Health Care Statistics: Ambulatory Medical Care-Part II of a IV Part Series

(8/21/07)- Statistics are now available from the 2005 National Hospital Ambulatory Medical Care Survey (NHAMCS), a national probability survey of visits to emergency and OPDs, of nonfederal, short-stay, and general hospitals in the United States. According to the survey definition, an OPD "is a hospital facility where nonurgent ambulatory medical care is provided under the supervision of a physician…[T]he nature of care provided in OPDs is also different from that provided in physician offices. For example, OPD visits have greater mentions of diagnostic and screening services being ordered or provided and higher frequency of care provided by mid-level providers".

Hospital OPDs had an estimated 90.4 million visits in 2005. Using census estimates of population, this comes to 31 visits per 100 persons, with females having 37.2 per 100, while males had 24.7 visits per 100 persons. Outpatient department visits account for only about 8% of ambulatory medical care. The largest proportion of ambulatory care visits occurs in physicians offices (about 49% of the total visits). The most frequent chronic condition listed as reason for visit was hypertension, accounting for 19.7% of the visits. In 42.4% of the visits, private insurance was listed as the most frequent source of payment. Medicare accounted for 16.8% of the source of payment. The emergency department visit rate of the uninsured is 45.9 visits per 100 persons, while in office based settings the rate is 23.8 visits per 100 persons.

Table 14 of the survey report suggests that 793000 visits to OPDs were the result of "adverse effect of medical or surgical care or adverse effect of medicinal drug". This accounted for 8.1% of the injury-related outpatient department visits. This dovetails with the article that appears in the August 19, 2007 issue of the NY Times-"Medicare Says It Won’t Cover ‘Preventable’ Hospital Errors". The article points out that "the Center for Disease Control and Prevention estimates that patients develop 1.7 million infections in hospitals each year and it says those infections cause or contribute to the death of 99000 people a year-about 270 per day." The Bush administration estimates this will save Medicare $20 million per year. The goal is to have hospitals follow well-established infection-control guidelines.

Hospitals are forbidden to charge patients fees for the error costs that Medicare will not cover. This means that hospital-acquired complications are not chargeable. The complications that Medicare will not pay include common strains of staphylococcus bacteria infections, bedsores, injuries caused by falls, and infections resulting from prolonged use of catheters in blood vessels or the bladder.

The NY Times ends the article with a quote from Dr. Kenneth W. Kizer, an expert on patient safety: "I applaud the intent of the new Medicare rules, but I worry that hospitals will figure out ways to get around them. The new policy should be part of a larger initiative to require the reporting of health care events that everyone agrees should never happen. Any such effect must include a mechanism to make sure hospitals comply."

Ref: 1. Middleton K., Hing E., Xu J. National Hospital Ambulatory Medical Care Survey: 2005 Outpatient Department Summary. CDC Advance Data 2007; 389:1-24

2. Pear, Robert. Medicare Says It Won’t Cover ‘Preventable’ Hospital Errors. NY Times August 19, 2007.

Please see: Health Care Statistics: Part I-National Hospital Discharges
Health Care Statistics: Part III- Assessing Health Care in the U.S.
Hospital Death Statistics: Part IV- Deaths


Harold Rubin, MS, ABD, CRC, Guest Lecturer
posted August 21, 2007

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