The placebo effect in irritable bowel syndrome trials: a meta-analysis
The placebo effect in irritable bowel syndrome trials: a meta-analysis
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DOI：
10.1111/j.1365-2982.2005.00650.x
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发表时间：
2005-06-01
影响因子：
3.5
通讯作者：
Lembo, AJ
中科院分区：
文献类型：
--
作者：
Patel, SM;Stason, WB;Lembo, AJ
背景：尽管肠易激综合征 (IBS) 患者的随机安慰剂对照试验 (RCT) 中安慰剂反应率明显较高，但我们对这种反应的变异性和预测因素知之甚少。目的：描述 IBS 临床试验中安慰剂组的反应程度，并确定哪些因素可预测安慰剂反应的变异性。方法：我们对 20 名或更多接受治疗的 IBS 患者已发表的英文 RCT 进行了荟萃分析至少 2 周。该分析仅限于评估总体反应（整体症状改善）的研究。被视为潜在安慰剂修饰因素的变量包括研究设计、研究持续时间、磨合期的使用、Jadad 评分、进入标准、就诊次数、就诊次数/研究持续时间、诊断测试的使用、性别、年龄和所研究药物的类型。 结果：45 项安慰剂对照随机对照试验符合纳入标准。安慰剂反应范围为 16.0% 至 71.4%，人群加权平均值为 40.2%，95% CI (35.9-44.4)。与较低安慰剂反应率的显着关联是满足罗马研究标准 (P = 0.049) 和增加就诊次数 (P = 0.026)。结论：衡量全球结果的 IBS 临床试验中安慰剂效应变化很大。进入标准和就诊次数是安慰剂反应的重要预测因素。更严格的准入标准和增加的就诊次数似乎会独立降低安慰剂反应。
Background: Despite the apparent high placebo response rate in 'randomized placebo-con trolled trials (RCT) of patients with irritable bowel syndrome (IBS), little is known about the variability and predictors of this response.Objectives: To describe the magnitude of response in placebo arms of IBS clinical trials and to identify which factors predict the variability of the placebo response.Methods: We performed a meta-analysis of published, English language, RCT with 20 or more IBS patients who were treated for at least 2 weeks. This analysis is limited to studies that assessed global response (improvement in overall symptoms). The variables considered as potential placebo modifiers were study design, study duration, use of a run-in phase, Jadad score, entry criteria, number of office visits, number of office visits/study duration, use of diagnostic testing, gender, age and type of medication studied.Findings: Forty-five placebo-con trolled RCTs met the inclusion criteria. The placebo response ranged from 16.0 to 71.4% with a population-weighted average of 40.2%, 95% CI (35.9-44.4). Significant associations with lower placebo response rates were fulfilment of the Rome criteria for study entry (P = 0.049) and an increased number of office visits (P = 0.026).Conclusions: Placebo effects in IBS clinical trials measuring a global outcome are highly variable. Entry criteria and number of office visits are significant predictors of the placebo response. More stringent entry criteria and an increased number of office visits appear to independently decrease the placebo response.