Adverse events of auricular therapy: a systematic review.
Being one of the most popular complementary therapeutic approaches, auricular therapy (AT) is defined as "a health care modality whereby the external surface of the ear, or auricle, is stimulated to alleviate pathological conditions in other parts of the body" . The earliest record of AT can trace back to 500 to 300 B.C. in ancient China, where the Yellow Emperor's Inner Canon (Huangdi Neijing) described that the ear is not isolated but intimately connected with the five viscera and the six bowels . The modern system of AT was developed by the French neurologist Paul Nogier in the late 1950s, and it is recognized that the outer ear has a somatotopic arrangement with an inverted fetus pattern and each internal organ is corresponding to a sensitive point located in the auricle . AT could produce a therapeutic effect for treating various types of disorders by stimulating the particular acupoint which corresponds to the targeted part of the body or organ . Various modalities are adopted in AT practice including auricular acupuncture, acupressure, moxibustion, injection, and auricular bloodletting therapy.
The WHO recognizes AT as a microacupuncture system that can produce a positive impact on regulating the whole body function , and its therapeutic effect has been investigated in a wide range of health problems in both oriental and western countries. Clinical trials and systematic reviews have shown that AT can be a promising modality in relieving preoperative anxiety , psychosomatic disorders , and various types of pain , managing hypertension  and cocaine dependence , and controlling obesity . The wide use of AT in clinical practice requires continual safety evaluation. It is said that the popularity of AT is partially attributed to its convenience and safety, and in some oriental countries, AT is usually conducted by healthcare professionals only with AT short-term training or even by unqualified practitioners without any experience in performing AT . However, this kind of intervention is not entirely risk-free, where adverse events, such as chest tightness, dizziness, perichondritis, and nausea, are also reported in the literature ; meanwhile, when applying AT to special populations such as pregnant women and immunocompromised patients, unwanted miscarriage and infection could have occurred .
The ear possesses abundant capillaries which make it highly vulnerable to skin inflammations and other infections . To minimize potential harms caused by AT, practitioners need to strictly follow standardized procedures of AT administration as well as fully understand the potential adverse events associated with it. It is important to assess the safety of AT in clinical practice. Unfortunately, different from other traditional therapies such as body acupuncture, moxibustion, and cupping, whose safety is well analyzed in surveys and/or systematic reviews [14-17], clinical evidence on the safety of AT has not been clearly established to date. Despite the increasing number of studies in recent years reporting harm data associated with AT, their results have not been systematically summarized. Up to now, there is no systematic review to evaluate the adverse events associated with AT. Therefore, the aim of this study was to evaluate the type and frequency of AT-related adverse events, to identify any avoidable adverse events associated with nonstandardized AT procedures, and to provide recommendations for future research and practice in this area.
A study protocol accompanied with a data extraction form was formulated and critically reviewed by two experts who were familiar with AT and systematic reviews before the initiation of the study.
2.1. Definition of Adverse Events. In this study, an adverse event was defined as "an undesirable experience associated with the use of a medical product in a patient" according to the US Food and Drug Administration 18]. A serious adverse event was defined when the event led to serious outcomes such as death, hospitalization, disability, and permanent damage or as being life-threatening .
2.2. Inclusion and Exclusion Criteria. Case reports, case series, prospective and retrospective surveys, and all types of clinical trials (randomized controlled trials, nonrandomized controlled clinical trials, or other uncontrolled clinical trials) reporting adverse events associated with AT in human subjects were included. Animal research, in vitro studies, and review papers were excluded. Types of AT could be auricular acupuncture, auricular electroacupuncture, auricular acupressure, auricular moxibustion, auricular injection, or auricular bloodletting therapy.
2.3. Data Sources and Searching Strategies. Relevant studies were retrieved from three sources: electronic database, manual search, and reference lists search for final included studies. Electronic search was conducted in 13 databases (from inception to May 8,2014) including PubMed, EMBase, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, PsycINFO, Allied and Complementary Medicine (AMED), Thomson Reuters Web of Science, Science Direct, Foreign Medical Journal Service (FMJS), China National Knowledge Infrastructure (CNKI), WanFang Data, Chinese Scientific Journal Database (CQVIP), and Chinese Biomedical Literature Database (CBM). No language restriction was applied for electronic search. Meanwhile, seven Chinese core journals on complementary medicine (Journal of Integrative Medicine, Chinese Acupuncture & Moxibustion, China Journal of Traditional Chinese Medicine and Pharmacy, Journal of Traditional Chinese Medicine, Chinese Journal of Basic Medicine in Traditional Chinese Medicine, Chinese Journal of Integrated Traditional and Western Medicine, Journal of Beijing University of Traditional Chinese Medicine, and Journal of Nanjing University of Traditional Chinese Medicine, issues within the latest three years) were manually retrieved for further relevant articles. Reference lists of the included papers were also checked to identify any potential eligible studies. All searches were conducted by two reviewers (Tan JY and Wang T) independently. Mesh terms, keywords, and free words such as "auriculotherapy," "acupuncture, ear," "adverse event*," "side effect*," "adverse effect*," "adverse health care event," "safe*," and "risk*" were used in the searching strategies. Table 3 presents three main search strategies for this review.
2.4. Study Selection and Data Extraction. Study characteristics and outcome data of each included article were extracted using the data extraction form, which included (1) first author, year of publication, study design, and setting; (2) participant characteristics (age, gender, sample size, diagnostic criteria, and reason for AT); (3) AT protocol (type of AT, practitioner, selected acupoints, type of AT equipment, and treatment duration); and (4) AT-related adverse events (type of adverse event, frequency, outcome, and causality). Study selection and data extraction were conducted by two reviewers independently, and disagreement was resolved through discussion.
2.5. Outcome Assessment. Type and frequency of AT-related adverse events were the main outcomes of this study. The likelihood of causality and quality of adverse events reporting were also judgedbytwo reviewers and checked by two experts specialized in AT and acupuncture.
For adverse events reported in case reports or case series, the likelihood of causality was judged by the WHOUppsala Monitoring Centre (UMC) System for Standardized Case Causality Assessment . The likelihood was classified into six grades including the following: (1) certain: a plausible time relationship that adverse events clearly occurred after receiving AT and disappeared after withdrawal, and these events could not be explained by other health problems or interventions; (2) probable/likely: a reasonable time relationship that the onset of symptoms was most likely related to AT and that was unlikely attributed to other health problems or interventions; (3) possible: a reasonable time relationship that the onset of symptoms was most likely related to AT but that could also be explained by other health problems or interventions, and the information on AT withdrawal was lacking or unclear; (4) unlikely: there was an improbable time relationship between AT and the adverse event; (5) conditional/unclassified: event occurred but more data were essential for a proper causality assessment; and (6) unassessable/unclassifiable: an adverse event was suggested by a report but cannot be judged due to insufficient or contradictory information .
For clinical trials, the quality of adverse events reporting was assessed using the CONSORT for Harms Data Recommendations [20, 21]. Seven items were employed for assessment [17,20,21]: (1) report of data on harms in the title or abstract; (2) report of AT-related harms in the introduction section; (3) prespecification of potential adverse events of AT (clinical and/or laboratory); (4) specification of approach for collecting harm-related information; (5) description of plans for presenting and analyzing adverse events of AT; (6) description of participant withdrawals due to adverse events of AT; and (7) report of the particular denominators for analyses on AT-related harms. The quality of each item was judged as "adequate," "partially adequate" "inadequate" or "not reported" accordingly . It was rated as "adequate" if an item was properly described in detail in the article or in the study protocol; "partially adequate" was given if an item was properly described but only in a brief format; when an item failed to be properly described, the quality was judged as "inadequate"; and "not reported" meant an item was not described .
3.1. Characteristics of Analyzed Studies. Electronic and manual searches yielded 8015 records. After checking by reference management software, 1187 duplicated records were removed, and another 6495 were further excluded after browsing the titles and abstracts. Full text of the remaining 333 records was retrieved for eligibility assessment, and 290 articles were finally excluded because they were reviews (n = 28), were study protocols (n = 5), were conference abstracts (n = 22), and were non-AT interventions (n = 34), and the adverse events were not reported (n = 201). Therefore, 43 studies [22-64] were identified for final analysis. The flow chart of study selection is presented in Figure 1.
The analyzed studies included 32 randomized controlled trials, five uncontrolled clinical trials, four case reports, and two nonrandomized controlled trials, with a total of 3396 participants receiving AT treatment. Six studies were from the United States, five from Taiwan, four from Germany, three from Hong Kong, two from Australia, two from Austria, two from the United Kingdom, 15 from China, and one each from Malaysia, Canada, Sweden, and Spain. Four AT modalities were utilized including auricular acupuncture in 18 studies [26-43], auricular acupressure in 21 studies [22-25,44-60], auricular electroacupuncture in three studies [61-63], and auricular bloodletting therapy in one study . AT was applied to deal with a variety of health problems such as drug dependence, smoking cessation, pain, constipation, insomnia, and obesity.
The clinical effectiveness of AT was descriptively summarized from the included 34 controlled clinical trials (randomized or nonrandomized) [26-32, 34-42, 44-50, 52-56, 58-63], as the data synthesis was not available due to the significant clinical heterogeneity in the types of disease, AT protocols, and intervention durations among analyzed trials. Twenty-three studies reported significantly positive effect of AT for the primary and/or secondary outcomes between groups, while eight studies only detected favorable changes within the AT groups. Of the controlled clinical trials that employed auricular acupuncture, 93.8% (15/16) stated positive outcomes of AT between or within groups, whereas it was 93.3% (14/15) in studies using auricular acupressure, respectively. Two out of three trials on auricular electroacupuncture showed clinical effectiveness of AT. The majority (30 studies) described the person who administered AT including acupuncturist, TCM practitioner, physician, psychiatrist, therapist, and nurse. The selection of acupoints for treatment was based on the targeted health problem but shenmen was the most commonly referred acupoint which was used in 35 studies for treating various types of disorders.
3.2. Case Reports. Table 1 presents AT-related adverse events reported in case reports. Four cases were located and the reported adverse events were dizziness in one case , somnolence in two cases [23, 24], and abdominal pain in one case . No serious adverse events were identified. All cases were treated with auricular acupressure using vaccaria seeds, whereas only two [22, 23] specified the practitioner who administered AT (a physician).
In Ye's report , a 48-year-old woman with constipation experienced dizziness five minutes after receiving auricular acupressure. The symptom gradually disappeared after removing the taped seeds. In two other reports [23, 24], two men (one was 41-year-old with lumbar muscle strain, and another was 43-year-old with dilated cardiomyopathy) reported drowsiness and somnolence at the 12th and 15th day, respectively, during the AT treatment. Their symptoms disappeared immediately after removing the taped seeds and reoccurred when seeds were taped again. Adverse events described in these three cases were assessed as probably/likely related to AT. In Ma's report , a 58-year-old woman with chronic diarrhea suffered from abdominal pain 30 minutes after receiving auricular acupressure, and the symptom disappeared immediately after removing the taped seeds. The author described it as a rare event caused by AT and the causality was assessed as possible.
3.3. Clinical Studies
3.3.1. Quality of Adverse Events Reporting. Table 2 presents AT-related adverse events reported in clinical trials. For the quality of adverse events reporting, the overall results were not optimal. Twenty studies adequately or partially adequately described adverse events in the title and/or abstract (51.3%), whereas there were only nine studies appropriately describing safety issues of AT in the introduction (23.1%). AT-related adverse events were seldom prespecified (17.9%), and 16 studies properly described approaches for adverse events data collection such as investigator observation, questionnaire, or self-report (41.0%). Only six studies properly described plans for presenting and analyzing adverse events (15.4%). Twelve studies adequately or partially adequately reported whether there were any subjects that withdrew due to adverse events of AT (30.8%), and 13 studies appropriately described the denominators for analyzing adverse events (33.3%).
3.3.2. Auricular Acupuncture-Related Adverse Events. Auricular acupuncture-related adverse events were reported in 18 clinical studies [26-43] with a total of 1753 participants receiving AT (Table 2). Duration of treatment varied among studies and 10 studies offered AT for more than three weeks. The most frequently reported adverse events were tenderness or pain at the needling site, dizziness, discomfort at the needling site, local bleeding, nausea, headache, and inflammation at insertion. Most of these events were transient, minor, and tolerable.
Eleven studies reported 134 cases complaining of local pain and tenderness at the needling site. AT was performed by acupuncturist in eight studies [27, 31, 32, 34-36, 38, 39], by psychiatrist and nurse in two studies [37, 41], and by physiotherapist in one study . Forty-three cases withdrew due to pain but the majority could tolerate AT and completed the treatment. Two studies [32, 35] did not take any measures to decrease adverse events and symptoms gradually declined, and one study  stopped AT temporarily or reduced treatment frequencies to deal with local pain.
Twenty-five cases in eight studies reported minor bleeding at insertion. AT was administered by an acupuncturist in five studies [27, 35, 38, 40, 42], by psychiatrist and nurse in two studies [37, 41], and by physiotherapist in one study . Bleeding often happened during inserting and/or withdrawing the needle and stopped soon without any treatment.
Seven studies [27, 29, 30, 35, 36, 42, 43] reported 51 cases experiencing dizziness after receiving auricular acupuncture; one study was conducted by a TCM practitioner  and one by an investigator with acupuncture diploma , while all others were carried out by acupuncturists. One study  took no action for dizziness and the symptom gradually disappeared, and three studies [36,42,43] reported that dizziness disappeared after removing the auricular stimulation, and only one case withdrew due to dizziness.
Minor nausea was reported in five studies (22 cases). AT was provided by an acupuncturist in four studies [27, 35, 36, 42] and by a TCM practitioner in one . Three studies [36, 42, 43] stated that nausea subsided after withdrawing the ear stimulation, one study  did not take any action, and the symptom gradually declined, whereas one study  failed to report the outcome. Two studies [27, 38] (AT performed by acupuncturist) reported 18 cases developing minor headache after AT, one did not report the outcome , and another stated that headache was resolved afterwards .
Two studies reported two cases experiencing minor inflammation (swelling or redness) around the needling site. AT was administered by an acupuncturist  and a physiotherapist , respectively. One study  stated that the subject who complained of swelling concealed a history of rheumatoid arthritis, which belonged to one of the exclusion criteria of that study. Twenty-seven cases in two studies [26, 29] reported discomfort or a strange feeling at insertion and one case withdrew. Only one study  reported minor infection around the needling site in one case and the condition gradually improved.
In addition, there were some other adverse events reported in a single study, including slight fever (19 cases) and dry mouth (15 cases), which focused on methadone maintenance treatment (MMT) for drug-dependent persons . Transient exacerbation of vasomotor symptoms (2 cases) was found in one study which focused on the vasomotor symptoms associated with luteinizing hormone releasing hormone agonist treatment in prostate cancer patients . Upper limb numbness was mentioned in one study  and it was resolved immediately after removing stimulation of acupoint "sympathetic."
3.3.3. Auricular Acupressure-Related Adverse Events. Auricular acupressure-related adverse events were reported in 17 clinical trials [44-60] (Table 2). A total of 1266 participants were treated with auricular acupressure (true or sham intervention) and the majority employed vaccaria seeds and/or magnetic pellets performing acupressure. More than half of the studies provided AT for no less than two weeks. The commonly reported adverse events were local skin irritation, discomfort, tenderness or pain at the taped site, and dizziness, and most of them were also mild, short-term, and well tolerated.
Thirteen studies [45, 47-50, 53-60] reported 63 cases suffering from local skin irritation with itchiness, allergy, or redness after receiving auricular acupressure. Only half of the studies specified the professional conducting AT, which include acupuncturist in two studies [53, 60], TCM practitioner in two studies [50, 58], therapist in one study , and nurse in the other one . Skin irritation was mostly attributed to the adhesive tapes. However, there was one study  reporting several subjects who were allergic to magnetic pellets. Seven cases withdrew due to skin irritation, and five cases changed adhesive tape to desensitization material and treatment continued, and those subjects who were allergic to magnetic pellets switched to vaccaria seeds and symptoms disappeared. Itchiness spontaneously subsided in 25 cases, and three cases recovered after treatment, while others tolerated well these symptoms and continued to complete treatment.
Three studies [51-53] reported tenderness or pain at the taped site (16 cases), and only two [51, 53] specified the AT practitioner (acupuncturist). No subjects withdrew, but one study  reported five cases experiencing obvious ear pain when receiving AT for the first time, and symptoms were relieved after reducing the pressing frequency and intensity of the taped seeds.
Two studies [46, 53] reported mild to moderate discomfort at the taped site (35 cases). Apart from one case that withdrew, others tolerated well the discomfort. Another two articles [45, 46] reported three cases experiencing minor dizziness during AT treatment and one subject withdrew. In one study  in which AT was administered by a nurse (the author did not declare whether the nurse had received any training in AT), ear skin breakdown was recorded in one subject, and the skin recovered two days later after using entoiodine. One study  reported pressure ulcers in the pinna in 18 subjects after receiving auricular acupressure and all ulcers healed within 10 days after removing the tapes.
3.3.4. Auricular Electroacupuncture-Related Adverse Events. Three articles [61-63] reported adverse events of auricular electroacupuncture (Table 2), which included 203 participants treated with true or sham AT. Treatment duration ranged from five to six weeks. Two studies described AT practitioners including a doctor with acupuncture experience in one  and nurse in another . Reported adverse events included discomfort and pain at insertion and local skin irritation. All reactions were mild and tolerable.
Two studies [62, 63] mentioned two cases complaining of discomfort at the needling site but the outcome was not reported. One study  reported mild ear skin irritation in eight cases, and the author explained it was induced by the adhesive patch of the P-stim or placebo device. Skin irritations were resolved immediately after AT. One study  found one case experiencing pain at the needling site but no outcome was reported.
3.3.5. Auricular Bloodletting Therapy-Related Adverse Events. There was only one study  using auricular bloodletting therapy and 170 subjects were included. Two cases reported minor infection at the needling site but the outcome was not described.
Our findings provide preliminary evidence that AT is a relatively safe approach in routine practice. The most frequently reported adverse events were mainly confined to short-term, mild, and tolerable reactions such as local discomfort, transient tenderness and pain, local skin irritation, minor bleeding, and dizziness. Some of them are potentially avoidable, and no serious adverse events were detected. However, the clinical practice of AT still needs caution because some adverse events like dizziness, somnolence, and infection could also result in serious negative outcomes. Meanwhile, the quality of adverse events reporting should be improved in future research and related guidelines such as the Guidelines for Case Reports of Adverse Events Related to Acupuncture , and the CONSORT for Harms Data Recommendations  should be followed.
Complementary therapeutic approaches such as body acupuncture, moxibustion, cupping, and AT have been widely used in dealing with a variety of disorders. Apart from the increasing emphasis on their therapeutic effects, safety of these interventions also received wide attention. The safety of body acupuncture has been well summarized in the literature and a number of serious adverse events have been identified including pneumothorax, hepatitis, staphylococcus infection, and central nervous system injuries . Adverse events of moxibustion were also systematically analyzed and some rare but dangerous events, for instance, burns, cellulitis, ecchymoma, and hepatitis C, were reported [14, 16]. In a recent systematic review , cupping-related adverse events reported in South Korea were investigated, and anemia, herpes viral infections, and skin lacerations were identified. In our findings, no serious adverse events of AT were reported and the reactions were mostly transient, mild, and tolerable. Based on our findings, the safety of AT seems superior to other traditional therapies such as body acupuncture, moxibustion, and cupping.
Various adverse events were identified in studies using auricular acupuncture, of which dizziness was one of the most commonly reported symptoms. Similar reports can also be found in body acupuncture [66-68], which viewed dizziness as mild symptoms of acupuncture-related fainting. This maybe because of transient hypotension, as acupuncture stimulation through the peripheral vagus nerve reflex could dilate the peripheral blood vessels and reduce venous return [68, 69]. As a result, decreasing in the brain blood supply induces transient hypotension and causes symptoms such as dizziness and weakness [68, 69]. Dizziness was often seen in people who received AT for the first time, especially for those who felt anxious or nervous before treatment and for those with extremely weak condition or with hypoglycemia . Although dizziness is generally mild and can spontaneously subside, potential risks associated with it still need caution, especially when applying AT in community or in clinical settings. Most clients there would leave the clinic immediately after finishing AT, and if dizziness occurs afterwards, accidental falls might happen. AT practitioners should pay attention to this issue, particularly for those elderly patients with osteoporosis.
As an invasive approach, auricular acupuncture may also lead to some infections. But from our findings, only one case was found with minor infection at insertion, and no serious infections such as chondritis, cellulitis, and hepatitis were detected. This finding is inconsistent with Norheim's study  which indicated that auricular chondritis was a commonly reported infection in patients receiving acupuncture on the ear. The infected cases came from the literature published 20-30 years ago, and the author concluded that the hygienic problem, such as insufficient needle skin disinfection, partially contributed to these infections . Unqualified sterilization and disinfection for either skin or needle equipment may be one of the crucial risk factors for acupuncture-related infections at that time. In our analyzed studies, the needles used in AT were generally sterilized and disposable, and the ear skin was mostly reported well disinfected. The gradually improved awareness of strict hygienic procedures during AT could be one of the reasons for the low incidence of infection identified in our review. However, practitioners also need to prudently use this approach on clients with poor wound-healing capacity, such as patients with diabetes mellitus, extremely weak status, or immunocompromised disorders , as potentially local damage could result in some nonhealing wounds or even systemic infections. Considering these circumstances, other noninvasive AT modalities such as auricular acupressure could be adopted instead.
It is worth noting that there were several rare adverse events reported in one trial in which the intervention group received AT plus MMT while the control group received MMT only . The author claimed that dry mouth and slight fever were AT-related adverse events. However, dry mouth is a general side effect of methadone , and sometimes fever is considered as one of the opioid withdrawal symptoms during the induction phase of MMT 72]. Unfortunately, the author did not measure methadone treatment-related side effects; therefore, comparison of reported adverse events between groups and causality assessment became impossible. It is difficult for us to distinguish whether these symptoms are caused by AT because the time relationship between symptom onset and the administration of AT was not reported, and the information on dechallenge and/or rechallenge was lacking.
Comparing with auricular acupuncture, auricular acupressure is noninvasive and much easier to access. In addition to qualified AT practitioners, auricular acupressure is also widely conducted by other healthcare professionals or even unqualified persons . In our analyzed studies, auricular acupressure was administered by acupuncturists, TCM practitioners, physicians, therapists, and registered nurses; however, more than half (52.4%) of the studies employing auricular acupressure failed to specify the person who performed AT, which made us unable to analyze whether there were any potentially avoidable adverse events caused by unqualified practitioners. In terms of the risk-benefit balance, either auricular acupuncture or auricular acupressure showed positive effects in managing a variety of health problems in our analyzed studies. However, for the adverse events, cases of local pain and dizziness were much less in auricular acupressure studies compared with those identified in studies on auricular acupuncture, and there were no bleeding and infection reports related to auricular acupressure. According to our findings, it seems that auricular acupressure is superior to other invasive AT approaches regarding its safety and convenience.
Adverse skin reactions, such as itchiness, redness, or allergy, were the most frequently reported adverse events in auricular acupressure, and the majority were associated with the adhesive tape used for taping acupressure seeds, while there were also some rare reports that skin irritation was caused by allergy to magnetic pellets. Despite the frequent complaints on skin irritations, these symptoms could be easily handled by changing adhesive tapes to desensitization textures or changing magnetic pellets to plant seeds. Dizziness was also reported in auricular acupressure, but the frequency was much lower than that reported in auricular acupuncture. In one case report , the author analyzed that dizziness might be due to the continual stimulation of the sympathetic nerve fibers wrapped around the vasa labyrinthi which could narrow blood vessels and reduce labyrinth's blood supply and, hence, lead to transient loss of orientation. This indicated that dizziness might be partially managed by reducing the frequency and intensity of acupressure.
Two case reports mentioned somnolence or drowsiness caused by auricular acupressure; the author in one study explained that it might be because of the long-term manipulation of the taped seeds inhibiting the normal functions of the autonomic nerve . These kinds of symptoms were also reported in body acupuncture treatment [66,73], and the activation of central 5-hydroxytryptamine (5-HT) pathways from the raphe nuclei may partially be involved in the onset of drowsiness after receiving acupoint stimulation, where stimulation of the raphe nuclei and the 5-HT secretion could contribute to the symptoms of fatigue, tiredness, and drowsiness [74, 75]. AT practitioners should attach importance to these reactions as somnolence or drowsiness could lead to some dangerous outcomes such as drowsiness-related motor vehicle crash. It is noteworthy that one study  reported 18 cases of pressure ulcers. Auricular acupressure in this study was administered by doctors and nurses who had received training in AT. Pressure ulcers were possibly caused by the long treatment duration and continual pressure. Participants in this study received weekly AT consecutively for 8 weeks; auricular implants were kept for seven days during each treatment and participants were asked to press them three times daily. No rest period was mentioned between each treatment and the continual stimulated auricle skin might have not had enough time to heal.
AT-related harms in auricular electroacupuncture and bloodletting therapy were all transient and mild. However, this review cannot ascertain the safety of these two modalities because only four studies with a limited sample size were included for analysis, and the methodological quality of adverse events reporting was unsatisfactory.
Several limitations were identified in our analyzed articles, which could affect the strength of the evidence concluded from our findings. Participant sample sizes included in this review were relatively small, and one-third of the analyzed studies failed to specify the practitioner conducting AT. Quality of adverse events reporting in included clinical trials was generally unsatisfactory, the majority did not prespecify AT-related adverse events, more than half failed to report approaches for collecting and analyzing adverse events, time relationship between the onset of symptoms and the administration of AT was not clearly described, and one-third failed to report outcomes of adverse events, all of which made it difficult to evaluate the causality of adverse events reported in clinical trials. Also, it is noted that several types of needles were utilized in studies on auricular acupuncture, and some adverse events may be associated with the variations on the length and thickness of particular AT needle, depth of insertion, and the frequency and intensity of manual pressing on the needled area. However, the information was described insufficiently in the analyzed studies, which inhibited us to judge whether there were any adverse events associated with particular types of AT equipment and procedure. Meanwhile, certain information such as the particular AT practitioner, patient's medical history, details of AT procedure and equipment, and the adverse events outcome also failed to be reported clearly in the included case reports. Moreover, there was a possibility that AT-related adverse events were underreported because during the process of the literature sorting we found a great number of papers not including adverse events as the study outcome. In addition, case reports on AT-related adverse events were rare in the published literature which made us unable to access any new or previously unrecognized harms associated with AT.
This review itself also has some limitations. Although we have made efforts to retrieve all the relevant literature, the included studies were only English and Chinese articles, and language bias may occur. Meanwhile, as there is no specific tool for the causality assessment of adverse events reported in acupuncture (including AT) studies, we employed the tool developed by the WHO-UMC in this review; however, this tool is particularly designed for adverse drug reactions and some items might not be sensitive enough for evaluating acupuncture or AT-related adverse events. Furthermore, the originally designed outcome on the frequency of AT-related adverse events was finally not calculated, as the majority of the included literature only reported the absolute number of cases complaining of adverse events.
5. Implications for Future Research and Practice
This study has some implications for future research and practice. Firstly, invasive AT approaches such as auricular acupuncture (manual or electric), and bloodletting therapy, should be applied by qualified practitioners. Even for the one administering noninvasive AT like auricular acupressure, receiving AT training from a qualified practitioner before application is essential because nonstandardized practice could create more unintended harms to patients. Secondly, the patients' condition needs to be well assessed before applying AT. Practitioners should identify beforehand if any clients are allergic to steel needles, adhesive tapes, magnetic pellets, or other AT materials. For weakened or elderly patients undergoing AT, semireclining position should be adopted to prevent potential harm induced by dizziness, and invasive AT should be applied with caution on patients with poor wound-healing capacity. Thirdly, the importance of patients' education should be emphasized, and the informed consent should be provided before AT. Patients need to be well informed about the potential risks associated with adverse events such as dizziness, somnolence, and drowsiness. Working at heights or driving should be avoided if patients are undergoing AT treatment. Fourthly, treatment duration and pressure intensity of AT need to be reasonably arranged. Patients should avoid putting excessive pressure on the implanted needles or taped seeds, and de qi sensation (a subjective feeling of numbness, pressure sensation, heaviness, soreness, or distension) could be adopted as an indicator of stopping pressure. For those receiving long-term AT treatment, a reasonable rest period between each treatment course should be provided. Moreover, for future case reports on AT-related adverse events, more details on the qualification of the practitioner, the targeted auricular acupoints, the AT equipment, the instruction on manual press, the position of the patient during AT, and the outcome of adverse events should be fully reported, and related guideline such as the Guidelines for Case Reports of Adverse Events Related to Acupuncture could be considered . Lastly, prospective or retrospective surveys on AT-related adverse events are needed in future research to gather practitioner-reported and/or patient-reported outcomes. Future clinical trials on AT should include safety assessment as an important outcome measure, and related international guidelines such as the CONSORT for Harms Data Recommendations  should be followed to report and analyze AT-related adverse events.
This systematic review did not receive any grants from any funding agencies.
Conflict of Interests
The authors declare that there is no conflict of interests regarding the publication of this paper.
Jing-Yu Tan undertook the study design, completed the literature searching and data extraction and analysis, and drafted and revised this paper. Alexander Molassiotis undertook the study design and critically revised this paper. Tao Wang completed the literature searching and data extraction. Lorna K. P Suen undertook the study design and revised this paper.
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Jing-Yu Tan, (1) Alexander Molassiotis, (1) Tao Wang, (2) and Lorna K. P. Suen (1)
(1) School of Nursing, The Hong Kong Polytechnic University, HungHom, Kowloon, Hong Kong
(2) The Second Affiliated People's Hospital, Fujian University of Traditional Chinese Medicine, No. 13 Hudong Road, Gulou District, Fuzhou 350003, China
Correspondence should be addressed to Lorna K. P. Suen; email@example.com
Received 24 June 2014; Revised 26 August 2014; Accepted 27 August 2014; Published 10 November 2014
Academic Editor: Byung-Cheul Shin
Table 1: Adverse events associated with auricular therapy reported in case reports. Study and setting Age (gender) Reason for AT Ye, 2014 , 48 (female) Constipation Chinese PLA General Hospital, Beijing, China Yu and Xie, 41 (male) Lumbar muscle 2010 , strain Teda Hospital, Tianjin, China Huo et al., 43 (male) Dilated 2000 , Chinese cardiomyopathy PLA 546 Hospital, Xinjiang, China Ma, 1992 , 58 (female) Chronic Ningyang TCM diarrhea Hospital, Shandong, China Study and setting Type of AT Practitioner (method and duration) Ye, 2014 , Method: auricular Physician Chinese PLA General acupressure using Hospital, Beijing, auricular plaster with China vaccaria seeds Duration: not reported Yu and Xie, Method: auricular Physician 2010 , acupressure using Teda Hospital, auricular plaster with Tianjin, China vaccaria seeds Duration: three days per treatment, 4 treatments in total (12 days) Huo et al., Method: auricular Not reported 2000 , Chinese acupressure using PLA 546 Hospital, auricular plaster with Xinjiang, China vaccaria seeds Duration: three days per treatment, 5 treatments in total (15 days) Ma, 1992 , Method: auricular Not reported Ningyang TCM acupressure using Hospital, Shandong, auricular plaster with China vaccaria seeds Duration: 30 minutes Study and setting Selected acupoints AEs and severity Ye, 2014 , Shenmen, kidney, liver, Event(s): dizziness Chinese PLA General spleen, stomach, temple, Severity: Hospital, Beijing, subcortex, forehead, not reported China occiput Yu and Xie, Heart, liver, spleen, Event(s): somnolence 2010 , occiput, shenmen, Severity: Teda Hospital, sympathetic not reported Tianjin, China Huo et al., Heart, liver, lung, Event(s): somnolence 2000 , Chinese shenmen, spleen, Severity: PLA 546 Hospital, sympathetic, occiput not reported Xinjiang, China Ma, 1992 , Large intestine, Event(s): abdominal Ningyang TCM small intestine, shenmen, pain Severity: Hospital, Shandong, liver, sympathetic, severe China spleen Study and setting Outcomes Causality * Ye, 2014 , Recovery after Probable/likely Chinese PLA General removing taped seeds Hospital, Beijing, China Yu and Xie, Recovery after Probable/likely 2010 , removing taped seeds Teda Hospital, Tianjin, China Huo et al., Recovery after Probable/likely 2000 , Chinese removing taped seeds PLA 546 Hospital, Xinjiang, China Ma, 1992 , Recovery after Possible Ningyang TCM removing taped seeds Hospital, Shandong, China AT: auricular therapy, AE: adverse event, PLA: Peoples Liberation Army, and TCM: traditional Chinese medicine. * The WHO-Uppsala Monitoring Centre (UMC) System for Standardized Case Causality Assessment: certain-a plausible time relationship that adverse events clearly occurred after receiving AT and disappeared after withdrawal, and these events could not be explained by other health problems or interventions; probable/likely-a reasonable time relationship that the onset of symptoms was most likely related to AT and that was unlikely attributed to other health problems or interventions; possible-a reasonable time relationship that the onset of symptoms was most likely related to AT but that could also be explained by other health problems or interventions, and the information at withdrawal was lacking or unclear; unlikely-there was an improbable time relationship between AT and the adverse event; conditional/unclassified-event occurred but more data were essential for a proper causality assessment; unassessable/unclassifiable-an adverse event was suggested by a report but cannot be judged due to insufficient or contradictory information. Table 2: Adverse events associated with auricular therapy reported in clinical trials. Study Reason Intervention for AT and (details of AT) practitioner and control Studies on auricular acupuncture Intervention (true AT): Prisco et al., (i) Method: auricular 2013  R: PTSD-related acupuncture with spring RCT (N = 35) insomnia handle needles Department of P: physician (0.16 x 15 mm) Veterans Affairs (ii) Duration: two Medical Center, treatments weekly (45 Washington DC, USA minutes per treatment) for 8 weeks Control 1 (sham AT): auricular acupuncture at nonacupuncture points Control 2: waiting-list control Intervention (MMT + AT): Lua and Talib, 2013 (i) Method: auricular  RCT (N = 97) acupuncture Three Methadone R: drug (needles: 0.25 x Maintenance dependence 12.55 mm) Treatment (MMT) P: acupuncturist (ii) Duration: three Centers, Terengganu, treatments weekly Malaysia (30 minutes per treatment) for 8 weeks Control: MMT only Intervention (exercise + AT): Hunter et al., 2012 (i) Method: auricular  RCT (N = 52) R: chronic acupuncture with Seirin Primary Care & A low back pain Pyonex ear needles University P: (1.80 x 0.26 mm) Population, physiotherapist (ii) Duration: one Northern Ireland, treatment (48 hours) UK weekly for 6 weeks Control: exercise only Intervention (true AT): (i) Method: auricular Michalek-Sauberer R: state anxiety acupuncture (needles: et al., 2012  before dental 0.2 x 15 mm) RCT (N = 182) treatment (ii) Duration: twenty Outpatient Clinic, P: investigator minutes until the start Medical University with a diploma of dental treatment of Vienna, Vienna, of acupuncture Control 1 (sham AT): Austria auricular acupuncture at nonspecific points Control 2: no intervention Intervention (true AT): (i) Method: auricular acupuncture (needles: Lien et al., R: obesity 2 mm tip and 10 mm 2012  P: acupuncturist annular-shaped body) RCT (N = 90) (ii) Duration: three Taipei City treatments weekly Hospital, Taiwan for 4 weeks Control 1: auricular stimulation using magnetic pellets Control 2 (sham AT): needles with the tips removed Intervention (true AT): (i) Method: auricular Hsu et al" 2009  R; obesity acupuncture (needles: RCT (N = 60) P: acupuncturist 2 mm tip and 10 mm Taipei Hospital, annular-shaped body) (ii) Taiwan Duration: two treatments weekly (3 days per treatment) for 6 weeks Control (sham AT): needles with the tips removed Wang et al., 2009 R: pregnant women Intervention (true AT):  RCT (N = 159) with low back (i) Method: auricular Yale-New Have pain and acupuncture with Seirin Hospital, New posterior pelvic Pyonex ear needles Haven, USA pain (ii) Duration: one week P: acupuncturist Control 1 (sham AT): auricular acupuncture at nonspecific points Control 2: no treatment Harding et al., R: hot flushes Intervention (AT): (i) 2008  Non-RCT in prostate Method: auricular (N = 60) James Cook cancer patients acupuncture with 0.20 g University Hospital, with LHRH agonist sterile single-use Middlesbrough, UK treatment needles P: not reported (ii) Duration: weekly treatment (40 minutes) for 10 weeks Control: not applicable Courbasson et al., R: women with Intervention (AT + usual 2007  Non-RCT concurrent treatment): (N = 305) The Jean substance use (i) Method: auricular Tweed Centre, problems and acupuncture (details not Toronto, Ontario, anxiety and described) Canada depressive (ii) Duration: three symptoms treatments weekly P: acupuncturist (45 minutes per treatment) (length of treatment not mentioned) Control: usual treatment Wu et al., 2007  R: smoking Intervention (true AT): RCT (?? = 131) cessation (i) Method: auricular Smoking Cessation P: acupuncturist acupuncture with 36 Clinics, Taipei gauge 0.5 inch ear- Veterans General piercing needles Hospital, Taiwan (ii) Duration: weekly treatment for 8 weeks Control (sham AT): auricular acupuncture at nonspecific points Intervention Usichenko et al., (true AT + analgesia): 2007  (i) Method: auricular RCT (N = 120) acupuncture with Ambulatory R: postoperative indwelling steel needles Orthopedic Surgery pain (0.22 x 1.5 mm) Center of the Ernst P: acupuncturist (ii) Duration: inserted Moritz Arndt before surgery and kept University, until the following Greifswald, Germany morning Control (sham AT + analgesia): auricular acupuncture at nonacupuncture points Intervention Kunz et al., 2007 (AT + usual treatment):  RCT (N = 109) R: alcohol (i) Method: auricular Clinic of withdrawal acupuncture with Psychiatry and P: psychiatrists stainless-steel Psychotherapy or mental-health acupuncture needles Bethel, Bielefeld, nurses (0.2 x 0.15 mm) Germany (ii) Duration: daily treatment (45 minutes) for 5 consecutive days Control: aromatherapy + usual treatment Intervention (true AT + analgesia): Usichenko et al., (i) Method: auricular 2005  RCT acupuncture with (N = 61) Department R: postoperative permanent press steel of Anesthesiology pain needles (0.22 x 1.5 mm) and Orthopedic P: acupuncturist (ii) Duration: inserted Surgery, University the evening before of Greifswald, surgery and kept for Germany 3 days after surgery Control (sham AT + analgesia): auricular acupuncture at nonacupuncture points Intervention (true AT): (i) Method: auricular Berman et al., R: drug use acupuncture with 2004  problem, stainless-steel RCT (N = 158) psychological disposable needles Two Medium-Security symptoms, and (0.22 x 0.13 mm) Institutions physical (ii) Duration: a total (Jails), Sweden discomfort in of 14 treatments prison inmates (40 minutes per P: acupuncturist treatment) for 4 weeks Control (sham AT): auricular acupuncture at nonspecific points Intervention 1 R: smoking (true acupuncture + Bier et al., 2002 cessation and education):  RCT (N = 141) cigarette (i) Method: auricular Arizona, USA consumption acupuncture with 36 P: acupuncturist gauge 0.5 inch needles (ii) Duration: five treatments weekly (30 minutes per treatment) for 4 weeks Intervention 2 (true acupuncture) Control (sham acupuncture + education): auricular acupuncture at nonacupuncture points Intervention Gurevich et al., R: substance- (receiving AT for 5 or 1996  Non-RCT abuse problem more times): (N = 77) North Shore P: psychiatrist (i) Method: auricular University Hospital and nurses acupuncture with sterile at Glen Cove, USA disposable needles (ii) Duration: daily treatment (20-40 minutes) Control: receiving AT for 4 or fewer times Intervention (true AT + support Washburn et al., R: heroin service): 1993  addiction (i) Method: auricular RCT (N = 100) P: acupuncturist acupuncture with The Bayview-Hunters single-use disposable Point Foundation, needles San Francisco, USA (ii) Duration: twenty-one days (20-45 minutes per treatment) Control (sham AT + support service): auricular acupuncture at nonacupuncture points Intervention (AT): Zhang and Fan, 1986 (i) Method: auricular  Non-RCT acupuncture for main (N = 179) TCM R: cholecys- points and auricular Academy of Shanxi tolithiasis acupressure for adjunct Province, China P: TCM points (details were practitioner not described) (ii) Duration: not reported Control: not applicable Studies on auricular acupressure Intervention (true AT): (i) Method: auricular Vas et al, 2014 R: chronic acupressure using  RCT (N = 265) nonspecific auricular plaster with Ten Primary spinal pain vaccaria seeds Healthcare Centres, P: doctors and (ii) Duration: weekly Seville, Spain nurses with treatment (seeds kept AT training for 7 days) for 8 weeks Control (placebo AT): auricular acupressure using auricular plaster with inactive black plastic discs Intervention (true AT): (i) Method: auricular Li et al, 2014  acupressure using RCT (N = 99) R: constipation auricular plaster with Elderly Residential P: not reported magnetic pellets Care Home, (ii) Duration: ten days Hong Kong Control 1 (placebo AT): auricular acupressure using auricular plaster with vaccaria seeds Control 2 (usual care): auricular acupressure using auricular plaster only Intervention (true AT): (i) Method: auricular acupressure with stain Zhang et al., 2013 R: smoking less-steel press-pellet  RCT (N = 43) cessation tapes RMIT University, P: acupuncturist (ii) Duration: weekly Australia treatment for 8 weeks Control (sham AT): auricular acupressure at nonspecific points Intervention (AT + intravenous analgesia): Kong, 2012  R: postoperative (i) Method: auricular RCT (N = 60) pain acupressure using Foshan Hospital of P: not reported auricular plaster with TCM, Foshan, vaccaria seeds China (ii) Duration: one treatment (5 hours after surgery), seeds kept for 3 days Control: intravenous analgesia only Intervention (true AT + Yeh et al., 2012 R: chemotherapy- standard care):  RCT (N = 10) induced nausea (i) Method: auricular A Large Childrens and vomiting acupressure using Hospital, Taiwan P: therapist auricular plaster with plant seeds (ii) Duration: one treatment, seeds kept for 7 days Control (sham AT + standard care): auricular acupressure at nonspecific points Intervention (true AT): (i) Method: auricular Li et al., 2012  acupressure using RCT (N = 39) auricular plaster with Elderly Residential R: constipation magnetic pellets Care Home, P: not reported (ii) Duration: three Hong Kong weeks Control (placebo AT): auricular acupressure using auricular plaster with vaccaria seeds Intervention (AT): (i) Method: auricular Jin et al., 2012 acupressure using  RCT (N = 80) auricular plaster with Cangnan TCM R: severe magnetic pellets Hospital of insomnia (ii) Duration: one Zhejiang Province, P: TCM treatment, seeds kept Cangnan, China practitioner for 7 days Control: standardized medication Intervention (AT): (i) Method: auricular Kung et al., 2011 R: women with acupressure using  Non-RCT postmenopausal auricular plaster with (N = 45) Taipei insomnia magnetic pellets Veterans General P: acupuncturist (ii) Duration: daily Hospital, Taiwan treatment (every night before sleep) for 4 weeks Control: not applicable Intervention Xia et al., 2011 (AT + Chinese medicine  RCT (N = 60) plaster): Baoan Hospital R: low back pain (i) Method: auricular Affiliated to caused by lumbar acupressure using South Medical strain auricular plaster with University, P: not reported vaccaria seeds Shenzhen, China (ii) Duration: two treatments weekly for 2 weeks Control: Chinese medicine plaster only Intervention (true AT): (i) Method: auricular Xue et al., 2011 acupressure using  R: persistent auricular plaster with RCT (N = 63) allergic stain less-steel pellets Two Metropolitan rhinitis (ii) Duration: eight RMIT Campus in P: acupuncturist weeks Melbourne, Control (sham AT): Australia auricular acupressure at nonspecific points Intervention Ji et al., 2010  (AT + usual care): RCT (N = 73) R: functional (i) Method: auricular Shuguang Hospital constipation acupressure using Affiliated to P: nurse auricular plaster with Shanghai University Liu Shen Wan of TCM, Shanghai, (for excess syndrome) or China magnetic pellets (for deficiency syndrome) (ii) Duration: one month Control: usual care Intervention (true AT + hand Wing et al., 2010 acupressure):  RCT (N = 70) (i) Method: auricular Outpatient Clinics R: smoking acupressure using and The Community, cessation auricular plaster with Hong Kong P: not reported hard beads (ii) Duration: three weeks Control (sham AT + sham hand acupressure): auricular acupressure at nonmeridian points Sun, 2010  Intervention RCT (N = 173) R: insomnia (AT + psychological Department of TCM, P: not reported support): Xuzhou First (i) Method: auricular Hospital of Jiangsu acupressure using Province, Xuzhou, auricular plaster with China vaccaria seeds (ii) Duration: twenty days Control: AT only Intervention (AT): (i) Method: auricular Peng, 2009  acupressure using Non-RCT (N = 30) auricular plaster with Hanguang Hospital R: neurasthenia magnetic pellets of Handan City, P: not reported (ii) Duration: three Handan, China days per treatment, 20 treatments in total (60 days) Control: not applicable Chen et al., 2009 Intervention (AT):  RCT (N = 180) R: vascular (i) Method: auricular TCM Hospital of dementia acupressure using Hainan Province, P: TCM auricular plaster with Haikou, China practitioner vaccaria seeds (ii) Duration: daily treatment for 12 weeks Control: standardized medication Wang et al., Intervention (AT): 2007  (i) Method: auricular RCT (N = 198) R: myopia acupressure using Peoples Hospital of P: not reported auricular plaster with Baoshan City, vaccaria seeds Baoshan, China (ii) Duration: four weeks for one treatment Control: standardized medication Ding et al., 2006 Intervention (AT +  Neiguan acupressure): RCT (N = 200) R: motion (i) Method: auricular TCM Hospital of sickness acupressure using Hebei Province, P: acupuncturist auricular plaster with Shijiazhuang, China magnetic pellets (ii) Duration: not reported Control: standardized medication Studies on auricullar electroacupuncture Schukro et al., Intervention (AT + diet 2013  based on TCM): RCT (N = 56) (i) Method: auricular Department of R: obesity acupuncture with Special Anesthesia in female electrical stimulation and Pain Management patients using P-stim at the Medical P: not reported electroacupuncture device University of (needle: 27 gauge, Vienna, Vienna, 3 mm length) Austria (ii) Duration: 4-day treatment per week for 6 weeks Control (placebo AT + diet based on TCM): auricular acupuncture with a P-stim dummy Intervention (AT): (i) Method: auricular Fritz et al., acupuncture with the 2013  Stim Flex 400A RCT (N = 125) R: smoking Transcutaneous Electrical St. Louis Veterans cessation Nerve Stimulation Unit Affairs Medical P: registered (active, 80 Hz) Center, USA nurse (ii) Duration: weekly treatment (20 minutes per treatment) for 5 consecutive weeks Control (sham AT): auricular acupuncture with the Stim Flex 400A Transcutaneous Electrical Nerve Stimulation Unit (inactive, 0 Hz) Bernateck et al., Intervention (AT): 2008  (i) Method: auricular RCT (N = 44) acupuncture with Outpatient Clinic R: rheumatoid electrical stimulation of the Department arthritis using P-stim device of Rheumatology, P: doctor with (needle: 27 gauge, Hannover profound 3 mm length) Medical School, acupuncture (ii) Duration: weekly Hannover, Germany experience treatment (48 hours per treatment) for 6 weeks Control: autogenic training Studies on auricular bloodletting therapy Yuan and Qiao, Intervention (AT): 1998  Non-RCT R: acute (i) Method: auricular (N = 170) Chinese tonsillitis bloodletting therapy PLA 34260 Hospital, P: not reported with three-edged needle Xiangfan, China (ii) Duration: not applicable Control: not applicable Study Selected acupoints AEs (number of Cases) of AT and outcome True AT: shenmen, Prisco et al., liver, kidney, 2013  sympathetic, Uncomfortable at RCT (N = 35) hippocampus Sham the needling site Department of AT: nonacupuncture (n = 1) Veterans Affairs points located on Outcome: withdrawal Medical Center, the helix of the Washington DC, USA ear Light headache Lua and Talib, 2013 (ft = 17) Slight  RCT (N = 97) bleeding (n = 14) Three Methadone Shenmen, Tingling sensations Maintenance sympathetic, kidney, (n = 19) Pain Treatment (MMT) liver, lung (ft = 17) and nausea Centers, Terengganu, (ft = 19) Drowsiness Malaysia (ft = 11) and dizziness (n = 19) Dry mouth (ft = 15) and slight fever (ft = 19) Outcome: not reported Pain and redness (not reported) Hunter et al., 2012 Minor bleeding  RCT (N = 52) Shenmen, lumbar (not reported) Primary Care & A spine, cushion Swelling around the University needling site Population, (n = 1)# Outcome: Northern Ireland, (i) NR (for pain, UK redness, and bleeding) (ii) Recovery (for swelling) Michalek-Sauberer True AT: et al., 2012  relaxation, Warmth or a strange RCT (N = 182) tranquilizer, feeling at the Outpatient Clinic, master cerebral treated ear or Medical University Sham AT: tonsil, dizziness (ft = 26) of Vienna, Vienna, finger, shoulder Outcome: Austria not reported Lien et al., Shenmen, stomach, Dizziness (ft = 1) 2012  hunger, endocrine Outcome: withdrawal RCT (N = 90) Taipei City Hospital, Taiwan Minor inflammation Hsu et al" 2009  Shenmen, stomach, at the needling RCT (N = 60) hunger, endocrine site (n = 1) Mild Taipei Hospital, tenderness at the Taiwan needling site (n = 9) Outcome: not reported Wang et al., 2009 True AT: shenmen,  RCT (N = 159) kidney, analgesia Yale-New Have Sham AT: shoulder, Transient ear Hospital, New wrist, extra- tenderness (n = 4) Haven, USA auricular point Outcome: resolved spontaneously Harding et al., 2008  Non-RCT Transient (N = 60) James Cook Shenmen, liver, exacerbation of University Hospital, lung, autonomic, vasomotor symptoms Middlesbrough, UK kidney (n = 2) Outcome: resolved spontaneously (lasted only seconds) Courbasson et al., 2007  Non-RCT (N = 305) The Jean Experiencing pain Tweed Centre, Not reported from needles Toronto, Ontario, (not reported) Canada Outcome: not reported Wu et al., 2007  Hematoma (n = 1) RCT (?? = 131) True AT: shenmen, Feeling of residual Smoking Cessation lung, mouth, needling (n = 24) Clinics, Taipei sympathetic Tenderness sensation Veterans General Sham AT: eye, elbow, (n = 50) Minor Hospital, Taiwan shoulder, knee bleeding (n = 3) Minor infection (n = 1) Nausea (n = 2) and dizziness (n = 4) Outcome: gradually declined Dizziness and Usichenko et al., True AT: shenmen, nausea (n = 1) 2007  lung, knee joint Pain at insertion RCT (N = 120) points located and sleep Ambulatory on the helix disturbance (n = 1) Orthopedic Surgery Outcome: Center of the Ernst (i) Disappeared Moritz Arndt after withdrawal of University, the needles Greifswald, Germany (for dizziness and nausea) (ii) Not reported (for pain and sleep disturbance) Kunz et al., 2007  RCT (N = 109) Shenmen, Pain and mild Clinic of sympathetic, kidney, bleeding (n = 6) Psychiatry and liver, lung Outcome: not Psychotherapy reported Bethel, Bielefeld, Germany Pain at the needling site (n = 3) Minor Usichenko et al., True AT: shenmen, bleeding at the 2005  RCT lung, thalamus, needling site (N = 61) Department hip joint (n = 2) Headache of Anesthesiology Sham AT: (n = 1) and Orthopedic nonacupuncture Hip pain after Surgery, University points on the needle withdrawal of Greifswald, auricular helix (n = 2) Outcome: Germany (i) One withdrew, not reported for another 2 (for pain) (ii) Recovery after treatment (for bleeding) (iii) Recovery after surgery (for headache) (iv) Not reported (for hip pain) Berman et al., True AT: shenmen, Pain at insertion 2004  lung, liver, kidney, (n = 44) RCT (N = 158) sympathetic Outcome: forty-two Two Medium-Security Sham AT: nonspecific dropped out and 2 Institutions points on the completed treatment (Jails), Sweden auricular helix even though they found it painful True AT: shenmen, Infrequent minor Bier et al., 2002 lung, liver, kidney, bleeding upon  RCT (N = 141) sympathetic needle removal Arizona, USA Sham AT: (not reported) nonacupuncture Outcome: not points located reported within 5 mm of the true points Minor local Gurevich et al., bleeding 1996  Non-RCT (not reported) (N = 77) North Shore Shenmen, lung, Local pain University Hospital liver, kidney, (not reported) at Glen Cove, USA sympathetic Outcome: (i) Treatment was not required (for bleeding) (ii) Stopped AT temporarily or had less frequent treatments (for local pain) True AT: shenmen, Slight bleeding at Washburn et al., lung, insertion 1993  Sham AT: (not reported) RCT (N = 100) nonacupuncture Mild nausea and The Bayview-Hunters points located dizziness Point Foundation, close to the true (not reported) San Francisco, USA points Outcome: relief when the needles were removed Zhang and Fan, 1986  Non-RCT Liver, gallbladder, Dizziness, upper (N = 179) TCM stomach, duodenum, limb numbness, and Academy of Shanxi shenmen, minor nausea Province, China sympathetic, lung (not reported) Outcome: disappeared after removing stimulation on acupoint "sympathetic" Studies on auricular acupressure Pressure ulcers in Main acupoints: the pinna (n = 18) Vas et al, 2014 shenmen, thalamus Worsened symptoms  RCT (N = 265) Adjunct acupoints: (n = 8) Outcome: Ten Primary not reported (i) Healed within Healthcare Centres, 10 days of removal Seville, Spain (for pressure ulcers) (ii) Not reported (for worsened symptoms) Minor local Large intestine, itchiness (n = 27) Li et al, 2014  rectum, San Jiao, Minor dizziness RCT (N = 99) spleen, lung, (n = 2) Outcome: Elderly Residential sympathetic, (i) Spontaneously Care Home, subcortex subsided after AT Hong Kong (25) and 2 withdrew (for itchiness) (ii) Spontaneously subsided after AT (1) and 1 withdrew (for dizziness) Mild to moderate local discomfort True AT: shenmen, (n = 5) Zhang et al., 2013 lung, mouth, extra, Slight headache and  RCT (N = 43) liver dizziness (n = 1) RMIT University, Sham AT: helix 2, Outcome: Australia shoulder, clavicle, (i) All AEs were occiput, tooth resolved without any medical intervention (for both) (ii) One subject withdrew (for ear discomfort) Kong, 2012  RCT (N = 60) Shenmen, liver, Mild skin Foshan Hospital of kidney, heel, irritation (n = 2) TCM, Foshan, lesser occipital Outcome: no obvious China nerve, great discomfort and auricular nerve AT continued Yeh et al., 2012 True AT: Shenmen,  RCT (N = 10) sympathetic, Local itchiness A Large Childrens cardia, stomach, (n = 3) Hospital, Taiwan digestive subcortex Outcome: continued Sham AT: external to complete the knee point, vision, study shoulder joint, eye Li et al., 2012  RCT (N = 39) Large intestine, Mild, tolerable, Elderly Residential rectum, San Jiao, and short-term Care Home, spleen, lung, itchiness of the Hong Kong sympathetic, ears (n = 7) subcortex Outcomes: not reported Main acupoints: shenmen, occiput, Jin et al., 2012 subcortex, Local redness at  RCT (N = 80) sympathetic the taped site Cangnan TCM Adjunct acupoints: (n = 2) Hospital of (based on TCM Outcome: recovery Zhejiang Province, syndrome) heart, after treatment Cangnan, China spleen, kidney, liver, stomach Kung et al., 2011  Non-RCT (N = 45) Taipei Shenmen, kidney, Sensation of Veterans General heart, brainstem, auricular Hospital, Taiwan subcortex tenderness (n = 2) Outcome: not reported Xia et al., 2011 Obvious pain at the  RCT (N = 60) taped site when Baoan Hospital Ashi point, kidney, receiving AT for the Affiliated to liver, lumbosacral first time (n = 5) South Medical vertebrae, shenmen, Outcome: completed University, subcortex the study Shenzhen, China by reducing pressing frequency and intensity True AT: shenmen, Mild to moderate Xue et al., 2011 internal nose, lung, local and short-term  wind stream discomfort (n = 30) RCT (N = 63) Sham AT: adrenal Sore ear (n = 9) Two Metropolitan gland, helix 2, Ear itch (n = 7) RMIT Campus in shoulder, clavicle, Outcome: well Melbourne, occiput, teeth tolerated Australia Main acupoints: Ji et al., 2010  large intestine, Mild redness and RCT (N = 73) small intestine, skin breakdown at Shuguang Hospital rectum Adjunct the taped site Affiliated to acupoints: Lung, (n = 1) Outcome: Shanghai University San Jiao, stomach recovery two days of TCM, Shanghai, (for excess later after using China syndrome), spleen, entoiodine kidney, endocrine (for deficiency syndrome) True AT: shenmen, Wing et al., 2010 lung, month, brain Skin irritation  RCT (N = 70) Non meridian points: (allergy) at the Outpatient Clinics away from those site of the adhesive and The Community, selected for the tapes (n = 3) Hong Kong treatment group Outcome: withdrawal Main acupoints: Sun, 2010  shenmen, Skin irritation RCT (N = 173) sympathetic, (allergy) at the Department of TCM, endocrine, heart, site of the adhesive Xuzhou First subcortex Adjunct tapes (n = 5) Hospital of Jiangsu acupoints: liver, Outcome: changed to Province, Xuzhou, stomach, spleen, desensitization China kidney, pancreas tapes and treatment and gallbladder, continued heart of dorsal surface Main acupoints: shenmen, subcortex, Skin allergy and Peng, 2009  endocrine, anterior itchiness of the Non-RCT (N = 30) ear lobe ear (not reported) Hanguang Hospital Adjunct acupoints: Outcome: symptom of Handan City, (based on TCM disappeared after Handan, China syndrome) liver, changing magnetic gallbladder, pellets to vaccaria San Jiao, stomach, seeds lung, heart Chen et al., 2009  RCT (N = 180) Severe skin allergy TCM Hospital of Shenmen, brain, and itchiness at Hainan Province, kidney, occiput the taped site Haikou, China (n = 2) Outcome: withdrawal Wang et al., 2007  Skin allergy and RCT (N = 198) Apex of ear, kidney, local redness at Peoples Hospital of liver, eye, eye 2, the taped site Baoshan City, spleen, (n = 2) Baoshan, China Outcome: not reported Ding et al., 2006  RCT (N = 200) Stomach, occiput, Itchiness at the TCM Hospital of shenmen, sympathetic taped site (n = 2) Hebei Province, Outcome: Shijiazhuang, China not reported Studies on auricullar electroacupuncture Schukro et al., 2013  mild skin RCT (N = 56) irritations behind Department of the ear caused by Special Anesthesia Hunger, stomach, the adhesive patch and Pain Management colon of the P-stim/ at the Medical placebo device University of (n = 8) Outcome: Vienna, Vienna, resolved Austria immediately after the end of application Fritz et al., 2013  Auricle discomfort RCT (N = 125) Lung, shenmen, without redness or St. Louis Veterans nicotine, point zero, swelling (n = 1) Affairs Medical palate Outcome: Center, USA not reported Bernateck et al., 2008  RCT (N = 44) Outpatient Clinic Shenmen, cushion, Pain and discomfort of the Department an individual point at the needling of Rheumatology, depending on the site (n = 1) Hannover main pain spots Outcome: Medical School, not reported Hannover, Germany Studies on auricular bloodletting therapy Yuan and Qiao, 1998  Non-RCT Minor infection at (N = 170) Chinese Helix 6 (Ashi point) the needling site PLA 34260 Hospital, (n = 2) Xiangfan, China Outcome: not reported Study Quality of AEs Reporting * (1) Not reported Prisco et al., (2) Not reported 2013  (3) Not reported RCT (N = 35) (4) Not reported Department of (5) Not reported Veterans Affairs (6) Adequate Medical Center, (7) Not reported Washington DC, USA (1) Adequate Lua and Talib, 2013 (2) Adequate  RCT (N = 97) (3) Not reported Three Methadone (4) Adequate Maintenance (5) Adequate Treatment (MMT) (6) Inadequate Centers, Terengganu, (7) Adequate Malaysia (1) Adequate (2) Not reported Hunter et al., 2012 (3) Not reported  RCT (N = 52) (4) Not reported Primary Care & A (5) Not reported University (6) Inadequate Population, (7) Partially adequate Northern Ireland, UK (1) Not reported (2) Not reported Michalek-Sauberer (3) Not reported et al., 2012  (4) Not reported RCT (N = 182) (5) Not reported Outpatient Clinic, (6) Not reported Medical University (7) Not reported of Vienna, Vienna, Austria (1) Adequate (2) Partially adequate Lien et al., (3) Not reported 2012  (4) Not reported RCT (N = 90) (5) Not reported Taipei City (6) Adequate Hospital, Taiwan (7) Not reported (1) Adequate (2) Not reported Hsu et al" 2009  (3) Not reported RCT (N = 60) (4) Not reported Taipei Hospital, (5) Not reported Taiwan (6) Adequate (7) Not reported Wang et al., 2009 (1) Not reported  RCT (N = 159) (2) Not reported Yale-New Have (3) Adequate Hospital, New (4) Adequate Haven, USA (5) Not reported (6) Not reported (7) Partially adequate Harding et al., (1) Adequate 2008  Non-RCT (2) Not reported (N = 60) James Cook (3) Not reported University Hospital, (4) Not reported Middlesbrough, UK (5) Not reported (6) Adequate (7) Partially adequate Courbasson et al., (1) Not reported 2007  Non-RCT (2) Inadequate (N = 305) The Jean (3) Not reported Tweed Centre, (4) Partially adequate Toronto, Ontario, (5) Not reported Canada (6) Inadequate (7) Not reported Wu et al., 2007  (1) Adequate RCT (?? = 131) (2) Not reported Smoking Cessation (3) Adequate Clinics, Taipei (4) Adequate Veterans General (5) Adequate Hospital, Taiwan (6) Inadequate (7) Adequate (1) Not reported Usichenko et al., (2) Not reported 2007  (3) Not reported RCT (N = 120) (5) Partially adequate Ambulatory (7) Adequate Orthopedic Surgery Center of the Ernst Moritz Arndt University, Greifswald, Germany (1) Not reported Kunz et al., 2007 (2) Not reported  RCT (N = 109) (3) Not reported Clinic of (4) Adequate Psychiatry and (5) Partially adequate Psychotherapy (6) Inadequate Bethel, Bielefeld, (7) Adequate Germany (1) Not reported (2) Not reported Usichenko et al., (3) Not reported 2005  RCT (4) Not reported (N = 61) Department (5) Inadequate of Anesthesiology (6) Adequate and Orthopedic (7) Inadequate Surgery, University of Greifswald, Germany (1) Adequate (2) Adequate Berman et al., (3) Adequate 2004  (4) Adequate RCT (N = 158) (5) Partially adequate Two Medium-Security (6) Inadequate Institutions (7) Adequate (Jails), Sweden (1) Not reported (2) Not reported Bier et al., 2002 (3) Not reported  RCT (N = 141) (4) Adequate Arizona, USA (5) Not reported (6) Inadequate (7) Not reported (1) Partially adequate Gurevich et al., (2) Inadequate 1996  Non-RCT (3) Partially adequate (N = 77) North Shore (4) Not reported University Hospital (5) Not reported at Glen Cove, USA (6) Partially adequate (7) Not reported (1) Not reported (2) Inadequate Washburn et al., (3) Partially adequate 1993  (4) Not reported RCT (N = 100) (5) Not reported The Bayview-Hunters (6) Inadequate Point Foundation, (7) Not reported San Francisco, USA (1) Not reported Zhang and Fan, 1986 (2) Not reported  Non-RCT (3) Not reported (N = 179) TCM (4) Not reported Academy of Shanxi (5) Not reported Province, China (6) Inadequate (7) Not reported Vas et al, 2014 (1) Adequate  RCT (N = 265) (2) Adequate Ten Primary (3) Not reported Healthcare Centres, (4) Adequate Seville, Spain (5) Inadequate (6) Inadequate (7) Partially adequate (1) Partially adequate (2) Partially adequate Li et al, 2014  (3) Adequate RCT (N = 99) (4) Not reported Elderly Residential (5) Inadequate Care Home, (6) Adequate Hong Kong (7) Partially adequate (1) Adequate (2) Adequate (3) Not reported Zhang et al., 2013 (4) Adequate  RCT (N = 43) (5) Inadequate RMIT University, (6) Adequate Australia (7) Partially adequate (1) Adequate (2) Partially adequate Kong, 2012  (3) Not reported RCT (N = 60) (4) Adequate Foshan Hospital of (5) Partially adequate TCM, Foshan, (6) Inadequate China (7) Inadequate (1) Not reported Yeh et al., 2012 (2) Not reported  RCT (N = 10) (3) Not reported A Large Childrens (4) Not reported Hospital, Taiwan (5) Not reported (6) Inadequate (7) Not reported (1) Not reported (2) Not reported Li et al., 2012  (3) Not reported RCT (N = 39) (4) Partially adequate Elderly Residential (5) Not reported Care Home, (6) Inadequate Hong Kong (7) Not reported (1) Inadequate (2) Not reported Jin et al., 2012 (3) Not reported  RCT (N = 80) (4) Adequate Cangnan TCM (5) Not reported Hospital of (6) Inadequate Zhejiang Province, (7) Not reported Cangnan, China (1) Not reported (2) Not reported Kung et al., 2011 (3) Not reported  Non-RCT (4) Not reported (N = 45) Taipei (5) Not reported Veterans General (6) Inadequate Hospital, Taiwan (7) Not reported (1) Adequate Xia et al., 2011 (2) Not reported  RCT (N = 60) (3) Partially adequate Baoan Hospital (4) Partially adequate Affiliated to (5) Not reported South Medical (6) Inadequate University, (7) Not reported Shenzhen, China (1) Not reported (2) Not reported Xue et al., 2011 (3) Not reported  (4) Partially adequate RCT (N = 63) (5) Not reported Two Metropolitan (6) Inadequate RMIT Campus in (7) Inadequate Melbourne, Australia (1) Adequate Ji et al., 2010  (2) Not reported RCT (N = 73) (3) Not reported Shuguang Hospital (4) Adequate Affiliated to (5) Not reported Shanghai University (6) Inadequate of TCM, Shanghai, (7) Not reported China (1) Adequate (2) Partially adequate Wing et al., 2010 (3) Not reported  RCT (N = 70) (4) Not reported Outpatient Clinics (5) Not reported and The Community, (6) Adequate Hong Kong (7) Partially adequate (1) Not reported Sun, 2010  (2) Not reported RCT (N = 173) (3) Not reported Department of TCM, (4) Not reported Xuzhou First (5) Not reported Hospital of Jiangsu (6) Inadequate Province, Xuzhou, (7) Not reported China (1) Not reported (2) Not reported Peng, 2009  (3) Not reported Non-RCT (N = 30) (4) Not reported Hanguang Hospital (5) Not reported of Handan City, (6) Inadequate Handan, China (7) Not reported (1) Adequate Chen et al., 2009 (2) Partially adequate  RCT (N = 180) (3) Not reported TCM Hospital of (4) Inadequate Hainan Province, (5) Not reported Haikou, China (6) Adequate (7) Not reported (1) Adequate Wang et al., (2) Not reported 2007  (3) Not reported RCT (N = 198) (4) Not reported Peoples Hospital of (5) Not reported Baoshan City, (6) Inadequate Baoshan, China (7) Not reported (1) Adequate Ding et al., 2006 (2) Not reported  (3) Not reported RCT (N = 200) (4) Not reported TCM Hospital of (5) Not reported Hebei Province, (6) Inadequate Shijiazhuang, China (7) Not reported Schukro et al., (1) Adequate 2013  (2) Not reported RCT (N = 56) (3) Not reported Department of (4) Not reported Special Anesthesia (5) Not reported and Pain Management (6) Inadequate at the Medical (7) Not reported University of Vienna, Vienna, Austria (1) Adequate Fritz et al., (2) Not reported 2013  (3) Not reported RCT (N = 125) (4) Partially adequate St. Louis Veterans (5) Not reported Affairs Medical (6) Partially adequate Center, USA (7) Partially adequate Bernateck et al., (1) Not reported 2008  (2) Not reported RCT (N = 44) (3) Not reported Outpatient Clinic (4) Not reported of the Department (5) Not reported of Rheumatology, (6) Inadequate Hannover (7) Not reported Medical School, Hannover, Germany (1) Not reported Yuan and Qiao, (2) Not reported 1998  Non-RCT (3) Not reported (N = 170) Chinese (4) Not reported PLA 34260 Hospital, (5) Not reported Xiangfan, China (6) Inadequate (7) Not reported AT: auricular therapy, AE: adverse event, RCT: randomized controlled trial, R: reason for AT, PTSD: posttraumatic stress disorder, P: practitioner, LHRH: luteinizing hormone releasing hormone, and TCM: traditional Chinese medicine. * The CONSORT Recommendation for AEs: (1) report of data on harms in the title or abstract, (2) report of AT-related harms in the introduction section, (3) prespecification of potential adverse events of AT (clinical and/or laboratory), (4) specification of approach for collecting harms-related information, (5) description of plans for presenting and analyzing adverse events of AT, (6) description of participant withdrawals due to adverse events of AT, and (7) report of the particular denominators for analyses on AT-related harms. Quality grades for each item: adequate-item was properly described in detail in the article or in the study protocol; partially adequate-item was properly described but only in a brief format; inadequate-item failed to be properly described; not reported-item was not described. #Happened in one participant who did not disclose a history of rheumatoid arthritis (one of the exclusion criteria for that study). Table 3: Selected searching strategies for the systematic review. Searching strategies ID PubMed Records #1 "auriculotherapy"[MeSH Terms] OR "acupuncture, 264 ear"[MeSH Terms] #2 ((((((((((((((((((auriculotherap* [Title/ 35299 Abstract]) OR (acupunctur* [Title/Abstract] AND ear* [Title/Abstract])) OR (acupunctur* [Title/Abstract] AND auricu* [Title/Abstract])) OR (acupressur* [Title/Abstract] AND ear* [Title/Abstract])) OR (acupressur* [Title/ Abstract] AND auricu* [Title/Abstract])) OR (auricu* [Title/Abstract] AND poin* [Title/ Abstract])) OR (ear[Title/Abstract] AND poin* [Title/Abstract])) OR (auricu* [Title/Abstract] AND acupoin* [Title/Abstract])) OR (ear[Title/ Abstract] AND acupoin* [Title/Abstract])) OR (auricu* [Title/Abstract] AND plaster* [Title/Abstract])) OR (massag* [Title/Abstract] AND ear* [Title/Abstract])) OR (ear[Title/Abstract] AND plaster* [Title/Abstract])) OR (massag* [Title/Abstract] AND auricu* [Title/Abstract])) OR (magne* [Title/Abstract] AND ear* [Title/ Abstract])) OR (magne* [Title/Abstract] AND auricu* [Title/Abstract])) OR otopoin* [Title/ Abstract]) OR vaccaria* [Title/Abstract]) OR erxue[Title/Abstract] #3 #1 OR #2 35338 #4 (((((("adverse event* "[Title/Abstract]) 1608414 OR "adverse effect* "[Title/Abstract]) OR "adverse reaction* "[Title/Abstract]) OR "side effect* "[Title/Abstract]) OR "complication*" [Title/Abstract]) OR "safe*"[Title/Abstract]) OR "risk* "[Title/Abstract] #5 #3 AND #4 4284 EMBase #1 auriculotherap* :ab,ti OR (ear NEAR/3 9599 acupunctur*):ab,ti OR (auricu* NEAR/3 acupunctur*):ab,ti OR (ear NEAR/3 acupressur*): ab,ti OR (auricu*NEAR/3 acupressur*):ab,ti OR (auricu* NEAR/3 poin*):ab,ti OR 'auricular plaster':ab,ti OR (ear NEAR/3 plaster*):ab,ti OR (ear NEAR/3 poin*):ab,ti OR (auricu* NEAR/3 acupoint*):ab,ti OR (ear NEAR/3 acupoint*):ab,ti OR otopoin*:ab,ti OR (vaccaria* NEAR/15 ear*): ab,ti OR (vaccaria* NEAR/15 auricu*):ab,ti OR (massag* NEAR/3 auricu*):ab,ti OR (massag* NEAR/3 ear*):ab,ti OR (cowherb NEAR/15 ear*):ab,ti OR (cowherb NEAR/15 auricu*):ab,ti OR (magne* NEAR/15 ear*):ab,ti OR (magne* NEAR/15 auricu*):ab,ti OR erxue*:ab,ti #2 (adverse NEAR/3 event*):ab,ti OR (adverse NEAR/3 3092250 effect*):ab,ti OR (adverse NEAR/3 reaction*):ab,ti OR (side NEAR/3 effect*):ab,ti OR complication*: ab,ti OR safe*:ab,ti OR risk*:ab,ti #3 #1 AND #2 1688 CENTRAL #1 MeSH descriptor: [Auriculotherapy] explode 126 all trees #2 MeSH descriptor: [Acupuncture, Ear] 120 explode all trees #3 auriculotherap* or (ear near/3 acupunctur*) or 864 (auricu* near/3 acupunctur*) or (ear near/3 acupressur*) or (auricu* near/3 acupressur*) or (auricu* near/3 poin*) or (ear near/3 poin*) or (ear near/3 plaster*) or (auricu* near/3 plaster*) or (auricu* near/3 acupoint*) or (ear near/3 acupoint*) or otopoint* or (vaccaria* near/15 ear) or (vaccaria* near/15 auricu*) or (cowherb near/15 ear*) or (cowherb near/15 auricu*) or (magne* near/15 ear*) or (magne* near/15 auricu*) or (massag* near/3 ear*) or (massag* near/3 auricu*) or erxue*:ti,ab,kw (Word variations have been searched) #4 #1 OR #2 OR #3 864 #5 complication* or (adverse near/3 event*) or 240648 (adverse near/3 effect*) or (adverse near/3 reaction*) or (side near/3 effect*) or safe* or risk*: ti,ab,kw (Word variations have been searched) #6 #4 AND #5 182 #7 #6 in Trials 158