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8.16  Chapter information

Editors: Julian PT Higgins, Douglas G Altman and Jonathan AC Sterne on behalf of the Cochrane Statistical Methods Group and the Cochrane Bias Methods Group.

This chapter should be cited as: Higgins JPT, Altman DG, Sterne JAC (editors). Chapter 8: Assessing risk of bias in included studies. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions Version 5.1.0 (updated March 2011). The Cochrane Collaboration, 2011. Available from

Contributing authors: Doug Altman, Gerd Antes, Peter Gøtzsche, Julian Higgins, Peter Jüni, Steff Lewis, David Moher, Andy Oxman, Ken Schulz, Jonathan Sterne and Simon Thompson.

Acknowledgements: The material in this chapter was originally developed by a working group consisting of Doug Altman (co-lead), Gerd Antes, Chris Cates, Mike Clarke, Jon Deeks, Peter Gøtzsche, Julian Higgins (co-lead), Sally Hopewell, Peter Jüni (core group), Steff Lewis, Philippa Middleton, David Moher (core group), Andy Oxman, Ken Schulz (core group), Nandi Siegfried, Jonathan Sterne and Simon Thompson. The 2010 revision of the tool arose from an evaluation project involving Doug Altman (core group), Elaine Beller, Sally Bell-Syer, Isabelle Boutron, Chris Cates, Rachel Churchill, June Cody, Jonathan Cook, Christian Gluud, Julian Higgins (core group), Sally Hopewell, Hayley Jones, Peter Jűni, Monica Kjeldstrøm, Toby Lasserson, Allyson Lipp, Lara Maxwell, Joanne McKenzie, David Moher (core group), Craig Ramsey, Barney Reeves, Jelena Savović (co-lead), Jonathan Sterne (co-lead), David Tovey, Lucy Turner and Laura Weeks (core group). We thank Hilda Bastian, Rachelle Buchbinder, Iain Chalmers, Miranda Cumpston, Sally Green, Peter Herbison, Victor Montori, Hannah Rothstein, Georgia Salanti, Guido Schwarzer, Ian Shrier, Jayne Tierney, Ian White and Paula Williamson for helpful comments. For details of the Cochrane Statistical Methods Group, see Chapter 9 (Box 9.8.a) and for the Cochrane Bias Methods Group, see Chapter 10 (Box 10.5.a).