NHLBI Workshop

Data Needs for Cardiovascular Events, Management, and Outcomes

National Ambulatory Medical Care Survey (NAMCS) - Dr. Jane Sisk


National Ambulatory Medical Care (NAMCS) Scope

  • Non-federal, office-based physicians in direct patient care
  • Physicians excluded: Anesthesiology, radiology, and pathology
  • Out-of-scope settings
    • Hospital outpatient clinics, emergency depts.
    • Ambulatory surgicenter
    • Institutional settings (schools, prisons)
    • Federally operated clinic

Multistage National Probability Sample

  • 3-stage sampling
    • 112 geographic areas
    • 15 strata of physician specialties
    • About 30 visits sampled during 1 week
  • 1,500 physicians participate (about 70%)

Physician Characteristics, 2002

  • 55% under age 50
  • 21% female
  • 20% general/family practice; 13% internal medicine; 4% cardiovascular diseases
  • 86% metropolitan statistical area
  • 36% south, 18% northeast, 23% Midwest, 22% west

Practice Characteristics, 2002

  • 34% solo
  • 41% single-specialty group
  • 73% physician owned
  • 17% use electronic medical records
  • 84% have managed care contracts
  • Average percentage revenue
    • 48% private insurance
    • 30% Medicare
    • 12% Medicaid

Patient Characteristics

  • Age; Gender; Ethnicity/race; Vital signs; Tobacco use; Reason for visit; ZIP
  • Expected payment; Continuity; Disease management; Diagnoses.

Medical Care

  • Diagnostic testing/screening: Physical examination; Blood; Imaging; EKG
  • Counseling
  • Procedures
  • Treatment ordered
  • Medications/immunizations
  • Providers
  • Disposition
  • Time with physician

How Are the Data Used?

  • Management of specific medical conditions
  • Quality assessment and monitoring
  • Access to care
  • Disparities among subgroups
  • Diffusion of health-care technologies
  • Effects of policy changes
  • Benchmarks for states
  • Capacity and responsiveness of system

Number (in millions) and rate (per 100 persons) of physician office visits for diabetes [Grant et al. Arch Intern Med 2004;164(10):1134-1139]:

Year 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002
Number 14.3 17.1 17.3 15.1 16.8 18.9 20.8 25.5 23.8 26.1 27 24.9
Rate 5.7 6.8 6.8 5.8 6.4 7.1 7.8 9.5 8.8 9.4 9.6 8.8


Visits by Hypertensive Patients in Past 12 Months, 2001 NAMCS and NHAMCS

Number of visits during past 12 months
Percent
1 visit or new patient
8.7
2-3 visits
21.6
4-6 visits
32.6
7+ visits
30.3
Unknown
6.9

Percent of Patients with Hypertension and Diabetes Prescribed an Antihypertensive, by Therapeutic Class, 2001

Antihypertensives
ACE Inhibitor
Calcium Channel Blocker
Beta Blocker
Diuretic
Other Antihypertensive Drug
% of Patients
58.9
38.4
26.3
31.2
29.9

Continuing Challenges

  • Cover changes in technology and delivery
  • Obtain richer clinical data
  • Track medical management and health outcomes over time
  • Cover range of specialties and organizations
  • Anticipate and respond to clinical and public policy concerns

Back to Workshop Agenda

Skip footer links and go to content
Twitter iconTwitterExternal link Disclaimer         Facebook iconFacebookimage of external link icon         YouTube iconYouTubeimage of external link icon         Google+ iconGoogle+image of external link icon