title: Effect of Chinese patent medicine Si-Mo-Tang oral liquid for functional dyspepsia: A systematic review and meta-analysis of randomized controlled trials.
abstract: BACKGROUND
  Si-Mo-Tang oral liquid (SMT) has been widely used to treat functional dyspepsia (FD), but the effectiveness is still controversial. A systematic review and meta-analysis of randomized controlled trials (RCTs) were performed to assess the efficacy and adverse effects of SMT for FD.
  
  
  METHODS
  Investigators searched for articles with publication dates to June 21, 2016, from 9 English and Chinese electronic databases. Comparisons were SMT alone or SMT in combination with western medicine as experimental intervention, and western medicine or placebo as the control. We used the Cochrane collaboration tool for assessing risk of bias to evaluate methodologies. Data were synthesized with RevMan 5.3 software. (PROSPERO Registration #CRD42016042003).
  
  
  RESULTS
  Twenty-seven RCTs were included in the review, involving 2,713 participants: 1,383 subjects were in the experimental group and 1,330 in the control group. SMT showed a significant improvement in clinical efficacy (RR 1.14; 95% CI 1.09, 1.20; P<0.00001), but the heterogeneity was also significant (P = 0.0002, I2 = 56%). Because of the different interventions in the 2 groups, we performed subgroup and sensitivity analyses to investigate potential sources of heterogeneity. The heterogeneity was smaller after subgroup analysis and the exclusion of a study by Zhu from 2009. The corresponding pooled RR has no obvious change (RR 1.17; 95% CI 1.13, 1.21; P<0.00001). Subgroup analysis by age and drugs administered in control interventions between SMT and western medicine also showed improvement in the efficacy rate. But a data synthesis that excluded high risk of bias in the blinding of participants and personnel showed no significant difference (RR 1.14; 95% CI 0.97, 1.35; P = 0.12). Three studies measured gastric emptying. Two of these studies reported no significant difference between the experimental and control groups, while 1 study showed that SMT reduced the time of gastric emptying. The relapse rate and adverse effects had no difference between 2 groups.
  
  
  CONCLUSIONS
  This meta-analysis suggests that SMT is an effective and safe therapy option for patients with FD. However, because of the high clinical heterogeneity, poor quality, high risk of bias and small sample size of some included studies, further standardized large-scale and strictly designed studies are needed.
authors.affiliation: The First College of Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China.
authors.forename: Yunxia
authors.initials: Y
authors.lastname: Hu
authors.affiliation: The First College of Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Bai
authors.affiliation: Department of Respiration, Zhenjiang Hospital of Traditional Chinese Medicine, Zhenjiang, Jiangsu, China.
authors.forename: Zhiyun
authors.initials: Z
authors.lastname: Hua
authors.affiliation: Department of Intensive Care Unit, Liyang Hospital of Traditional Chinese Medicine, Changzhou, Jiangsu, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.affiliation: Jockey School of Public Health, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Huahui
authors.initials: H
authors.lastname: Yang
authors.affiliation: Department of Obstetrics and Gynecology, Zhejiang Hospital of Traditional Chinese Medicine, Hangzhou, Zhejiang, China.
authors.forename: Wenjun
authors.initials: W
authors.lastname: Chen
authors.affiliation: The First College of Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China.
authors.forename: Junwei
authors.initials: J
authors.lastname: Xu
authors.affiliation: The First College of Clinical Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, China.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zhao
mesh_terms: D000284:Administration, Oral; D016208:Databases, Factual; D004365:Drugs, Chinese Herbal / Q000627:therapeutic use*; D004415:Dyspepsia / Q000188:drug therapy*; D006801:Humans; D008516:Medicine, Chinese Traditional; D016032:Randomized Controlled Trials as Topic; D012306:Risk; D016896:Treatment Outcome
chemical_list: D004365:Drugs, Chinese Herbal