Background section at Cochrane reviews: is it supported by systematic reviews?

Session: 

Oral session: Knowledge translation and communicating evidence (8)

Date: 

Tuesday 18 September 2018 - 15:10 to 15:20

Location: 

Sidlaw Auditorium

All authors in correct order:

Glujovsky D1, Bardach A1, Comande D1, Ciapponi A1
1 Institute for Clinical Effectiveness and Health Policy (IECS-CONICET), Argentina
Presenting author and contact person

Presenting author:

Demián Glujovsky

Contact person:

Demián Glujovsky
Agustín Ciapponi
Abstract text
Background: Usually, any Cochrane systematic review is considered as an important piece of research by readers. Although the Methods and Results are based on a systematic approach, the introduction might not be. Some readers (patients, other researchers and healthcare workers) retrieve information directly from the Background as if it were strong evidence and as if authors had done a comprehensive search, just because it comes from a Cochrane Review. However, we should note that, if evidence supporting this section is not of high quality, the information given is not either.

Objectives: To analyze if the 'Description of the condition' of the Background section is based on systematic reviews, and to evaluate if there were systematic reviews available that were not used in this section.

Methods: We analyzed all the intervention Cochrane Reviews published in Nov-Dec 2017. We excluded updates. We retrieved the references from the 'Background, Description of the condition' section. We ran the same search strategy in PubMed as authors used in the systematic review, and added a filter for systematic reviews and another one for burden of disease (see Box 1). We analyzed whether the retrieved studies were systematic reviews that could support the information given in that section, and if they were different from the references found by authors.

Results: At the time of submission, 12 reviews were analyzed. Full information will be given at the Colloquium. We found that in seven (58%) reviews, no systematic reviews were used to support the information given to describe the condition. When checking the studies retrieved by our search strategy, we identified systematic reviews that could have been used in 43% of those that did not use any. Five (42%) used systematic reviews, but were not comprehensive, as in 60% we found more systematic reviews that could have been used too.

Conclusions: A large proportion of references in the Background were not systematic reviews. Authors should make greater efforts to retrieve the best evidence for this section. Readers should appraise this information critically, since sometimes it is not based on high-quality evidence. This study wants to alert patients and consumers about this potential issue when reading Cochrane Reviews.

Patient or healthcare consumer involvement: Healthcare consumers participated as authors.

Relevance to patients and consumers: 

Any Cochrane systematic review is usually considered as an important piece of research by patients and consumers. Although the Methods and Results are based on a systematic approach, introduction could not. Some readers retrieve information directly from background as if it were strong evidence because it comes from a Cochrane review. However, we should note that, if evidence supporting this section is not high quality, the information given is not either. This study wants to alert patients and consumers from this potential issue when reading a Cochrane review.