This bibliography is compiled by clinicians from the journals listed at the end of this publication. It is based on literature entered into our database between 1 December 2007 and 30 November 2008 (articles are generally added to the database about two and a half months after publication). In addition, the bibliography contains every paper annotated by reviewers; these references were obtained from a variety of bibliographic databases and published between the beginning of the review period and the time of going to press. The bibliography has been grouped into topics that relate to the reviews in this issue.
• Papers considered by the reviewers to be of special interest
•• Papers considered by the reviewers to be of outstanding interest
The number in square brackets following a selected paper, e.g. , refers to its number in the annotated references of the corresponding review.