# Presentation: 587639

## Mental Health Data from the NAMCS and NHAMCSSusan M. Schappert, M.A.Ambulatory and Hospital Care Statistics BranchDivision of Health Care Statistics

## Topics To Be Covered

- Survey Overview
- Data Collected
- Published Mental Health Research Using Data from NAMCS and NHAMCS
- User Considerations
- How to Get the Data

## An Overview of NAMCS and NHAMCS

##          NAMCS and NHAMCS

- National Ambulatory Medical Care Survey (NAMCS)
- Visits to office-based physicians
- National Hospital Ambulatory Medical Care Survey (NHAMCS)
- Visits to hospital emergency and outpatient departments (EDs and OPDs)

## History of NAMCS

- Planning began in 1967
- Inaugurated in 1973
- Fielded 1973-1981, 1985, 1989-present
- Database covering more than 30 years

## History of NHAMCS

- Planning began in 1976
- Inaugurated December 1991
- Fielded annually
- 17th year of operation

## NAMCS Sample Design

- Three stage design
- 112 primary sampling units (counties/groups of counties)
- Physician practices within PSUs
- Patient visits within practices
- About 3,000 physicians are selected
- Each physician is randomly assigned to a     1-week reporting period
- Data obtained for 25,000-30,000 patient visits
- Sample data must be weighted to produce national estimates

## Scope of the NAMCS

- Basic unit of sampling is the physician-patient visit
- In scope visits:
- Must occur in physician’s office
- Must be for medical purposes
- Administrative visits not sampled
- House calls, emails, phone calls not sampled

## Scope of the NAMCS

- Physicians must be:
- Classified by AMA or AOA as primarily engaged in office-based patient care
- nonfederally employed;
- not in anesthesiology, radiology, or pathology
- 59 percent response rate in 2006

## Physicians Sampled in the NAMCS

- Physicians are typically stratified into 15 specialty groups
- general and family practice, internal medicine, pediatrics, ob-gyn, general surgery, orthopedic surgery, cardiovascular diseases, dermatology, urology, psychiatry, neurology, ophthalmology, otolaryngology, and an “other” category
- 2006 included an additional sample of oncologists, and a sample of community health centers
- 29,392 Patient Record Forms completed by about 1,400 physicians in 2006
- 570+ primary care physicians (general and family practice, internal medicine, pediatrics, and ob-gyn) responded in 2006 with data on about 14,400 visits (nearly half of total visit records)
- 80+ psychiatrists reported on nearly 1,400 visits (4.7% of total)

## In-Scope NAMCS Locations 

- Freestanding clinic/urgicenter
- Federally qualified health center
- Neighborhood and mental health centers
- Non-federal government clinic
- Family planning clinic
- Health maintenance organization
- Faculty practice plan
- Private solo or group practice

## Out-of-Scope NAMCS Locations

- Hospital ED’s and OPD’s
- Ambulatory surgicenter
- Institutional setting (schools, prisons)
- Industrial outpatient facility
- Federal Government operated clinic
- Laser vision surgery

## NHAMCS Sample Design

- Multistage probability design
- First stage sample of 112 PSUs
- Hospitals within PSUs
- Clinics within OPDs, ESA (emergency service area) within EDs
- Patient visits within clinics, ESAs
- 4-week reporting period
- 486 hospitals sampled in 2006; 35,849  ED visits and 35,105 OPD visits

## Scope of the NHAMCS

- Basic unit of sampling is patient visit
- Emergency and outpatient departments of noninstitutional general and short-stay hospitals
- Not Federal, military, or Veterans Administration facilities
- Located in 50 states and D.C.

## Sampled OPD Clinics

- 6 clinic types are defined and used for sampling: general medicine, surgery, pediatrics, ob-gyn, substance abuse, and “other”
- “Other” includes anxiety, behavioral medicine, eating disorders, psychiatry (adult, child, pediatric, geriatric), mental health, mental hygiene, psychopharmacology, and sleep disorders
- Not included: partial hospitalization programs, day hospital programs, psychology, methadone maintenance

## Data Collected in the NAMCS and NHAMCS

## Data Collection

- U.S. Census Bureau is our field agent
- Induction interview to train medical office or hospital staff on data collection procedures and to obtain data on practice or facility characteristics
- Physician’s office/hospital staff is responsible for completion of Patient Record forms; Census abstracts as a last resort.  In 2006, more than one-third of NHAMCS forms and about one-half of NAMCS forms were completed by Census  abstraction.

## Data Collection

- Patient Record Forms (PRFs)
- Nearly identical for NAMCS and OPD
- Some differences for ED
- Redesigned once every 2 years
- Copies at our website: www.cdc.gov/nhcs/namcs.htm

## Data Items

- Patient characteristics
- Age, sex, race, ethnicity
- Visit characteristics
- Source of payment, continuity of care, reason for visit, diagnosis, treatment
-  Provider characteristics
- Physician specialty, hospital ownership, region and urban-rural status, use of electronic medical records, and much more
- Drug characteristics added in 1980

## Mental Health Items Collected inNAMCS and NHAMCS-OPD

- Patient’s reason for visit (all survey years)
- Physician’s diagnosis (all survey years)
- Does patient now have depression? (1991-92, 1995-96, 2005-06)
- Cause of injury (1995-2004), verbatim text added (1997-2004)
- Diagnostic/screening services ordered or provided
- Mental status exam (1979-81, 1991-92, 1995-96)
- Depression screening (2005-06)
- Medication therapy (1980-2006)
- Non-medication therapy ordered or provided
- Psychotherapy/therapeutic listening (1973-1981)
- Psychotherapy (1985-92, 1995-2006)
- Psycho-pharmacotherapy (1997-2000)
- Alcohol abuse counseling (1991-92)
- Drug abuse counseling (1991-92)
- Stress management counseling (1991-92, 1997-2000, 2005-06)
- Mental health counseling (1995-2000)
- Mental health/stress management counseling (2001-04)
- Other mental health counseling (2005-06)

## Mental Health Items Collected inNHAMCS-ED

- Patient’s reason for visit (all survey years), verbatim text added 2005-06
- Physician’s diagnosis (all survey years)
- Does patient now have depression? (1995-96)
- Cause of injury (1995-2006),  verbatim text added (1997-2006)
- Intentional injury? (1997-2006)
- Violence-related injury? (1995-96)
- Alcohol- or drug-related visit? (1992-96)
- Alcohol-related visit? (2001-04)
- Adverse drug event (2001-02)
- Patient oriented x 3 (2003-06)
- Medication therapy (all survey years)

## Multiple Response Fields

- Up to 3 reasons for visit, causes of injury, physician diagnoses can be reported for each visit (no cause of injury on NAMCS and OPD starting in 2005)
- Up to 8 medications and each medication can have up to 3 therapeutic classes and up to 5 ingredients
- Multiple procedure codes for NAMCS and OPD

## Coding Systems Used

- Reason for Visit Classification (NCHS)
- ICD-9-CM for diagnoses, causes of injury, and procedures
- Drug Classification System (NCHS)
- Multum Lexicon starting with 2006 data (previously used National Drug Code Directory)

## Drug Data in NAMCS/ NHAMCS

**	**
**    **Respondents may list up to 8 medications (including Rx, or prescription, and OTC, or over-the-counter, medications, immunizations, allergy shots, anesthetics, and dietary supplements) that were ordered, supplied, administered, or continued during the visit.
- 	Each entry is called a drug mention.  Visits with one or more drug mentions are called drug visits.
- 	Respondents are asked to report trade names or generic names only (not dosage, administration, or regimen).  Cannot link drugs with diagnosis.
**	**
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**Notes:**
Several difficulties of collecting drug data on surveys that should be understood.
First, there are multiple names for any given product. There are at least the following 3 
The chemical name
the trade or brand name
chosen by the manufacturers
& then the generic name
which is assigned by the 
and it is really the official name of the drug & is more commonly used by the gov’t & researchers because it is not associated with a particular company. 
As a consequence of the multiple names, survey drug data collection is complicated by the fact that participants may report the generic or trade names

## NAMCS or NHAMCS drug data can be analyzed 
at the visit level (for example, the number of visits at which a particular drug was prescribed)
or at the medication level (for example, the number of “mentions” of a particular drug at ambulatory care visits

- at the visit level (for example, the number of visits at which a particular drug was prescribed)
- or at the medication level (for example, the number of “mentions” of a particular drug at ambulatory care visits

## Published Mental Health Research Using Data from NAMCS and NHAMCS

## Hot Topics

- See the NAMCS/NHAMCS website for a complete list of publications (including journal articles) by NCHS and others that use our data (about 100 focus on mental health) – updated monthly
- Mental health research using NAMCS/NHAMCS data includes:
- visits for specific diagnoses (depression, ADHD [attention deficit/hyperactivity disorder], and sleep disorders have been most commonly published, but there are also studies on visits for anxiety disorders, bipolar disorder, autism, schizophrenia)
- pharmacotherapy (antidepressants, antipsychotics, hypnotics, stimulants, psychotropics in general)
- mental health care by physicians other than psychiatrists
- racial/ethnic/gender disparities in mental health care
- other topics such as self-harm (ED visits), insurance issues, substance abuse

## Additional Mental Health Data from NAMCS and NHAMCS

- Many annual NCHS summary reports (for example, Health US) include mental health related data, such as trends in prescribing antidepressants
- Annual NAMCS and NHAMCS summary reports can include various mental health-related statistics (for example, statistics on visits to psychiatrists within tables by physician specialty)
- Some NCHS reports have focused specifically on visits to psychiatrists, alcohol/drug related visits, etc.

## User Considerations

## A few things to keep in mind...

- NAMCS/NHAMCS sample visits, not patients
- No estimates of incidence or prevalence
- No state-level estimates
- We do not sample by setting or by non-physician providers with one exception:
- Note that, from 2006, NAMCS includes a stratum of CHCs (community health centers), and non-physician providers are sampled within CHCs
- May capture different types of care for solo vs. group practice physicians
- May not have much data in a single year for less common conditions or events

## NAMCS vs. NHAMCS

- Consider what types of settings are best for a particular analysis
- Persons of color are more likely to visit OPDs and EDs than physician offices
- Persons in some age groups make disproportionately larger shares of visits to EDs than offices and OPDs

## Ways to Improve Reliability of Estimates

- Combine NAMCS, ED, and OPD data to produce ambulatory care visit estimates
- Combine multiple years of data
- Aggregate categories of interest into broader groups.

## Caveat on Counseling Services

- Diagnostic services are reflected accurately on medical records, but counseling services may not be
- NAMCS (and OPD) data may underestimate the amount of health habit counseling that occurs if it is not documented in the medical record
- These findings were published by in the following article: Gilchrist VJ, Stange KC, Flocke SA, McCord G, Bourguet CC. A Comparison of the National Ambulatory Medical Care Survey (NAMCS) Measurement Approach With Direct Observation of Outpatient Visits. Medical Care 42(3), March 2004, 276-280.

## How To Get the Data

## http://www.cdc.gov/nchs/namcs.htm

## Public Use Micro-data Files

- Downloadable files
- NAMCS, 1973-2006
- NHAMCS, 1992-2006
- CD-ROMs
- NAMCS, 1990-2005
- NHAMCS, 1992-2005

## Enhanced Public Use Files

- SAS input statements, label statements, and format statements (1993-2006)
- SPSS and Stata code for 2002-2006
- Masked sample design variables
- Allow use of SUDAAN, Stata, etc.
- Available for 1993-2006

## NCHS Research Data Center

## Advantages of the NCHSResearch Data Center

- Users gain access to information not available on public use files
- Patient: ZIP code-linked income, education, poverty status, percent foreign born, percent not speaking English well, urban-rural classification
- Provider: physician sex, age, and board certification, teaching hospital
- Geographic: FIPS (Federal Information Processing Standard) state and county codes
- Special files and data supplements
- For a complete list of variables, contact the Ambulatory and Hospital Care Statistics Branch

## Research Data Center – cont.

- Can merge with contextual variables (e.g., Area Resource File, National Health Interview Survey, National Hospital Discharge Survey Census)
- Health status level
- Health Maintenance Organization (HMO) penetration
- Physician and specialist supply
- Medicaid reimbursement
- Air quality
- Percent in poverty

## Research Data Center Procedures

- Submit a proposal
- May not use data to identify patients or providers or geographic location of providers
- May not remove data files
- Fees vary based on whether use is onsite or remote and whether project requires file construction by NCHS staff

## Research Data Center

- E-mail:  rdca@cdc.gov
- Website:   www.cdc.gov/nchs/r&d/rdc.htm
- Call (301) 458-4277

## Additional Information

- Call the Ambulatory and Hospital Care Statistics Branch at (301) 458-4600
- Visit our website at www.cdc.gov/nhcs/namcs.htm
- Join the ACLIST. It’s a moderated newsgroup for persons interested in NAMCS/NHAMCS.  It currently consists of about 2,600 subscribers.
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