Manchikanti Laxmaiah, Datta Sukdeb, Smith Howard S, Hirsch Joshua A
Pain Management Center of Paducah, Paducah, KY, USA.
Pain Physician. 2009 Sep-Oct;12(5):819-50.
Observational studies provide an important source of information when randomized controlled trials (RCTs) cannot or should not be undertaken, provided that the data are analyzed and interpreted with special attention to bias. Evidence-based medicine (EBM) stresses the examination of evidence from clinical research and describes it as a shift in medical paradigm, in contrast to intuition, unsystematic clinical experience, and pathophysiologic rationale. While the importance of randomized trials has been created by the concept of the hierarchy of evidence in guiding therapy, much of the medical research is observational. The reporting of observational research is often not detailed and clear enough with insufficient quality and poor reporting, which hampers the assessment of strengths and weaknesses of the study and the generalizability of the mixed results. Thus, in recent years, progress and innovations in health care are measured by systematic reviews and meta-analyses. A systematic review is defined as, "the application of scientific strategies that limit bias by the systematic assembly, clinical appraisal, and synthesis of all relevant studies on a specific topic." Meta-analysis usually is the final step in a systematic review. Systematic reviews and meta-analyses are labor intensive, requiring expertise in both the subject matter and review methodology, and also must follow the rules of EBM which suggests that a formal set of rules must complement medical training and common sense for clinicians to integrate the results of clinical research effectively. While expertise in the review methods is important, the expertise in the subject matter and technical components is also crucial. Even though, systematic reviews and meta-analyses, specifically of RCTs, have exploded, the quality of the systematic reviews is highly variable and consequently, the opinions reached of the same studies are quite divergent. Numerous deficiencies have been described in methodologic assessment of the quality of the individual articles. Consequently, observational studies can provide an important complementary source of information, provided that the data are analyzed and interpreted in the context of confounding bias to which they are prone. Appropriate systematic reviews of observational studies, in conjunction with RCTs, may provide the basis for elimination of a dangerous discrepancy between the experts and the evidence. Steps in conducting systematic reviews of observational studies include planning, conducting, reporting, and disseminating the results. MOOSE, or Meta-analysis of Observational Studies in Epidemiology, a proposal for reporting contains specifications including background, search strategy, methods, results, discussion, and conclusion. Use of the MOOSE checklist should improve the usefulness of meta-analysis for authors, reviewers, editors, readers, and decision-makers. This manuscript describes systematic reviews and meta-analyses of observational studies. Authors frequently utilize RCTs and observational studies in one systematic review; thus, they should also follow the reporting standards of the Quality of Reporting of Meta-analysis (QUOROM) statement, which also provides a checklist. A combined approach of QUOROM and MOOSE will improve reporting of systematic reviews and lead to progress and innovations in health care.
当无法或不应进行随机对照试验（RCT）时，观察性研究可提供重要的信息来源，前提是对数据进行分析和解释时要特别注意偏差。循证医学（EBM）强调对临床研究证据的审查，并将其描述为医学范式的转变，与直觉、非系统的临床经验和病理生理原理形成对比。虽然随机试验的重要性是由证据等级概念在指导治疗中确立的，但许多医学研究都是观察性的。观察性研究的报告往往不够详细和清晰，质量不足且报告不佳，这妨碍了对研究优缺点的评估以及混合结果的可推广性。因此，近年来，医疗保健领域的进展和创新是通过系统评价和荟萃分析来衡量的。系统评价被定义为“应用科学策略，通过系统收集、临床评估和综合特定主题的所有相关研究来限制偏差”。荟萃分析通常是系统评价的最后一步。系统评价和荟萃分析工作量大，需要在主题和评价方法方面都具备专业知识，并且还必须遵循循证医学的规则，这表明一套正式的规则必须补充医学培训和临床医生的常识，以便他们有效地整合临床研究结果。虽然评价方法方面的专业知识很重要，但主题和技术组成部分方面的专业知识也至关重要。尽管系统评价和荟萃分析，特别是对随机对照试验的分析大量涌现，但系统评价的质量差异很大，因此，对同一研究得出的观点差异也很大。在对单个文章质量的方法学评估中已经描述了许多不足之处。因此，观察性研究可以提供重要的补充信息来源，前提是在其容易出现的混杂偏差背景下对数据进行分析和解释。对观察性研究进行适当的系统评价，并结合随机对照试验，可能为消除专家与证据之间的危险差异提供基础。对观察性研究进行系统评价的步骤包括规划、开展、报告和传播结果。MOOSE，即流行病学观察性研究的荟萃分析，一份报告提案包含了包括背景、检索策略、方法、结果、讨论和结论等方面的规范。使用MOOSE清单应能提高荟萃分析对作者、审稿人、编辑、读者和决策者的有用性。本手稿描述了观察性研究的系统评价和荟萃分析。作者在一项系统评价中经常同时使用随机对照试验和观察性研究；因此，他们还应遵循荟萃分析报告质量（QUOROM）声明的报告标准，该声明也提供了一份清单。QUOROM和MOOSE的联合方法将改善系统评价的报告，并导致医疗保健领域的进展和创新。
