Novel approaches to conducting overviews of reviews: Lessons from four overviews of health systems interventions

ID: 

19059

Session: 

Long oral session 8: Methods for overviews

Date: 

Wednesday 13 September 2017 - 16:00 to 17:30

Location: 

Meeting Room 1.63

All authors in correct order:

Lewin S1, Oxman A2, Ciapponi A3, Herrera C4, Opiyo N5, Pantoja T6, Paulsen E7, Rada G8, Wiysonge C9
1 Cochrane EPOC, Cochrane Norway, Norwegian Institute of Public Health; and South African Medical Research Council, Norway
2 Cochrane EPOC, Cochrane Norway, Norwegian Institute of Public Health, Norway
3 Argentine Cochrane Centre, Institute for Clinical Effectiveness and Health Policy (IECS), Argentina
4 Department of Public Health and Evidence Based Health Care Program, Pontificia Universidad Católica de Chile, Chile
5 Cochrane Editorial Unit, Cochrane, Norway
6 Evidence Based Health Care Program and Department of Family Medicine, Pontificia Universidad Católica de Chile, Chile
7 Cochrane EPOC, Norwegian Institute of Public Health, Norway
8 Evidence Based Health Care Program, Pontificia Universidad Católica de Chile, Chile
9 Cochrane South Africa, South African Medical Research Council, South Africa
Presenting author and contact person

Presenting author:

Simon Lewin

Contact person:

Simon Lewin
Agustín Ciapponi
Charles Wiysonge
Gabriel Rada
Abstract text
Background: Overviews of the findings of systematic reviews of health systems interventions can help policy makers and other stakeholders to identify strategies for strengthening health systems. Methods for conducting such overviews are still evolving.

Objectives: 1) To examine the strengths and weaknesses of the methods used for four overviews of reviews of health systems reviews relevant to low income countries; and. 2) To discuss the methodological lessons from undertaking these overviews.

Methods: The overview methods were as follows: we searched PDQ Evidence – a database of evidence for health systems decisions – for relevant reviews and included well-conducted reviews published between 2005 and 2016 of studies that assessed the effects of governance, financial and delivery arrangements and implementation strategies. We excluded reviews that had limitations that were important enough that the findings of the review were not reliable. Two overview authors independently screened reviews, extracted data and assessed the certainty of evidence using GRADE. We prepared SUPPORT Summaries for eligible reviews, including key messages, summary of findings tables and assessments of relevance of findings to low income countries. We then reflected on the strengths and weaknesses of the methods used and identified lessons learned.

Results: The strengths of our methods included: 1) a ‘layered’ approach to evidence presentation; 2) multiple checks through the review process for the reliability and applicability of reviews; and, 3) use of a well-tested format (SUPPORT summaries) for presenting review findings. Key limitations: 1) the process was very time and resource-intensive; and, 2) the preparation of summaries is a highly specialised task. Challenges included multiple, overlapping reviews on many topics; few data on resource use, adverse effects and equity impacts in reviews; and the wider challenge of summarising and presenting complex information on health systems.

Conclusions:Producing overviews would be facilitated by the wider use of summaries of findings tables and user-friendly formats in reviews of health systems interventions.