Roles and responsibilities*
Task	Who carried out this task?
Drafting of protocol	Sophia Papadakis, George Wells, Andrew Pipe
Development of search strategy	Sophia Papadakis, Gillian Pritchard, Lindsay Stead (editorial)
Searched for trials	Sophia Papadakis, Gillian Pritchard
Obtained copies of trials	Gillian Pritchard
Eligibility assessment	Sophia Papadakis, Gillian Pritchard, Andrew Pipe, Bosun Hong, Nicola Lindson
Extracted data	Sophia Papadakis, Gillian Pritchard, Nicola Lindson, Bosun Hong
Entered data into Review Manager 5	Sophia Papadakis, Gillian Pritchard, Nicola Lindson, Bosun Hong
Carried out analysis	Sophia Papadakis, Nicola Lindson, Thomas Fanshawe
Interpreted analyses	Nicola Lindson
Drafting the final review	Sophia Papadakis, Nicola Lindson, Thomas Fanshawe; Bosun Hong
Review of draft	All authors