The National Ambulatory Medical Care Survey (NAMCS) is designed to meet the need for objective, reliable information about the provision and use of ambulatory medical care services in the United States. NAMCS began in 1973 as a national probability sample survey of visits to nonfederally employed office-based physicians. NCHS conducted the survey annually through 1981, again in 1985, and annually through 2021 (collection of visit data from physicians was stopped during 2020–2021 due to the burden placed on respondents by the COVID-19 pandemic). In 2006, a separate sample of Community Health Centers (CHCs) was added to the survey; the CHC component samples visits to both physicians and advanced practice providers (nurse practitioners, PAs [physician assistants and physician associates], and certified nurse midwives). Starting in 2012, in addition to the traditional NAMCS file, a separate data file for CHCs including physicians and advanced practice providers has been released.

In 2021, the former CHC sample of NAMCS was redesigned and launched as the NAMCS Health Center (HC) Component, collecting visit data from HCs using electronic health records, or EHR, systems of the participating health centers. The NAMCS Health Center Component contains critical data about health centers and the care they provide.

The National Hospital Care Survey (NHCS) collects data on patient care in hospital-based settings to describe patterns of health care delivery and utilization in the United States. Settings currently include inpatient and emergency departments (ED). From this collection, the NHCS contributes data that may inform emerging national health threats such as the current opioid public health emergency. The 2022 - 2024 NHCS are not yet fully operational so it is important to note that the data presented here are preliminary and not nationally representative.

The data are from 27 hospitals submitting inpatient and 20 hospitals submitting ED Uniform Bill (UB)-04 administrative claims from April 1, 2022–March 31, 2024. Even though the data are not nationally representative, they can provide insight into the use of opioids and other overdose drugs. The NHCS data is submitted from various types of hospitals (e.g., general/acute, children’s, etc.) and can show results from a variety of indicators related to drug use, such as overall drug use, comorbidities, and drug and polydrug overdose. NHCS data can also be used to report on patient conditions within the hospital over time.