The National Hospital Ambulatory Medical Care Survey (NHAMCS), conducted by the National Center for Health Statistics (NCHS), collects annual data on visits to emergency departments to describe patterns of utilization and provision of ambulatory care delivery in the United States. Data are collected from nonfederal, general, and short-stay hospitals from all 50 U.S. states and the District of Columbia, and are used to develop nationally representative estimates.

The data include counts and rates of emergency department visits from 2016-2022 for the 10 leading primary diagnoses and reasons for visit, stratified by selected patient and hospital characteristics. Rankings for the 10 leading categories were identified using weighted data from 2022 and were then assessed in prior years.

These data include counts and rates of emergency department visits from 2016-2022 for selected primary diagnoses and reasons for visit, stratified by selected patient and hospital characteristics.
Search, visualize, and download these and other estimates from over 120 health topics with the NCHS Data Query System (DQS), available from: https://www.cdc.gov/nchs/dataquery/index.htm.

The National Hospital Ambulatory Medical Care Survey (NHAMCS) has been fielded annually since 1992 to collect data on the utilization and provision of ambulatory care services in hospital emergency and outpatient departments. Data collection from hospital-based ambulatory surgery centers began in 2009. And between 2010 and 2012 NHAMCS gathered data on visits to freestanding ambulatory surgery centers. In 2018, the survey began focusing on just the ambulatory visits made to emergency departments.
Each emergency department is randomly assigned to a 4-week reporting period. During this period, data for a systematic random sample of visits are recorded by Census interviewers using a computerized Patient Record Form. Data are obtained on patient characteristics such as age, sex, race, and ethnicity, and visit characteristics such as patient’s reason for visit, provider’s diagnosis, services ordered or provided, and treatments, including medication therapy. In addition, data about the facility are collected as part of a survey induction interview.

List of footnotes, notes, and source information for The National Hospital Ambulatory Medical Care Survey (NHAMCS). Each row of this dataset contains the accompanying text for a footnote found in NHAMCS dataset. The footnote lookup can be merged onto any NHAMCS dataset using, DATASET_SHORT_NAME, FN_ID, FN_TYPE, and FN_TEXT.

SOURCE: National Center for Health Statistics CDC, The National Hospital Ambulatory Medical Care Survey (NHAMCS)

The National Hospital Ambulatory Medical Care Survey (NHAMCS) has been fielded annually since 1992 to collect data on the utilization and provision of ambulatory care services in hospital emergency and outpatient departments. Data collection from hospital-based ambulatory surgery centers began in 2009. And between 2010 and 2012 NHAMCS gathered data on visits to freestanding ambulatory surgery centers. In 2018, the survey began focusing on just the ambulatory visits made to emergency departments.
Each emergency department is randomly assigned to a 4-week reporting period. During this period, data for a systematic random sample of visits are recorded by Census interviewers using a computerized Patient Record Form. Data are obtained on patient characteristics such as age, sex, race, and ethnicity, and visit characteristics such as patient’s reason for visit, provider’s diagnosis, services ordered or provided, and treatments, including medication therapy. In addition, data about the facility are collected as part of a survey induction interview.