A single-blind, randomized, placebo-controlled clinical trial was conducted at the University of Medical Sciences in Iran during 2008. The protocol received institutional review board approval. Permission to conduct the study and access to the female students were obtained from the director of the Medical University. The Medical Research Ethics Committee of Shiraz University of Medical Sciences approved the study prior to commencement, and permission was obtained from the Dean of Faculty, the Deputy of Educational Affairs, and the Educational Affairs Administration of University of Medical Sciences to conduct the study in the setting.
A total of 86 full-time female students studying at the University of Medical Sciences participated in the study. An informed consent form was signed by each participant before entering the study and the confidentiality and anonymity of the study were guaranteed.
The inclusive criteria were (1) having regular menstrual cycles (3–8 days of menstruation with intervals of 22–35 days); (2) not taking any medication such as hormonal contraceptives, antipsychotics, antidepressants, vitamins; (3) not suffering from any psychiatric disorder, such as major depressive disorder, panic disorder, or epilepsy; and (4) being a resident at the university's dormitory.
Exclusion criteria were (1) acquiring General Health Questionnaire (GHQ) scores more than 23; (2) suffering from any kind of psychiatric disorders; (3) consumption of any kind of antidepressants, tranquilizers, and psychiatric medicine; (4) students studying physiotherapy. Individuals who did not meet inclusion criteria were excluded from the study at this stage.
From power calculation, a total of 43 participants in each treatment group, with 31 completing the study, were needed for 80% power to detect a 55% difference in general health scores at the statistical significance level of less than 0.05.
Participants were studied for 2 months. Before commencement of the study, the data on demographics were gathered. A GHQ17
was also used to assess the psychologic status of participants prior to the intervention. It has been shown that the general population has been extensively screened for psychiatric problems by means of the short version of GHQ-28.18,19
The GHQ-28 contains 28 items. It has four subscales evaluating somatic symptoms, anxiety, social dysfunction, and depression. Every item has a 4-point scoring system, ranging from a “better/healthier than normal,” “same as usual,” “worse/more than usual” to a “much worse/more than usual.” Previous studies have confirmed the reliability and validity of the questionnaire.18,19
In the current research study, the Likert scoring method (scoring rages: 0-1-2-3) was used. The cutoff point for GHQ-28 scoring was considered to be 23. Higher scores demonstrated a more severe problem.
Distributed questionnaires were collected after the first menstrual cycle. The participants gaining scores higher than 23 were not considered for the study intervention, and were referred to a psychologist for further assessment and possible treatment. Data from those who had the scores of 23 or less were included in the study. Among them, 86 were randomly allocated to one of the 2 groups as follows: A number was assigned to each questionnaire.
Then, two questionnaires were selected randomly and were placed upside down, so that they could not have been recognized. Then, the researcher allocated one of them to the study group and another one to the control group. Therefore, the first person in each of two study groups was identified. After that, the 84 remaining participants were divided into 42 groups. Each group consisted of 2 persons each. The participants of each pair were then randomly allocated to one of the two groups. This resulted finally in two groups of 43 persons each.
In order to specify the accurate point of SP6 on the participant's leg in the acupressure group (study group), the researcher placed a portable battery-powered point-scope Unit on the lower area of the leg, 5
cm above the medial malleous (SEVESA model, Germany). A red lamp was lit, when the acupressure point, SP6, was right under the Unit.
In order to be able to conduct acupressure on the SP6 point, 1 researcher was trained by an expert clinician.
Acupressure at Sanyinjiao
point (above the ankles) was then performed during menstrual bleeding of each participant in the acupressure group. The sham point,20
however, was pressed in participants in the control group (n
=43). Navidi et al. indicated: “The sham point was chosen on the dorsal side of the leg, away from meridians and is not situated upon the Achilles tendon. According to the acupressure and acupuncture specialists' recommendation and with regard to the text books, this point is not located on a meridian and pressing it is unlikely to cause any changes in the general health of people.”21,22
One (1) month before commencement of the study, the researcher was trained by an expert. A scale (20
kg) was used to measure the force of finger pressure. The force of finger pressures was measured 30 times every day, and the pressures concerning 1.21
kg and 3.53
kg were practiced by the researcher.
Participants were positioned prone on an intervention table, having a pillow under their head, shoulders, and knees, on the first day of their menstrual bleeding. Acupressure at the Sanyinjiao
(SP6) acupoint was performed alternately on each leg of participants of the study group. The initial force of pressure was 1.21
kg per single pressure action, gradually increasing to 3.53
kg at the end of the pressure round for each leg. The researcher used her thumb to press SP6 for 6 seconds and then released the pressure for 2 seconds, and this cycle was repeated for 30 minutes. In the control group, the sham point was pressed in the same manner. This procedure was repeated for the next consecutive menstrual cycle within each group.
The GHQs were completed by participants immediately after each intervention cycle. In addition, individuals were asked to record any adverse events. After two cycles, questionnaires were collected and data were analyzed. Data analysis was carried out using SPSS version 13.5 for Windows. The independent t test was used to compare the mean scores of general health before and after intervention in each group (α=0.05, confidence interval=95%). In addition, analysis of variance was applied to compare differences in mean scores of general health between groups. Tukey's post-hoc for pair comparison was also performed. Demographic data and study side-effects were summarized by means of descriptive statistics. A p-value less than 0.05 was considered statistically significant.