Ambulatory medical care utilization estimates for 2005.

Objective: 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 2005. Ambulatory medical care utilization is described in terms of patient, practice, facility, and visit characteristics.

Methods: Data from the 2005 National Ambulatory Medical Care Survey (NAMCS) and the National Hospital Ambulatory Medical Care Survey (NHAMCS) were combined to produce averaged annual estimates of ambulatory medical care utilization.

Results: Patients in the United States made an estimated 1.2 billion visits to physician offices and hospital OPDs and EDs, a rate of 4.0 visits per person annually. Between 1995 and 2005, population visit rates increased by about 20% in primary care offices, surgical care offices, and OPDs; 37% in medical specialty offices; and 7% in EDs. The aging of the population has contributed to increased volume of visits because older patients have higher visit rates. Visits by patients 40-59 years of age represented about 28.5 percent in 2005, compared with 23.9 percent in 1995. Black persons had higher visit rates than white persons to hospital OPDs and EDs, but lower visit rates to office-based primary care and to surgical and medical specialists. In the ED, the visit rate for patients with no insurance was about twice that of those with private insurance; whereas for all types of office-based care, the visit rates were higher for privately insured persons than for uninsured persons. About 29.4 percent of all ambulatory care visits were for chronic diseases and 25.2 percent were for preventive care, including checkups, prenatal care, and postsurgical care. The leading treatment provided at ambulatory care visits was medicinal with 71.3 percent of all visits having one or more medications prescribed, up by 10% since 1995 when encounters with drug therapy represented 64.9 percent of all visits. In 2005, 2.4 billion medications were prescribed or administered at these visits.