Classifying non-randomised studies (NRS) and assessing the risk of bias for a systematic review

Topic category Investigating bias
Date and Location
Monday 1 October 2012 - 13:30 - 15:00
Methods Group
Methods Group: 
Non-Randomised Studies Methods Group
Contact persons and facilitators
Contact person Affiliation Country
Barnaby Reeves (Contact this person) Non-Randomised Studies Methods Group United Kingdom
Facilitator Affiliation Country
Beverley Shea CIETcanada Canada
Other contributors
First nameLast nameAffiliation and Country
First name: 
Last name: 
Affiliation and Country: 
Univeristy of Ottawa, Canada
Target audience
Target audience: 
Review authors and editors considering whether or not to include non-randomised studies (NRS) in Cochrane systematic reviews
Is your workshop restricted to a specific audience or open to all Colloquium participants?: 
Level of knowledge required: 
Type of workshop
Type of workshop: 
Abstract text
The workshop aims to improve awareness of the key issues when including non-randomised studies (NRS) in systematic reviews of effectiveness.

This workshop is aimed at review authors and editors who are considering whether or not to include NRS in reviews to estimate the benefits of an intervention. This situation may arise when there are no RCTs, only poor RCTs or very few small RCTs, but where the question addressed by the review is a priority. Evaluations of public health, practitioner-dependent or device-based interventions may have these limitations. Participants will mainly work in small groups to apply tools developed by the NRSMG to a single NRS. First, participants will classify the NRS with respect to study features (likely to be relevant to setting review eligibility criteria) that the NRSMG recommends extracting from primary studies. Second, participants will assess the risk of bias in the NRS using an extended risk-of-bias tool. The implications of varying amounts and quality of information from primary NRS for systematic reviews of NRS will be discussed. Varying amounts and quality of information is also the norm for systematic reviews of RCTs, so the discussion will contrast the implications for systematic reviews of NRS and RCTs.