Conflicts of interest

This volume has been critically appraised by two doctors (JML & JABC) who have no contact with commercial interests such as pharmaceutical companies. In order to reassure readers, and in the light of recent studies which have shown that writers of guidelines often have overt and covert connections with drug companies,Janice Tanne (2005) "Doctors who write guidelines often have ties to the drug iundustry"  BMJ  331, p.982. we wish to place on record that there has been no covert pressure to exclude or include certain drugs in this text, they have adhered to a policy of not seeing representatives from any such commercial company, and neither are they in receipt of any gifts, grants, or hospitality from such companies.