Introduction
The guideline group was selected to be representative of UK-based medical experts, experienced district general hospital haematologists and a patient representative. MEDLINE and EMBASE were searched systematically for publications in English from 2004 to 2008 using key word aplastic anaemia. The writing group produced the draft guideline which was subsequently revised by consensus by members of the General Haematology Task Force of the British Committee for Standards in Haematology. The guideline was then reviewed by 59 practising UK haematologists, the BCSH (British Committee for Standards in Haematology) and the British Society for Haematology Committee and comments incorporated where appropriate. Criteria used to quote levels and grades of evidence are as outlined in appendix 3 of the Procedure for Guidelines Commissioned by the BCSH (http://www.bcshguidelines.com/process1.asp#App3) and given at the end of this Guideline as Appendix I. The objective of this guideline is to provide healthcare professionals with clear guidance on the diagnosis and management of patients with acquired aplastic anaemia. The guidance may not be appropriate to patients with inherited aplastic anaemia and in all cases individual patient circumstances may dictate an alternative approach. Because aplastic anaemia is a rare disease, many of the statements and comments are based on review of the literature and expert or consensus opinion rather than on clinical studies or trials.