OBJECTIVE: To investigate the effect of acupuncture on advanced cancer patients by meta-analysis. METHODS: Nine databases (the Cochrane Central Register of Controlled Trials, MEDLINE, Web of Science, Embase, China National Knowledge Infrastructure, the Cumulative Index to Nursing and Allied Health Literature, Chinese Biomedical Literature Database, China Science and Technology Journal Database, and WanFang Data) were searched for randomized controlled trials (RCTs) on acupuncture in advanced cancer patients published from inception to February 13, 2023 and updated to June 1, 2023. Primary outcomes were quality of life (QOL), while secondary outcomes were pain, fatigue, and adverse events (side effects). Data synthesis was performed using RevMan V.5.3 to calculate pooled effect sizes. RoB-2 was used for the risk of bias, and the quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) tool. RESULTS: Totally 17 RCTs involving 1,178 participants were included, 15 of which were pooled for meta-analysis. Most studies demonstrated some concern for the overall risk of bias. The pooled data indicated that acupuncture was associated with improved QOL [mean difference (MD)=6.67, 95% confidence interval (CI): 5.09 to 8.26], pain (MD=-1.18, 95% CI -2.28 to -0.08), and adverse events (risk ratio=0.30, 95% CI: 0.26 to 0.57) compared with control groups. Fatigue outcome was not included. Heterogeneity was substantial, and GRADE evidence was very low for both QOL and pain. CONCLUSIONS Acupuncture could benefit patients with advanced cancer and is considered safe compared with usual care. However, the evidence regarding QOL and pain outcomes requires further validation. It is crucial to encourage the development of high-quality studies to strengthen this evidence. (Registry No. CRD42023423539).
Humans ; Acupuncture Therapy ; Neoplasms/therapy* ; Quality of Life ; Randomized Controlled Trials as Topic ; Treatment Outcome

Various acupuncture clinical trials have been conducted on migraine; however, the conclusions remain controversial especially when acupuncture was compared with sham acupuncture. Sham acupuncture is sometimes performed at the same acupuncture points used for verum acupuncture despite the evidence on acupuncture point specificity. Four databases were searched for sham acupuncture or waiting list-controlled acupuncture trials for migraine on December 25, 2023. Sham acupuncture was classified according to the needling points: sham acupuncture therapy at verum points (SATV) or at sham points (SATS). Network meta-analysis was performed based on the frequentist framework for headache pain intensity and response rate. A total of 18 studies involving 1936 participants were analyzed. Headache pain intensity and response rate were significantly improved in verum acupuncture compared with SATS. However, there was no significant difference between SATV and verum acupuncture. When comparing SATS and SATV, there was no significant difference in headache pain intensity and response rate; however, the results were in favor of SATV. The effect of the risk of bias on the certainty of evidence between verum and sham acupunctures was judged to be generally low. SATV should not be misused as a placebo control to evaluate the efficacy of acupuncture.
Humans ; Migraine Disorders/therapy* ; Acupuncture Therapy/methods* ; Acupuncture Points ; Treatment Outcome ; Randomized Controlled Trials as Topic

OBJECTIVE: To explore whether hydrocortisone can improve the prognosis of patients with severe community-acquired pneumonia (sCAP) by Meta-analysis. METHODS: Randomized controlled trial (RCT) on hydrocortisone in the treatment of sCAP were extracted from the database including PubMed, Cochrane library, Web of Science, and Embase, and the search time was up to April 29, 2023. The patients in the standard treatment group received standard treatment such as antibiotics and supportive care, while those in the hydrocortisone group received hydrocortisone treatment on the basis of standard treatment. Meta-analysis was used to compare the mortality, duration of mechanical ventilation, mechanical ventilation rate and incidence of adverse reactions (hyperglycemia, gastrointestinal bleeding, secondary infection) between the two groups. The risk of literature bias was assessed. The studies that might have publication bias were corrected by the subtraction and complementation method. At the same time, trial sequential analysis (TSA) was conducted. RESULTS: A total of 5 RCTs involving 1 031 patients were finally enrolled, including 494 patients in the standard treatment group and 537 patients in the hydrocortisone group. Among the 5 studies, the research site of 2 studies was in the mixed ward. Considering the inclusion characteristics of the study population, there was doubt whether its research object was sCAP patients, which might have a certain impact on the results and introduce potential bias. Meta-analysis showed that the mortality in the hydrocortisone group was significantly lower than that in the standard treatment group [6.0% vs. 14.0%; odds ratio (OR) = 0.38, 95% confidence interval (95%CI) was 0.25-0.59, P < 0.01; I² = 9%]. The studies that were asymmetric were corrected by the reduction and supplementation method. Even after filling the missing studies, hydrocortisone could still reduce the death risk of the patient (OR = 0.49, 95%CI was 0.32-0.73, P < 0.01; I² = 31%). TSA showed that the average mortality of the standard treatment group was about 14.0%, and that of the hydrocortisone group was about 6.0%, with a relative risk reduction (RRR) = 57%. The calculated sample size was 699 cases, and the actual sample size was 1 031 cases. The actual sample size exceeded the required sample size, and the Z-curve crossed the O'Brien-Fleming boundary and the curve corresponding to P = 0.05, it meant that hydrocortisone could effectively reduce the mortality of sCAP. Compared with the standard treatment group, no statistical difference in the duration of mechanical ventilation was found in the hydrocortisone group [mean difference (MD) = -3.26, 95%CI was -6.72-0.21, P = 0.07; I² = 0%], but the 8-day mechanical ventilation rate was significantly lowered (19.5% vs. 55.4%; OR = 0.24, 95%CI was 0.12-0.45, P < 0.01; I² = 0%), and also no significantly difference was found in the incidence of hyperglycemia (54.3% vs. 44.6%, OR = 1.26, 95%CI was 0.56-2.84, P = 0.58; I² = 61%), gastrointestinal bleeding (2.5% vs. 3.6%; OR = 0.70, 95%CI was 0.34-1.46, P = 0.34; I² = 0%) and secondary infection (9.2% vs. 11.5%; OR = 0.46, 95%CI was 0.06-3.35, P = 0.45; I² = 53%). CONCLUSION Hydrocortisone can reduce the mortality rate of sCAP patients, decrease their need for mechanical ventilation, and does not increase the risk of hyperglycemia, gastrointestinal bleeding, or secondary infections.
Humans ; Hydrocortisone/therapeutic use* ; Community-Acquired Infections/drug therapy* ; Pneumonia/drug therapy* ; Randomized Controlled Trials as Topic ; Respiration, Artificial ; Community-Acquired Pneumonia

Progressive pulmonary fibrosis (PPF) is a progressive and lethal condition with few effective treatment options. Improvements in quality of life for patients with PPF remain limited even while receiving treatment with approved antifibrotic drugs. Traditional Chinese medicine (TCM) has the potential to improve cough, dyspnea and fatigue symptoms of patients with PPF. TCM treatments are typically diverse and individualized, requiring urgent development of efficient and precise design strategies to identify effective treatment options. We designed an innovative Bayesian adaptive two-stage trial, hoping to provide new ideas for the rapid evaluation of the effectiveness of TCM in PPF. An open-label, two-stage, adaptive Bayesian randomized controlled trial will be conducted in China. Based on Bayesian methods, the trial will employ response-adaptive randomization to allocate patients to study groups based on data collected over the course of the trial. The adaptive Bayesian trial design will employ a Bayesian hierarchical model with "stopping" and "continuation" criteria once a predetermined posterior probability of superiority or futility and a decision threshold are reached. The trial can be implemented more efficiently by sharing the master protocol and organizational management mechanisms of the sub-trial we have implemented. The primary patient-reported outcome is a change in the Leicester Cough Questionnaire score, reflecting an improvement in cough-specific quality of life. The adaptive Bayesian trial design may be a promising method to facilitate the rapid clinical evaluation of TCM effectiveness for PPF, and will provide an example for how to evaluate TCM effectiveness in rare and refractory diseases. However, due to the complexity of the trial implementation, sufficient simulation analysis by professional statistical analysts is required to construct a Bayesian response-adaptive randomization procedure for timely response. Moreover, detailed standard operating procedures need to be developed to ensure the feasibility of the trial implementation. Please cite this article as: Zhang C, Nie YS, Zhang CT, Yang HJ, Zhang HR, Xiao W, Cui GF, Li J, Li SJ, Huang QS, Yan SY. An adaptive Bayesian randomized controlled trial of traditional Chinese medicine in progressive pulmonary fibrosis: Rationale and study design. J Integr Med. 2025; 23(2): 138-145.
Female ; Humans ; Male ; Bayes Theorem ; Disease Progression ; Drugs, Chinese Herbal/therapeutic use* ; Medicine, Chinese Traditional/methods* ; Pulmonary Fibrosis/therapy* ; Quality of Life ; Randomized Controlled Trials as Topic ; Research Design ; Adaptive Clinical Trials as Topic

BACKGROUND: Over 65 million people have long COVID. Evidence for using Chinese herbal medicine (CHM) to treat long COVID is growing. A systematic review of evidence for guiding clinical decision is warranted. OBJECTIVE: To examine the effects and safety of CHM in alleviating the severity of dyspnea, fatigue, exercise intolerance, depression, anxiety and insomnia in long COVID adults based on registered randomized clinical trials (RCT). SEARCH STRATEGY: World Health Organization International Clinical Trials Registry Platform and Chinese Clinical Trial Registry were searched for registered trial protocols from database inception to February 10, 2023. English (PubMed, Embase, AMED and CINAHL) and Chinese databases (CNKI, Wanfang Data and CQVIP) were then searched to identify relevant publications from December 2019 through April 6, 2023. INCLUSION CRITERIA: Registered RCTs that compared the effects of Chinese herbal medicines or Chinese herbal formulas against a control treatment (i.e., the placebo or usual care) in adults with persistent symptoms of long COVID. The primary outcome of dyspnea, and secondary outcomes of fatigue, exercise intolerance, depression, anxiety and insomnia were measured using validated tools at the end of the treatment. DATA EXTRACTION AND ANALYSIS: Data were extracted, and eligible RCTs were evaluated using version 2 of the Cochrane risk-of-bias tool for randomized trials and Grading of Recommendations, Assessment, Development and Evaluations independently by two researchers. Effect sizes were estimated by random-effects modelling and mean difference (MD). Heterogeneity between trials was quantified by I². RESULTS: Among the 38 registered clinical trials we identified, seven RCTs (1,519 patients) were included in the systematic review. One RCT had a low overall risk of bias. Compared to the control, CHM reduces dyspnea on the Borg Dyspnea Scale score (MD = -0.2, 95% confidence interval [CI] = -0.65 to 0.25) with moderate certainty, and reduces fatigue on the Borg Scale (MD = -0.48, 95% CI = -0.74 to -0.22) with low certainty. CHM clinically reduces depression on Hamilton Depression Rating Scale score (MD = -6.00, 95% CI = -7.56 to -4.44) and anxiety on Hamilton Anxiety Rating Scale score (MD = -6.10, 95% CI = -7.67 to -4.53), and reduces insomnia on the Insomnia Severity Index (MD = -4.86, 95% CI = -12.50 to 2.79) with moderate certainty. Meta-analysis of two RCTs (517 patients) showed that CHM clinically improves exercise intolerance by increasing 6-minute walking distance (MD = -15.92, 95% CI = -10.20 to 42.05) with substantial heterogeneity (I² = 68%) and low certainty. CONCLUSION CHM is associated with a post-treatment clinical reduction in depression and anxiety in long COVID adults, compared to the control, but it does not have a strong treatment effect on dyspnea and insomnia. Effects of CHM on exercise intolerance and fatigue are uncertain, and the safety of using CHM remains questionable. Please cite this article as: Tsang MS, Zhou IW, Zhang AL, Xue CC. Chinese herbal medicine for dyspnea and persistent symptoms of long COVID: A systematic review and meta-analysis of randomized controlled trials. J Integr Med. 2025; 23(2): 126-137.
Humans ; Dyspnea/etiology* ; Drugs, Chinese Herbal/therapeutic use* ; Randomized Controlled Trials as Topic ; COVID-19/complications* ; Fatigue/drug therapy* ; SARS-CoV-2 ; Anxiety/drug therapy* ; Depression/drug therapy* ; Sleep Initiation and Maintenance Disorders/drug therapy* ; Betacoronavirus

BACKGROUND: Acupuncture has shown potential therapeutic benefits for individuals with simple obesity. However, some researchers argue that some of the effectiveness of acupuncture may be due to the placebo response. OBJECTIVE: To understand the placebo response of acupuncture treatment in simple obesity, a systematic review and meta-analysis was designed based on the comparison between sham acupuncture before and after treatment. SEARCH STRATEGY: Eight databases (PubMed, Web of Science, Cochrane Library, Embase, China National Knowledge Infrastructure, Wanfang Database, China Biology Medicine Database, and Chinese Scientific Journals Database) were searched from inception to August 1, 2023. The MeSH search terms comprised obesity and acupuncture. INCLUSION CRITERIA: Randomized controlled trials (RCTs) using sham or placebo acupuncture as a control in treating obesity were enrolled. DATA EXTRACTION AND ANALYSIS: Two researchers independently extracted data, and the results were cross-checked after completion. Each RCT's detailed sham/placebo acupuncture treatment protocol was assessed according to the SHam Acupuncture REporting guidelines. The revised Cochrane risk-of-bias tool for randomized trials and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system were used to determine the risk of bias and quality of evidence, respectively. Body mass index (BMI) was defined as the primary outcome. Anthropometric parameters and laboratory test parameters related to obesity were defined as secondary outcomes. We used standardized mean difference (SMD) with 95% confidence interval (CI) to calculate treatment effects of outcomes. RESULTS: Fifteen RCTs with a total of 1250 patients were included. The BMI significantly decreased after treatment in the sham acupuncture group compared to baseline (SMD 0.37, 95% CI 0.09-0.66; I² = 81%, random model; P < 0.01). Treatment duration (P = 0.02) and other interventions significantly impacted the placebo response rate (P = 0.00). CONCLUSION The placebo response of sham acupuncture was strong in the RCTs for simple obesity, and the effect sizes differed between various outcomes. The treatment duration and other interventions emerged as potential influencing factors for the placebo response of sham acupuncture. Please cite this article as: Liu KJ, Jiao RM, Ji J, Yao WW, Han CR, Zhao XY, Zhao JJ. Placebo response in sham acupuncture therapy trials for simple obesity: a systematic review and meta-analysis. J Integr Med. 2025; 23(3): 264-273.
Humans ; Acupuncture Therapy/methods* ; Obesity/therapy* ; Placebo Effect ; Placebos ; Randomized Controlled Trials as Topic

BACKGROUND: A growing body of research is exploring the role of antioxidant and anti-inflammatory dietary supplements in the treatment of osteoarthritis, highlighting an increasing emphasis on non-pharmacological interventions. Although more patients are turning to supplements to manage osteoarthritis, their actual effectiveness remains uncertain. OBJECTIVE: This study aims to provide a comprehensive evaluation of the available evidence concerning the efficacy of various dietary supplements in osteoarthritis treatment. SEARCH STRATEGY: We searched PubMed, Embase, Cochrane Library and Web of Science for studies on the use of various dietary supplements in the treatment of osteoarthritis from the creation of each database until Jan 20, 2025. INCLUSION CRITERIA: (1) Research object: osteoarthritis. (2) Intervention measures: patients in the treatment group received dietary supplements, while the control group received placebos. (3) Research type: randomized controlled trials (RCTs). DATA EXTRACTION AND ANALYSIS: Two researchers independently examined the literature and retrieved data based on predefined criteria. The information gathered included the first author, year of publication, sample size, participant demographics, length of the follow-up period, intervention and control measures, and inclusion indications. RCTs comparing dietary supplements to placebo with the pain and function subscales of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) among patients with osteoarthritis were included. The optimal dietary supplement was identified based on the total ranking by summing the surface under the cumulative ranking curve (SUCRA) of these two scores. Furthermore, the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to confirm the quality of the evidence. RESULTS: Overall, 23 studies covering 21 dietary supplements and involving 2455 participants met the inclusion criteria. In the WOMAC pain score, the SUCRA of passion fruit peel extract was 91% (mean difference [MD]: -9.2; 95% confidence interval [CI]: [-16.0, -2.3]), followed by methylsulfonylmethane (89%), undenatured type II collagen (87%), collagen (84%), and Lanconone (82%). The SUCRA (99%) of passion fruit peel extract (MD: -41.0; 95% CI: [-66.0, -16.0]) ranked first in terms of the WOMAC function score, followed by Lanconone (95%), collagen (86%), ParActin (84%), and Lactobacillus casei strain Shirota (83%). The top three total rankings are passion fruit peel extract (95.0%), Lanconone (88.5%), and collagen (85.0%). However, the GRADE revealed low evidence quality. CONCLUSION Passion fruit peel extract was the best supplement for improving WOMAC pain and function scores in patients with osteoarthritis, followed by Lanconone and collagen. However, further large-scale, well designed RCTs are required to substantiate these promising findings. Please cite this article as: Chen CS, Wen L, Yang F, Deng YC, Ji JH, Chen RJ, Chen Z, Chen G, Gu JY. Effects of dietary supplements on patients with osteoarthritis: A systematic review and network meta-analysis. J Integr Med. 2025; 23(4): 357-369.
Humans ; Dietary Supplements ; Osteoarthritis/drug therapy* ; Randomized Controlled Trials as Topic

Acupuncture is an ancient treatment method used in traditional Chinese medicine and has been popularized worldwide. Over the past decade, there has been an increase in the amount of acupuncture research, mostly comprised of randomized controlled trials (RCTs) that aimed to answer the question on the efficacy of acupuncture. However, poor methodology and low replicability in these acupuncture RCTs have resulted in uncertainty about the efficacy of acupuncture. In this review, current advancements and challenges in acupuncture RCTs, regarding the methodological aspects of randomization, blinding, sham acupuncture and quality of reporting, were discussed. While there have been advancements in various aspects, current acupuncture RCTs still face pressing issues such as inadequate randomization and blinding, unviable sham acupuncture controls, and poor reporting quality. Given these limitations, this review seeks to identify the methodological problems that are responsible for these problems and to suggest solutions that could help to overcome them so as to improve the quality of future studies evaluating the efficacy of acupuncture. Please cite this article as: Seetoh WS, Lim RQR, Xu RB, Sun MX, Zhang P, Wang MN. Advancements and challenges of acupuncture randomized controlled trials. J Integr Med. 2025; 23(4): 333-343.
Acupuncture Therapy ; Humans ; Randomized Controlled Trials as Topic/methods* ; Research Design

BACKGROUND: Acupuncture therapy provides a complementary and alternative approach to treating major depressive disorder (MDD), but its efficacy and safety have still not been comprehensively assessed. Recently published systematic reviews remain confusing and inconclusive. OBJECTIVE: This systematic review evaluated the efficacy and safety of acupuncture therapy alone or combined with antidepressants for adult patients with mild and moderate MDD. SEARCH STRATEGY: Chinese Biomedical Literature Database, China National Knowledge Infrastructure Database, Wanfang Database, Chinese Science and Technology Journal Database, PubMed, Embase, and Cochrane Library were searched from their inceptions to March 2025. INCLUSION CRITERIA: Randomized controlled trials that compared acupuncture therapy with antidepressants, or acupuncture therapy plus antidepressants with acupuncture therapy or antidepressants for adult patients with mild and moderate MDD were included. DATA EXTRACTION AND ANALYSIS: Five reviewers independently extracted data from original literature using a standardized form, and the data were verified by two reviewers to ensure accuracy. Statistical meta-analyses, publication bias analyses, and subgroup analyses were performed by using Review Manager 5.3 software. The Grading of Recommendations Assessment, Development, and Evaluation approach was used to assess the certainty of the evidence. RESULTS: A total of 60 eligible studies including 4675 participants were included. Low-certainty evidence showed that compared with antidepressants, acupuncture therapy (standardized mean difference [SMD] = -0.57; 95% confidence interval [CI] = [-0.87, -0.27]; I² = 86%; P = 0.006) or acupuncture therapy plus antidepressants (SMD = -1.00; 95% CI = [-1.18, -0.81]; I² = 77%; P < 0.00001) may reduce the severity of depression at the end of treatment. Low-certainty evidence indicated that compared with acupuncture therapy alone, acupuncture therapy plus antidepressants slightly reduced the severity of depression at the end of treatment (SMD = -0.38; 95% CI = [-0.61, -0.14]; I² = 18%; P = 0.002). Similar results were also found for acupuncture's relief of insomnia. The reported adverse effects of acupuncture therapy were mild and transient. For most of the subgroup analyses, acupuncture type, scale type, and the course of treatment did not show a significant relative effect. CONCLUSION Acupuncture therapy may provide antidepressant effects and relieve insomnia with mild adverse effects for adult patients with mild and moderate MDD. But the certainty of evidence was very low. More high-quality, well designed, large-scale studies with long-term follow-up are needed in the future. Please cite this article as: Kuang HJ, Yang HS, Feng YX, Tang H, Fan Q, Xu YQ, Cui S, Musil R, Luxenburger H, Zhang YX, Zhao H, Zhang YQ. Efficacy and safety of acupuncture therapies for adult patients with mild and moderate major depressive disorder: A systematic review and meta-analysis. J Integr Med. 2025; 23(5):471-491.
Humans ; Acupuncture Therapy/methods* ; Depressive Disorder, Major/therapy* ; Adult ; Antidepressive Agents/therapeutic use* ; Treatment Outcome ; Randomized Controlled Trials as Topic

BACKGROUND: The use of inserted sham acupuncture as a placebo in randomized controlled trials (RCTs) is controversial, because it may produce specific effects that cause an underestimation of the effect of acupuncture treatment. OBJECTIVE: This systematic survey investigates the magnitude of insert-specific effects of sham acupuncture and whether they affect the estimation of acupuncture treatment effects. SEARCH STRATEGY: PubMed, Embase and Cochrane Central Register of Controlled Trials were searched to identify acupuncture RCTs from their inception until December 2022. INCLUSION CRITERIA: RCTs that evaluated the effects of acupuncture compared to sham acupuncture and no treatment. DATA EXTRACTION AND ANALYSIS: The total effect measured for an acupuncture treatment group in RCTs were divided into three components, including the natural history and/or regression to the mean effect (controlled for no-treatment group), the placebo effect, and the specific effect of acupuncture. The first two constituted the contextual effect of acupuncture, which is mimicked by a sham acupuncture treatment group. The proportion of acupuncture total effect size was considered to be 1. The proportion of natural history and/or regression to the mean effect (PNE) and proportional contextual effect (PCE) of included RCTs were pooled using meta-analyses with a random-effect model. The proportion of acupuncture placebo effect was the difference between PCE and PNE in RCTs with non-inserted sham acupuncture. The proportion of insert-specific effect of sham acupuncture (PIES) was obtained by subtracting the proportion of acupuncture placebo effect and PNE from PCE in RCTs with inserted sham acupuncture. The impact of PIES on the estimation of acupuncture's treatment effect was evaluated by quantifying the percentage of RCTs that the effect of outcome changed from no statistical difference to statistical difference after removing PIES in the included studies, and the impact of PIES was externally validated in other acupuncture RCTs with an inserted sham acupuncture group that were not used to calculate PIES. RESULTS: This analysis included 32 studies with 5492 patients. The overall PNE was 0.335 (95% confidence interval [CI], 0.255-0.415) and the PCE of acupuncture was 0.639 (95% CI, 0.567-0.710) of acupuncture's total effect. The proportional contribution of the placebo effect to acupuncture's total effect was 0.191, and the PIES was 0.189. When we modeled the exclusion of the insert-specific effect of sham acupuncture, the acupuncture treatment effect changed from no difference to a significant difference in 45.45% of the included RCTs, and in 40.91% of the external validated RCTs. CONCLUSION The insert-specific effect of sham acupuncture in RCTs represents 18.90% of acupuncture's total effect and significantly affects the evaluation of the acupuncture treatment effect. More than 40% of RCTs that used inserted sham acupuncture would draw different conclusions if the PIES had been controlled for. Considering the impact of the insert-specific effect of sham acupuncture, caution should be taken when using inserted sham acupuncture placebos in RCTs. Please cite this article as: Luo XC, Liu JL, Yao MH, Chen YM, Fan AY, Liang FR, Zhao JP, Zhao L, Zhou X, Zhong XY, Yang JH, Li B, Zhang Y, Sun X, Li L. Specific effect of inserted sham acupuncture and its impact on the estimation of acupuncture treatment effect in randomized controlled trials: A systematic survey. J Integr Med. 2025; 23(6):630-640.
Acupuncture Therapy/methods* ; Humans ; Randomized Controlled Trials as Topic ; Placebo Effect ; Placebos ; Treatment Outcome