Appraisal of: Hopewell S, Clarke M, Lefebvre C, Scherer R. Handsearching versus electronic searching to identify reports of randomized trials. Cochrane Database Syst Rev. 2007; (2): MR000001.

Short description: 

Aim of the Cochrane review was to compare the technique of handsearching with electronic searching to identify RCT.

Thirty-four studies were included. Handsearching identified between 92% to 100% of the total number of reports of randomized trials found in the various comparisons in this review. Searching MEDLINE retrieved 55%, EMBASE 49% and PyscINFO 67%. The retrieval rate of the electronic database varied depending on the complexity of the search. The Cochrane Highly Sensitive Search Strategy (HSSS) identified 80% of the total number of reports of randomized trials.

Conclusion of the authors is, that hand searching has a valuable role in identifying reports of RCT for inclusion in SR of health care interventions.

Particularly important in identifying trials reported as abstracts, letters and those published in languages other than English.

Limitations stated by the author(s): 

In this review, no attempts were made to assess the importance of the trials missed by either handsearching or electronic searching. There is evidence to suggest that only around half of all trials reported as abstracts are subsequently published in full and that published trials may show a larger treatment effect than ’grey’ trials (for example those published as conference abstracts). Further research is needed to assess the importance of those trials missed by either method of searching.

Limitations stated by the reviewer(s): 
Main problem is, that the review is outdated. The last search was in 2002. Handsearch was mainly compared to “old” 3 phase Highly Sensitive Search Strategy filter.
Study Type: 
Review