VERDICT Health Services Research Center of Excellence, South Texas Veterans Health Care System, San Antonio, TX 78229-5700, USA
Accepted for publication 25 July 2002
Correspondence to: P Hitchcock Noël [email protected]
This material is the result of work supported with the resources and facilities at the South Texas Veterans Health Care System, San Antonio, Texas. The views expressed in this article are those of the authors and they do not necessarily represent those of the US Department of Veterans Affairs.
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