insertions during acupuncture for 20 healthy students, who were familiar with acupuncture and who attended the Japan School of Acupuncture, Moxibustion, and Physiotherapy. METHODS: The acupuncturist was informed she would administer a penetrating or non-penetrating needle; however, only penetrating needles were used. She inserted the four sizes of needles in both of each student's dorsal forearms using an alternating twirling technique. This procedure was repeated once more on another day, with at least one day between sessions. PRIMARY OUTCOME MEASURES: After the acupuncturist removed each needle, we asked her to guess: (1) the type of needle inserted, (2) her level of confidence in the guess, and (3) the clues that contributed to her guess. A chi-squared test was used to determine whether the ratio of correctly or incorrectly identified needles met an expected probability of 0.5 for each needle diameter. RESULTS: Of the 320 needle insertions, the acupuncturist correctly identified 54% of 0.14 mm, 45% of 0.16 mm, 46% of 0.18 mm, and 50% of 0.20 mm needle insertions. The correct and incorrect ratios of identified needles were fitted with a probability of 0.5, with no significant differences in the acupuncturist's confidence (P = .16). In 99% of the tests, the cue that contributed to the acupuncturist's guess was the feeling of the needle insertion. CONCLUSION: These findings indicate that the differences in the diameters of DBNs from 0.14 to 0.20 mm didn't significantly affect the acupuncturist's blinding.
Subject(s)
Acupuncture Therapy , Needles , Double-Blind Method , Female , HumansABSTRACT
To investigate the acupuncture sensations elicited by the Japanese style of acupuncture, penetrating acupuncture and skin-touch placebo needles were randomly administered at various insertion depths (5 and 10 mm for the penetrating needles and 1 and 2 mm for the placebo needles) at LI4 to 50 healthy subjects. Among the 12 acupuncture sensations in the Massachusetts General Hospital Acupuncture Sensation Scale (MASS), "heaviness" was the strongest and most frequently reported sensation with the 10 mm needles, but not with the 5 mm needles. There were no significant differences in number of sensations elicited, MASS index, range of spreading, and intensity of needle pain for 5 mm penetration versus 1 mm skin press and 10 mm penetration versus 2 mm skin press. The MASS index with 2 mm skin-touch needles was significantly larger than that with 1 mm skin-touch and 5 mm penetrating needles. The factor structures in the 12 acupuncture sensations between penetrating and skin-touch needles were different. The acupuncture sensations obtained in this study under satisfactorily performed double-blind (practitioner-patient) conditions suggest that a slight difference in insertion depth and skin press causes significant differences in quantity and quality of acupuncture sensations.
ABSTRACT
OBJECTIVE: To investigate the influence of the depth of skin press in blunt tip placebo acupuncture needles on patient blinding and its relationship to needle diameter. METHODS: Forty healthy volunteers were enrolled as subjects for patient blinding. Four acupuncturists applied the following needles randomly at three points in each forearm: 0.18â¯mm and 0.25â¯mm diameter penetrating needles inserted to a depth of 5â¯mm, and 0.18â¯mm and 0.25â¯mm diameter skin-touch needles depressing the skin at the acupoint to a depth of 1â¯mm and 2â¯mm from the skin surface. The subjects reported their guesses at the nature of needles they received, and rated needle pain and de qi. A blinding index was calculated to define the success of blinding for subjects. RESULTS: The blinding status of subjects for 1â¯mm press needles of 0.18â¯mm diameter was "random guess", but "unblinded" for 1â¯mm press needles of 0.25â¯mm diameter. For 2â¯mm press needles of both diameters, the blinding status was "opposite guess" and the blinding status for penetrating needles of both diameters was "unblinded." The percentages of "felt pain" with 2â¯mm press needles of both diameters were similar to that with penetrating needles, but those were not similar for 1â¯mm press needles. The frequency of de qi occurrence with 2â¯mm press needles of 0.18â¯mm diameter was similar to that of penetrating needles of both diameters. CONCLUSION: Placebo needles of 2â¯mm press made more subjects guess that the needles penetrated the skin than 1â¯mm press needles. The use of small diameter needles increased patient blinding.
Subject(s)
Acupuncture Therapy/instrumentation , Needles/statistics & numerical data , Acupuncture Points , Acupuncture Therapy/methods , Adult , Female , Healthy Volunteers , Humans , Male , Middle Aged , Placebo Effect , Sensation , Young AdultABSTRACT
Acupuncture sensations are considered essential in producing the treatment effect of acupuncture. The Massachusetts General Hospital Acupuncture Sensation Scale (MASS) is a frequently used scale in acupuncture research to measure acupuncture sensations. We translated the MASS into Japanese (Japanese MASS) based on Beaton's guidelines. 30 acupuncturists evaluated the relevancy and meaning of the 12 descriptors included in the Japanese MASS. The content validity ratios for 10 of the 12 descriptors were 0.33 or greater. 42 healthy subjects then evaluated acupuncture sensations evoked by manual acupuncture at LI4 using the Japanese MASS. Cronbach's alpha was 0.86. The correlation coefficient of total MASS scores and total Short Form McGill Pain Questionnaire scores and MASS indices and sensory visual analogue scores were 0.78 and 0.80, respectively. Factor analysis loaded the 12 descriptors onto two meaningful factors. This study demonstrated that the Japanese MASS has good reliability, content validity, criterion-related validity, and construct validity. Therefore, the Japanese MASS is a valid and reliable instrument for use with Japanese populations.