Non-randomised studies of the effects of interventions (NRSI) are critical to many areas of healthcare evaluation. Designs of NRSI that can be used to evaluate the effects of interventions include observational studies such as cohort studies and case-control studies in which intervention groups are allocated during the course of usual treatment decisions, and quasi-randomised studies in which the method of allocation falls short of full randomisation.  The ROBINS-I tool (“Risk Of Bias In Non-randomised Studies - of Interventions”) is concerned with evaluating risk of bias in estimates of the effectiveness or safety (benefit or harm) of an intervention from studies that did not use randomisation to allocate interventions. 

Cochrane Scientific Committee recommendation (Full statement, July 2017):
ROBINS-I is the preferred tool to be used in Cochrane Reviews for non-randomized studies of interventions, although it is not mandatory, and will require author teams to have sufficient knowledge and experience to apply the tool. An alternative option is the Newcastle-Ottawa Scale. Please await further announcements on guidance and support to implement this tool.

Key resources: