Wright Kath, Golder Su, Rodriguez-Lopez Rocio
Centre for Reviews and Dissemination, A/B Block, Alcuin College, University of York, York YO10 5DD, UK.
BMC Med Res Methodol. 2014 Jun 3;14:73. doi: 10.1186/1471-2288-14-73.
The value of citation searches as part of the systematic review process is currently unknown. While the major guides to conducting systematic reviews state that citation searching should be carried out in addition to searching bibliographic databases there are still few studies in the literature that support this view. Rather than using a predefined search strategy to retrieve studies, citation searching uses known relevant papers to identify further papers.
We describe a case study about the effectiveness of using the citation sources Google Scholar, Scopus, Web of Science and OVIDSP MEDLINE to identify records for inclusion in a systematic review.We used the 40 included studies identified by traditional database searches from one systematic review of interventions for multiple risk behaviours. We searched for each of the included studies in the four citation sources to retrieve the details of all papers that have cited these studies.We carried out two analyses; the first was to examine the overlap between the four citation sources to identify which citation tool was the most useful; the second was to investigate whether the citation searches identified any relevant records in addition to those retrieved by the original database searches.
The highest number of citations was retrieved from Google Scholar (1680), followed by Scopus (1173), then Web of Science (1095) and lastly OVIDSP (213). To retrieve all the records identified by the citation tracking searching all four resources was required. Google Scholar identified the highest number of unique citations.The citation tracking identified 9 studies that met the review's inclusion criteria. Eight of these had already been identified by the traditional databases searches and identified in the screening process while the ninth was not available in any of the databases when the original searches were carried out. It would, however, have been identified by two of the database search strategies if searches had been carried out later.
Based on the results from this investigation, citation searching as a supplementary search method for systematic reviews may not be the best use of valuable time and resources. It would be useful to verify these findings in other reviews.
作为系统评价过程一部分的引文检索的价值目前尚不清楚。虽然进行系统评价的主要指南指出，除了检索书目数据库外，还应进行引文检索，但文献中仍很少有研究支持这一观点。引文检索不是使用预定义的检索策略来检索研究，而是利用已知的相关论文来识别更多论文。
我们描述了一个案例研究，该研究关于使用谷歌学术、Scopus、科学网和OVIDSP MEDLINE等引文来源来识别纳入系统评价的记录的有效性。我们使用了从一项针对多种风险行为干预措施的系统评价中通过传统数据库检索确定的40项纳入研究。我们在四个引文来源中搜索每项纳入研究，以检索所有引用这些研究的论文的详细信息。我们进行了两项分析；第一项是检查四个引文来源之间的重叠情况，以确定哪种引文工具最有用；第二项是调查引文检索是否除了原始数据库检索所获取的记录之外还识别出了任何相关记录。
从谷歌学术检索到的引用次数最多（1680次），其次是Scopus（1173次），然后是科学网（1095次），最后是OVIDSP（213次）。要检索到引文追踪所识别的所有记录，需要使用所有这四个资源。谷歌学术识别出的唯一引用次数最多。引文追踪识别出9项符合该评价纳入标准的研究。其中8项已经在传统数据库检索中被识别，并在筛选过程中被确定，而第9项在进行原始检索时在任何数据库中都未找到。然而，如果稍后进行检索，它会被两种数据库检索策略识别出来。
基于本次调查结果，作为系统评价的补充检索方法，引文检索可能并非对宝贵时间和资源的最佳利用方式。在其他评价中验证这些结果将是有益的。
