解决元分析和随后的大型受控试验之间的差异.
1Division of Epidemiology, Statistics, and Prevention Research, National Institute of Child Health and Development, Bethesda, MD 20892-7510, USA. DerSimonian@nih.gov
JAMA
|October 12, 1999
概括
补充可以预防健康的高风险女性的孕前症,但不是低风险人群. 需要进一步的研究来确认高风险群体的疗效. 孕前的预防仍然是研究的一个领域.
科学领域:
- 产科和妇科 产科和妇科
- 营养科学 营养科学
- 临床流行病学临床流行病学
背景情况:
- 一项元分析表明,补充可以有效地预防孕前.
- 美国国家卫生研究院 (NIH) 进行的预防产前的 (CPEP) 试验没有发现健康的无孕妇女的风险降低.
- 研究之间存在差异,因此需要进一步调查在孕前预防中的作用.
研究的目的:
- 为了协调元分析和CPEP试验之间的相互矛盾的发现.
- 评估效果异质性对研究差异的影响.
- 评估补充的有效性,以预防产前.
主要方法:
- 1997年7月10日之前发表的英语文章的系统文献审查.
- 包括报告关于孕前和补充的数据的试验.
- 对14项试验的分析,按安慰剂控制组和风险人群分层 (高风险与低风险).
主要成果:
- 在各个试验中观察到实质性的异质性 (P = .001).
- 在与低风险人群的安慰剂对照试验中,没有显著的益处 (RR,0.79;P = .30),与CPEP试验结果保持一致.
- 在健康的高风险人群中,表明有很大的益处 (RR,0.19;P = .001),尽管由于样本小 (n=225) 和数据不一致,结果是模两可的.
结论:
- 补充剂在健康高风险人群中预防孕前的有效性需要进一步研究.
- 对于具有显著异质性的元分析,单一的总结措施是不够的.
- 识别共变量以减少异质性对于优化治疗策略至关重要.
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