1. A reason for visit classification for ambulatory care;Schneider;Vital Health Stat 2,1979
2. National Ambulatory Medical Care Survey: 1991 summary;Schappert;Vital Health Stat 203,1993
3. Sample design, sampling variance, and estimation procedures for the National Ambulatory Medical Care Survey;Bryant;Vital Health Stat 2,1988
4. The National Ambulatory Medical Care Survey;Hoermann;Med Care,1973
5. The emerging role of physician assistants in the delivery of dermatologic health care;Clark;Dermatol Clin,2000