Principal Investigator(s): United States Department of Health and Human Services. Centers for Disease Control and Prevention. National Center for Health Statistics
The National Hospital Ambulatory Medical Care Survey (NHAMCS) provides data from samples of patient records selected from emergency departments (EDs) and outpatient departments (OPDs) of a national sample of hospitals. The resulting national estimates describe the use of hospital ambulatory medical care services in the United States. For the 2003 survey, data were collected from 236 OPDs and 475 EDs. Among the variables included are age, race, and sex of the patient, reason for the visit, physician's diagnoses, cause of injury (EDs only), surgical procedures (OPDs only), medication therapy, and expected source of payment. For 2003, additional updates and revisions have been made to the drug characteristics data. The variables CSTRATM and CPSUM have been added to assist in the computation of variances.
These data are freely available.
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United States Department of Health and Human Services. Centers for Disease Control and Prevention. National Center for Health Statistics. National Hospital Ambulatory Medical Care Survey, 2003. ICPSR04406-v2. Ann Arbor, MI: Inter-university Consortium for Political and Social Research [distributor], 2011-10-12. http://doi.org/10.3886/ICPSR04406.v2
Persistent URL: http://doi.org/10.3886/ICPSR04406.v2
Scope of Study
Subject Terms: ambulatory care, emergency services, health care services, hospitalization, hospitals, injuries, medical care, medical evaluation, medical procedures, medical records, patient care, patients, payment methods, surgery, treatment
Geographic Coverage: United States
Date of Collection:
Universe: Visits to the emergency and outpatient departments of noninstitutional general and short-stay hospitals within the 50 states and the District of Columbia, which had an average length of stay of less than 30 days, or to hospitals whose specialty was general (medical or surgical) or children's general. Excluded were federal hospitals, hospital units within institutions, and hospitals with less than six beds staffed for patient use.
Data Types: administrative records data
Data Collection Notes:
Per agreement with NCHS, ICPSR distributes the data files and text of the technical documentation for this collection as prepared by NCHS.
Detailed information regarding the use of weight variables and variance estimation is located in the User Guide.
The Stata dataset (.dta file) made available by ICPSR does not contain all of the value labels found within the .do file supplied by ICPSR. Specifically, the value labels that are composed primarily of ICD-9 codes have been omitted from the .dta file. Those data users interested in applying the value labels to the dataset will be able to edit the Stata setup files, which include the aforementioned labels, provided by ICPSR.
Sample: The NHAMCS used a four-stage probability design with samples of primary sampling units (PSUs), hospitals within PSUs, clinics within hospitals, and patient visits within clinics.
Weight: Users should use the variable PATWT when performing analyses.
Patient visit records from hospital emergency departments and outpatient departments.
Original ICPSR Release: 2006-02-17
- 2011-10-12 Changes to the CSTRATM variable have been made within the Outpatient Department dataset.
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