The systematic review process was developed by the CCO-PEBC. The PEBC is supported by the Ontario Ministry of Health and Long-term Care. All work produced by the PEBC is editorially independent from the Ministry. This evidentiary base is composed of three parts: the evidentiary base of Version 2, the results of the updated search executed in March 2012 and the content of a further update executed in October 2013. Each of the searches was developed using a planned two-stage method and this document reports the methods used for the most recent update; methods for previous versions are very similar and are available upon request. The working group of the Hematology DSG comprising physicians with content expertise, epidemiologists and consumers developed this evidentiary base upon which these guideline recommendations are based.