DISCLOSURES: Each author must disclose all fi nancial relationships for the previous 12 months, whether or not they are related to the subject of the paper. This should include equity ownership, profi t-sharing agreements, royalties, patents, and grants. Income from pharmaceutical companies should be specifi ed by type, e.g. speaker's honoraria, expenses, grants, etc. Authors do not need to report the sums concerned. If none, state "none".