Internal validity of non-randomised studies (NRS) on interventions Guideline Final Jul 2015

This website was produced under the Third EU Health Programme through a service contract with the European Health and Digital Executive Agency (HaDEA) acting under the mandate from the European Commission. The information and views set out in this website are those of the author(s) and do not necessarily reflect the official opinion of the Commission/Executive Agency. The Commission/Executive Agency do not guarantee the accuracy of the data included in this website. Neither the Commission/Executive Agency nor any person acting on the Commission’s/Executive Agency’s behalf may be held responsible for the use which may be made of the information contained therein.