1. Houston Center for Quality of Care and Uti-lization Studies, a Health Services Research and Development Center of Excellence, Michael E. Debakey VA Medical Center, and Section for Health Services Research and with Section on Hypertension-Clinical Pharmacology, Department of Medicine, Baylor College of Medicine, Houston, Tex
2. Houston Center for Quality of Care and Utilization Studies, a Health Services Research and Development Center of Excellence, Michael E. DeBakey VA Medical Center, and Section for Health Services Research, Department of Medicine, Baylor College of Medicine, Houston, Tex
3. Department of Veterans Af-fairs, Center for Health Quality, Outcomes and Economic Research, a Health Services Research and Development Center of Excellence, Bedford VA Medical Center, Bedford, Mass, and the Health Services Department, Boston University School of Public Health, Bedford, Mass
4. Houston Center for Quality of Care and Utilization Studies, a Health Services Research and Development Center of Excellence, Michael E. DeBakey VA Medical Center, and Section for Health Services Research, Department of Medicine, Baylor College of Medicine, Houston, Tex,