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Handsearching: an old strategy in the era of the information
Garcia JM, Pardo J, Bonfill XIberoamerican Cochrane Centre
Hospital de la Santa Creu i Sant PauBarcelona-SPAIN
EAHIL/9 - 2004 Santander, SPAIN
Handsearching project
• Major activity of The Cochrane Collaboration
The Cochrane Collaboration?
• An international non-profit and independent organisation, dedicated to making up-to-date, accurate information about the effects of healthcare readily available worldwide.
Main Activities of CC
• “Preparing, maintaining and promoting the accessibility to systematic reviews of the effects of health care”
• The major product of the Collaboration is the Cochrane Database of Systematic Reviews published quarterly in The Cochrane Library
Cochrane Systematic review?
A Cochrane Review is a systematic, up-to-date summary of reliable evidence of the benefits and risks of healthcare. Cochrane Reviews are intended to help people make practical decisions.
Background (1)
• Systematic reviews (SR) need to be based on all the available evidence.
• SR of effectiveness of interventions are typically based on reports of RCTs
• Electronic databases do not always allow to identify them due to:– inadequate indexing of this type of study– Not all journals are indexed in the main
databases
Background (2)
• Iberoamerican Cochrane Centre register of clinical trials published in Spanish.
Objectives
• To identify randomised controlled trials in Spanish journals
• To register randomised controlled trials in CENTRAL in The Cochrane Library
• To increase the accessibility of randomised controlled trials published in Spanish journals
Methods (1)
• Identification of all health care journals published in Spain (“Catálogo C-17”)
• Selection of journals to be handsearched• Registration of journals on Cochrane
Collaboration’s Master List• Training handsearchers• Handsearch journal issues to identify possible
randomised controlled trials • All reports identified verified by Trial Search
Coordinator, and rejected if necessary
Methods (2)
• All controlled trials entered in a Procite® database
• Electronic records generated and submitted for inclusion in the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library
• Journals handsearched from 1948 to 2001
Characteristics of Randomised Controlled
Trials• The study compares interventions in
humans
• The study is prospective
• Two or more interventions are compared
• Random assignment of participants to interventions
Handsearcher
Copies of originals
Organise handsearching
Trials SearchCo-ordinator
IbCC
Evaluation by TSC
Accepted
Rejected
US Cochrane
Center
Sending reference database containing electronic citations of
identified trials
Register journal searches on Master List
Flow chart C LIB
Trials Search Coordinator God
TSC
My office... In heaven
- Yes, is a Trial - No, is not a Trial
All you need is trials
- Oh my god, I need a trial
Difficult access
Please, all my reports should be trials
The new generation
My god, I need found trials in my stories
…exhausted TSC
Results (I)
• Identified 643 Spanish health care journals
• 41 indexed in Medline
• 432 (67%) journals handsearched
Results (II)
• 3,548 randomised controlled trials identified
• 2,028 (57.2%) randomised controlled trials from journals not indexed in Medline
• More trials identified between 1992-1996
0
200
400
600
800
1000
1200
1400
1957-61 1962-66 1967-71 1972-76 1977-81 1982-86 1987-91 1992-96 1997-2001
Number of trial reports in each publicationyear
0
500
1000
1500
2000
2500
Medline Indexed Journals Non-Medline indexedJournals
Total number of trials in indexed in Medline journals
Versus journals not indexed in Medline
1,520
2,028
Global Results of database and handsearches
415,918 Reports of Trials
CENTRAL
• “The Cochrane Central Register of Controlled Trials”
Likely to be the best single source of published trials for inclusion in systematic reviews and meta-analyses
Egger M, Smith GD. Bias in location and selection of studies. BMJ 1998;316:61-6.
Conclusions• The handsearch has made available
controlled trials from a greater number of journals
• Handsearching has added significant results to the information from controlled trials published in Spanish journals
• Handsearching contributes to increase the available knowledge to everyone involved in evidence-based health care
Acknowledgements
- Sources of support:• BIOMED-1 Program [BMH1-CT94-1289]• BIOMED-2 Program [BMH4-CT98-3803]• FIS Project [96/1802E]• FIS Project [99/1333]• SEOM• Marató TV3• FIPSE- The authors thank all the handsearchers who
participated in this project.
