|Dataset full name:
||National Ambulatory Medical Care Survey
||The National Center for Health Statistics conducts the National Ambulatory Medical Care Survey (NAMCS) to measure the health care utilization and delivery of ambulatory services across various providers in the US. NAMCS is based on a sample of patient visits to a representitive sample of non-federal employed office-based physicians primarily engaged in direct patient care. The physician/office survey collects a wide variety of information at the physician/office level while the patient level data includes detailed information regarding reason for visit, vital signs, diagnosis and treatments. The NAMCS uses a multistage probability sample design. First stage: geographic primary sampling units are selected. Second stage: physician practices within geographic primary sampling units are selected. Third stage: random sample of patient visits to selected physicians is selected. Weights are provided to develop nationally representitive estimates. NAMCS does not include visits to hospital emergency departments, outpatient departments, department of veterans affairs, occupational health clinics, and institutional clinics.
||Ambulatory, CDC, Physician visit, Statistics, Survey, Physician office
||Centers for Disease Control and Prevention (CDC): National Center for Health Statistics (NCHS)
||Health conditions/Disability measures
||All (ICD-9 diagnostic codes), Arthritis, Asthma, Cancer, Cerebrovascular disease, Congestive heart failure, Chronic renal failure, Chronic obstructive pulmonary disease, Depression, Diabetes, Hyperlipidemia, Hypertension, heart disease, Obesity, Osteoporosis
||Measures/outcomes of interest
||Physician practice characteristics and specialty, Patient characteristics, Reason for visit, Medical providers seen, Time provider spent with patient, Continuity of care, Primary diagnosis at visit, Comorbid conditions, Vital signs, Diagnostic/screening services, Immunizations, Medications, demographic & regional information, non-medication treatments and proceedures performed/provided, Stage of cancer, Laboratory test results, Health education ordered or provided at visit
||Non-federally employed office-based physicians practices and patient visits
||2008: Number of Physicians :1,334
28,741 Patient Record forms (PRFs)
|Unit of Observation
||Patient (Physician-patient interaction or visit)
|Data Collection Mode
||Survey - completed by physician or office staff
** Over half of the Patient Record forms submitted in 2008 were abstracted by Census Bureau staff from patient records (rather than by physician or medical office staff).
||Annually from 1973 to 1981, in 1985, and annually since 1989 - present.
|Data Collection Frequency
||Strengths and limitations
||The data includes weights designed to produce national estimates of ambulatory medical care services in the U.S. Contains very detailed information regarding patient reason for visit, diagnosis, vital signs, treatments and medications. Data can be used to measure health care utilization across various types of providers.
||Only includes office visits. Federally employed physicians as well as those practicing in the specialties of anesthesiology, pathology, and radiology are excluded from the sample.
Reporting biases due to non-response and incomplete response (physician response/participation rate in 2008 was 59.1% of those found eligible).
Approximately 33-35% of race & ethnicity data were missing in 2008
|Data Access Requirements
||Public Use Dataset
||NAMCS 2009 factsheets: http://www.cdc.gov/nchs/ahcd/factsheets.htm#2009
NAMCS web tables: http://www.cdc.gov/nchs/ahcd/web_tables.htm#2009
|Dataset components (where applicable)
||NAMCS restricted data : includes additional information and variables masked in the publically available NAMCS public use microdata files:
||2008 NAMCS Micro-data file documentation:
||NAMCS publication list: