Ambulatory medical care utilization estimates for 2006.

OBJECTIVES: This report presents statistics on ambulatory care visits to physician offices, hospital outpatient departments (OPDs), and hospital emergency departments (EDs) in the United States in 2006. Ambulatory medical care utilization is described in terms of patient, practice, facility, and visit characteristics.

METHODS: Data from the 2006 National Ambulatory Medical Care Survey (NAMCS) and National Hospital Ambulatory Medical Care Survey (NHAMCS) were combined to produce annual estimates of ambulatory medical care utilization.

RESULTS: Patients in the United States made an estimated 1.1 billion visits to physician offices and hospital OPDs and EDs, a rate of 381.9 visits per 100 persons annually. The overall visit rate was not significantly different for white and black persons. However, black persons had higher visit rates than white persons to hospital OPDs and EDs and lower visit rates to office-based surgical and medical specialists. Visit distribution by ambulatory care setting differed by poverty level in the patient's ZIP Code of residence, with higher proportions of visits to hospital OPDs and EDs as poverty levels increased. Between 1996 and 2006, visit rates to medical specialty offices climbed overall by 29 percent, with a significant increase noted for white patients but not black patients. The rate of OPD visits jumped from 25.4 visits per 100 persons in 1996 to 34.7 in 2006, whereas ED visits during the same period increased from 34.1 to 40.5 per 100 persons. About 18.3 percent of all ambulatory care visits in 2006 were for nonillness or noninjury conditions, such as routine checkups and pregnancy exams. Seven in ten ambulatory care visits had at least one medication provided, prescribed, or continued in 2006, for a total of 2.6 billion drugs overall. Analgesics were the most common therapeutic category, accounting for 13.6 drugs per 100 drugs prescribed, and they were most often utilized at primary care and ED visits. The percentage of visits at which medication was prescribed increased significantly in most settings between 1996 and 2006.