Appraisal of: "Kuper H, Nicholson A, Hemingway H. Searching for observational studies: what does citation tracking add to PubMed? A case study in depression and coronary heart disease. BMC Med Res Methodol. 2006;6: 4."
Kuper H, Nicholson A, Hemingway H. Searching for observational studies: what does citation tracking add to PubMed? A case study in depression and coronary heart disease. BMC Med Res Methodol. 2006;6: 4.
Articles investigating the role of depression in the aetiology and prognosis of coronary heart disease were sought through two methods: a) PubMed, and b) citation tracking where Science Citation Index was searched for all articles which cited ("forward citation tracking") or were cited by ("backward citation tracking") any of the articles in an index review.
50 articles that were not already included in the index review met our inclusion criteria; 11 were identified through Science Citation Index alone (7 forward, 4 backward), 8 through PubMed alone
Limitations stated by the author(s):
The present case study does not prove that citation tracking improves upon PubMed in other observational settings and the results cannot be generalised to searches for clinical trials, but we suspect that the chances of funding such bibliographic research are low.
Limitations stated by the reviewer(s):
It was analyzed only the value of citation tracking compared to a PubMed search[RW1] . It should have been stated by the authors that information retrieval for a systematic review contains several sources (e.g. Search in several databases and other information sources as searching in study registries or scanning reference lists and so on). So in my point of view it is not appropriate to make a statement on the overall value of citation tracking in conducting a systematic review. In addition, the results of forward and backward citation searching can not be analyzed separately.