Article type
Year
Abstract
Background:
Relying on Cochrane Reviews (CR) is recognized as an efficient way of making evidence-based health decisions.
Objectives:
To explore how often CRs are available for clinical questions; if they outperform other systematic reviews (SRs); and if they include all the relevant evidence.
Methods:
In the context of clinical meetings of one public and one private hospital in Chile, we selected one condition per month to be discussed. A team generated a list of clinical questions or hot topics, and the staff selected 2-5 questions that were worth reviewing during the meetings. We prepared matrices of evidence in Epistemonikos (a table comparing all of the reviews and all of the primary studies for a question). Epistemonikos searches for SRs across 20 databases. We measured the number of questions answered by any SR; number of questions answered by a CR; number of times a CR was the newer/more complete; and if the CR included all the relevant trials identified in the matrix.
Results:
Thirty-two clinical questions were reviewed during an 8-month period. The average of SR per question was 4.4 (0 to 19). For 25/32 (78%) we identified at least one SR, but only 12/32 (38%) were answered by a CR. From 12 questions for which a CR was available, in 9/12 (75%) Cochrane was the more complete, and in 8/12 (66%) it was the newest. We checked the CR against all the relevant primary studies identified in the matrix, and went to the full text to evaluate if the authors had excluded or missed the studies that other reviews had included. Only 5 CRs had found all the relevant evidence.
Conclusions:
A substantial proportion of questions can be answered with SRs. However, non-Cochrane reviews (NCRs) had much better coverage than CRs. When there were both CRs and NCRs, CRs were more complete and newer than NCRs, but there is still room for improvement. Only one in every six questions was answered by a Cochrane Review including all of the relevant evidence. Our results emphasize the need for producing reviews covering the more relevant topics, and the challenges for Cochrane to be the more reliable source of evidence.
Relying on Cochrane Reviews (CR) is recognized as an efficient way of making evidence-based health decisions.
Objectives:
To explore how often CRs are available for clinical questions; if they outperform other systematic reviews (SRs); and if they include all the relevant evidence.
Methods:
In the context of clinical meetings of one public and one private hospital in Chile, we selected one condition per month to be discussed. A team generated a list of clinical questions or hot topics, and the staff selected 2-5 questions that were worth reviewing during the meetings. We prepared matrices of evidence in Epistemonikos (a table comparing all of the reviews and all of the primary studies for a question). Epistemonikos searches for SRs across 20 databases. We measured the number of questions answered by any SR; number of questions answered by a CR; number of times a CR was the newer/more complete; and if the CR included all the relevant trials identified in the matrix.
Results:
Thirty-two clinical questions were reviewed during an 8-month period. The average of SR per question was 4.4 (0 to 19). For 25/32 (78%) we identified at least one SR, but only 12/32 (38%) were answered by a CR. From 12 questions for which a CR was available, in 9/12 (75%) Cochrane was the more complete, and in 8/12 (66%) it was the newest. We checked the CR against all the relevant primary studies identified in the matrix, and went to the full text to evaluate if the authors had excluded or missed the studies that other reviews had included. Only 5 CRs had found all the relevant evidence.
Conclusions:
A substantial proportion of questions can be answered with SRs. However, non-Cochrane reviews (NCRs) had much better coverage than CRs. When there were both CRs and NCRs, CRs were more complete and newer than NCRs, but there is still room for improvement. Only one in every six questions was answered by a Cochrane Review including all of the relevant evidence. Our results emphasize the need for producing reviews covering the more relevant topics, and the challenges for Cochrane to be the more reliable source of evidence.