The diagnosis of chronic insomnia was made with clinical interviews according to the American Academy of Sleep Medicine International Classification of Sleep Disorders, Third Edition (ICSD-3). The inclusion criteria were as follows: (1) 18 to 75 years old. (2) In compliance with the diagnostic criteria for chronic insomnia in ICSD-3. (3) In compliance with the TCM diagnostic criteria for insomnia, TCM syndrome of dysregulated coordination between the heart and the kidney. (4) Consistent administration of sedative-hypnotic drugs for more than 3 months before entering the study or not taking such drugs. (5) A total score higher than five on the Pittsburgh Sleep Quality Index (PSQI) questionnaire. (6) Patients voluntarily participated in the study and signed informed consent forms.
All subjects who wanted to participate were given an outpatient interview to determine whether they met the inclusion criteria. The interviews were conducted by experienced clinicians in the form of semistructured interview questionnaires. The interview questionnaire included the cause of insomnia, the onset process, the main sleep complaints at the current time, the treatment process, the state before going to bed, the sleep-wake cycle, other sleep-related symptoms, mental states, and daytime symptoms. Individuals on stable doses of sedative-hypnotic medications were allowed to remain on them during the study. In addition, all subjects completed a one-week sleep diary to establish sleep patterns before the clinical interview.
The exclusion criteria were as follows: (1) severe hepatic or renal function damage, haematological disease, respiratory disease, or diagnosis of one or more mental disorders according to the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). (2) semistructured interviews determined that subjects had sleep disorders other than chronic insomnia. (3) Infectious diseases such as infectious hepatitis, tuberculosis, AIDS and syphilis. (4) Severe digestive system diseases or severe malnutrition. (5) Pregnant or lactating. (6) Severe trauma with no cure or other contraindications to acupuncture, such as allergic constitution or severe dermatosis. (7) An Apnoea-Hypopnea Index >10 or periodic limb movements index during sleep associated with >15 arousals per hour on diagnostic PSG. (8) Participation in other clinical trials in the last 3 months.
The acupuncturist had received a master's degree in acupuncture and tui na, had a doctor qualification certificate, and had more than 3 years of acupuncture clinical work experience. All the research assistants received 3 days of training before the start of the study.
Subjects in the acupuncture group were placed in a supine position. The acupuncturist selected two acupoints, HT 7 and KI 7. These acupoints were selected based on a previous systematic review and our clinical experience summary and because the use of only two points can streamline the treatment and alleviate patient pain. The needles used were disposable, sterile, stainless-steel acupuncture needles with a length of 40 mm and a diameter of 0.25 mm (Andy, Guizhou, China). The acupuncturist treated each acupoint bilaterally, and the depth of insertion was 10-20 mm. The acupuncturist selected the depth according to the subject's body type (high, short, fat and thin). After penetration, the acupuncturist lifted and twisted the needles to induce the subject's sensation of "De qi", and the needle was left for 20 minutes. "De qi" refers to manipulation of the needle by the acupuncturist (extract, intercalate, twist, and rotate) after the needle has been inserted into the acupoints to a certain depth so that the acupoints can be induced by the meridians. The patient has a conscious response, such as soreness, numbness, or tenderness. According to TCM, this is the key to the curative effect of acupuncture.
In our study, different types of acupuncture treatments will be compared. One is ordinary acupuncture, and the other is related to the positive results in previous clinical studies.
Subjects in the sham acupuncture group were treated with shallow needling of sham acupoints. Due to its convenience, this control group setting method has been widely used in acupuncture clinical research, especially for the purpose of exploring acupoint-specific effects among the Chinese population. Sham HT 7 was 2 cun ( 40 mm) lateral to HT 7, and sham KI 7 was 2 cun ( 40 mm) lateral to KI 7 (Figure 1). The purpose of choosing the sham points in this way is explained in previous similar clinical studies; this approach avoids the true acupoints and meridian routes. Choosing sham points close to the true acupoints was conducive to blinding. The acupuncturist took the sham points on both sides and performed needling at a depth of 2-4 mm, sufficient only to penetrate the skin. The acupuncturist did not manipulate the needles and did not cause "De qi". The parameters of the acupuncture needles were identical to those used in the acupuncture group. Subjects in the two groups received the same treatment, which included 3 times a week for a total of 10 treatments. Each subject experienced screening, treatment, and a follow-up period of approximately 8 weeks, and the treatment phase lasted approximately 3.5 weeks. All subjects were treated equally to prevent them from perceiving differences. They were told about the methods of acupuncture as follows: 
Pittsburgh Sleep Quality Index (PSQI): The PSQI contains 19 self-assessed items and 5 other-rated items. The self-assessed items evaluate duration of sleep, sleep onset latency, sleep efficiency, sleep disturbance, need for medications to sleep, daytime dysfunction, and overall sleep quality. The total score is 0-21. A higher score indicates a worse quality of sleep. The PSQI is widely used to evaluate sleep dysfunction, and it is more inclined to evaluate the subject's sleep state during the workday. A total score >5 indicates that the subjects have poor sleep quality and has significance for clinical treatment. The Chinese version of the PSQI has high reliability and validity for the Chinese population and has been used as an effective tool for sleep screening in clinical and scientific research. This study evaluated the PSQI at baseline, posttreatment, one-week follow-up and one-month follow-up.
Insomnia Severity Scale (ISI): The ISI mainly evaluates the nature and severity of insomnia and its impact on daytime function. The scale consists of 7 evaluation items, and the total score ranges from 0-28 points. A higher score indicates more severe insomnia. The ISI is mainly used to screen for insomnia and to evaluate treatment effects in clinical research. A total score of 8-14 indicates subclinical insomnia, and a total score >14 indicates clinically significant insomnia. A reduction in the ISI score by 8 points or more reflects a significant treatment effect in clinical evaluations. ISI has good reliability and validity. The Chinese version has high reliability and validity for evaluating insomnia among the Chinese population. This study evaluated ISI at baseline, posttreatment, one-week follow-up and one-month follow-up.
Polysomnography (PSG): PSG was used as the objective sleep evaluation index. The PSG (NIHON KOHDEN, Japan) used in this study was composed of multiple quantitative parameters. The collection indicators included electroencephalogram (EEG), mentalis electromyography (EMG), bilateral electrooculography (ECoG), oral/nasal airflow, and bilateral anterior tibial EMG. In this study, PSG was used for two consecutive nights to eliminate the "first night effect". PSG monitoring started from the usual bedtime to the next morning, and a total of 8.0 hours were recorded. The efficacy evaluation of this study was based on EEG. The sleep stages and parameters were manually scored based on the American Academy of Sleep Medicine Manual for the Scoring of Sleep and Associated Events. The objective sleep evaluation parameters used in this study included the following: total sleep duration (TST); sleep onset latency (lights out to first epoch of any sleep, SOL); REM sleep latency (REM-sl); wake after sleep onset (WASO, SOL minus TST); sleep efficiency (SE, TST/total recording time x 100%); arousal index (Arl; number of arousals x60/TST); and percent time in each stage (length of each sleep stage/TSTx100%). In this study, during the screening period and at posttreatment, two consecutive monitorings were performed, but only the second result for each timepoint was used as the efficacy evaluation index.
Beck Anxiety Inventory (BAI): The BAI was developed by Beck et al in 1988 and contains a total of 21 anxiety symptom items. It has been used as an evaluation index to evaluate the anxiety state of the subject within the past week. Higher scores correspond to more serious anxiety. Generally, BAI>=45 is used as the criterion to indicate anxiety. The scale is simple in content, easy to administer, and easily understood. The Chinese version has good reliability and validity and is commonly used for the evaluation of anxiety symptoms in China. This study evaluated it at baseline and posttreatment.
Beck Depression Inventory (BDI): The BDI was developed by Beck et al according to the diagnostic criteria for depression in the DSM-IV. Beck et al formulated the first version of the BDI in 1961 and restructured it for the second version, which is now generally used. The BDI has a total of 21 self-evaluated depression-related items that can evaluate depression in the past 7 days. The higher the total score, the more severe the depression. A total score of 0-13 indicates no depression, 14-19 indicates mild depression, and 29-63 indicates severe depression. The Chinese version of the BDI has good validity and reliability. This study evaluated it at baseline and posttreatment.
Fatigue Severity Scale (FSS): FSS was proposed and formulated by Krupp et al in 1989. The FSS scale is simple and clear. It consists of only 9 self-evaluation items. Subjects scored themselves on the corresponding symptoms. Higher total scores indicate more fatigue. Studies have shown that the FSS score of patients with insomnia is higher than 5.5, which means that there is a high level of daytime fatigue among patients with insomnia. The Chinese version of the FSS has good validity and reliability. This study evaluated the FSS at baseline and posttreatment.
Epworth Sleepiness Scale (ESS): The ESS is a relatively simple and internationally recognized sleepiness assessment scale. It has a total score of 24 points. The higher the score is, the more severe the daytime sleepiness. This scale is generally used to screen and evaluate the hypopnea status of patients with obstructive sleep apnoea-hypopnea syndrome (OSAHS), but studies have shown that the ESS scale can be used to screen and diagnose other sleep disorders. The Chinese version of the ESS has good validity and reliability. This study used the ESS to assess the daytime sleepiness of subjects at baseline and posttreatment.
Two types of safety assessments were performed: evaluation of changes in routine blood tests, liver function, and kidney function after the 10 intervention sessions and records of adverse events during the entire study. The record of adverse events in this study was conducted using the Adverse Event Record Form. Subjects were required to fill in the list of adverse events during the study, including the time point, severity, measures taken, whether the event was related to the treatment and prognosis. During the assessment phase, researchers assessed the possible relationship between adverse events and the study treatment, as well as medications taken concurrently. Adverse events include all adverse reactions that are definitely related to treatment, most likely related to treatment, and likely related to treatment.
The required sample size was estimated based on the change in PSQI scores. According to previous research by our team, sham acupuncture can reduce the PSQI to 14.76 after 10 interventions, with an SD of 3.35. This study hypothesized that acupuncture at HT 7 and KI 7 for insomnia would reduce the PSQI by 2.70 points more than sham acupuncture. According to the needs of this study, we made alpha=0.05 and 1-beta=0.90, according to the formula: 
A two-sided test was performed. Through the query, =1.96, =1.282, and calculated n=33.32 34. In addition, considering the loss factor (according to a 20% loss rate), the final sample size was 41 subjects in each group, for 82 subjects in total.
Specialized statisticians who were independent of the research group generated 82 random numbers in SPSS 25.0 and then arranged these numbers in order from small to large. Numbers 1-41 were artificially specified as the acupuncture group, and 42-82 were specified as the sham acupuncture group. The random numbers are reproducible (random seed number: 20190520). Subjects entered the acupuncture group or the sham acupuncture group according to randomly assigned numbers at a ratio of 1:1 after signing the informed consent form. The random number and treatment plan corresponding to each subject were printed on a card and stored in an opaque envelope. Each subject who signed the informed consent form was given an envelope with their name, which was handed over to the acupuncturist during the treatment. The acupuncturist checked the envelope and removed the treatment card to view the treatment plan.
During the study, the generation of the random numbers list, subject recruitment, acupuncture treatment, outcome measure assessment and follow-up were performed independently by different researchers. Only the outside assistant and the acupuncturist were aware of the allocation. Participants and other relevant researchers were blinded to the allocation.
The statistics and analysis of all data were performed by two analytical researchers independent of the trial. Intention-to-treat (ITT) was used as the evaluation method to evaluate the results of the study. Statistical analysis of the data was performed using SPSS 25.0. The measurement data conformed to a normal distribution, and homogeneous variances were determined using the mean +- standard deviation to describe the central tendency and the degree of dispersion. The primary outcome assessments were analysed using a mixed-effect model for repeated measures (MMRM) with patients as a random-effect factor, treatment group, age, gender, time and comorbidities as the fixed variable, patients as the random variable, random effects including intercept, baseline as a covariable, age*group, gender*group, time*group and comorbidities*group as interaction effect using a first-order ante dependence covariance matrix. The comparison between groups used the independent sample t test, and the comparison of multiple time points within groups used repeated measurement data combined with multivariate variance analysis. For measurement data that did not conform to the normal distribution, the median, minimum, and maximum were given. The between-group comparisons used the Mann-Whitney U-test, and the within-group comparisons used the Friedman (F) test. Enumeration data were expressed as frequency and composition rate. For binary or multicategory nonranked data, comparisons between groups were performed by the chi2 test. If the data were ranked as ordinal data, the comparison between groups was performed by the Mann-Whitney U-test.
All statistical analyses used two-sided tests, and P values of <=.05 were considered statistically significant.