**APPENDIX C**

**\
**glossary of terms

This glossary defines terms used in data collection activities,
analyses, and publications associated with the emergency department (ED)
component of the Drug Abuse Warning Network (DAWN).

**Case description:** A description of how the drug(s) was related to
the patient's ED visit. The case description, in conjunction with the
chief complaint and diagnosis, is used to determine if the ED visit is
reportable to DAWN. It is copied verbatim from the patient's chart when
possible.

**Chief complaint:** The symptom(s) or condition(s) for which the
patient was seeking treatment in the ED. Includes the following
categories:

-   *Overdose* -- A condition associated with consumption of an
    excessive or toxic quantity of a drug or other substance.

-   *Intoxication* -- The condition produced by the toxic effect of a
    drug(s), often alcohol.

-   *Seizures* -- Neurologic events associated with abnormal electrical
    activity in the brain. Seizures manifest clinically as a change in
    consciousness, motor sensory, or behavioral symptoms.

-   *Altered mental status* -- Abnormal changes in basic mental
    functioning. Patient or those in attendance may state that the
    patient manifests symptoms of disorientation as to time and place,
    is delirious, is having hallucinations, is combative, or things of
    that nature.

-   *Psychiatric condition* -- In DAWN, a general term used to denote
    mental illness or psychological dysfunction, specifically those
    mental, emotional, or behavioral problems not caused by a physical
    disease. These include suicidal ideation, depression, schizophrenia,
    bipolar disorder, and so forth.

-   *Withdrawal* -- The physical state/symptoms produced by abstention
    from drugs to which the person is addicted.

-   *Seeking detox* -- Cases characterized by documentation in the chart
    that the patient is seeking "detox," "rehab," or medical clearance
    or help for a drug problem.

-   *Accident/injury/assault* -- Cases involving self-inflicted injuries
    or injuries resulting from fights, accidents, or assaults with
    documented use of substances.

-   *Abscess/cellulitis/skin/tissue* -- Cases involving cellulitis,
    abscess, infection, or skin problems such as rashes.

-   *Chest pain* -- A category of symptoms associated with pain or
    discomfort in the chest or upper thorax.

-   *Respiratory problems* -- A category of conditions associated with
    breathing. Examples include shortness of breath, coughing, and
    wheezing.

-   *Digestive problems* -- A category of conditions associated with the
    gastrointestinal system. Examples include indigestion, nausea,
    vomiting, diarrhea, and constipation.

-   *Other* -- Complaints that do not fit into the pre-recorded
    categories.

**Coterminous U.S.:** The contiguous 48 States and Washington, DC;
excludes Alaska and Hawaii.

**Diagnosis:** The condition(s) for which the patient was treated as
determined by the clinician after study.

**Disposition:** The location or facility to which an ED patient was
referred, transferred, or released.

*Treated and released* includes three categories:

-   *Discharged home* -- "Home" is used as a broad category to mean
    discharged to the patient's residence. Home is generally used for
    people who live locally; however, for students at nearby
    universities, home means their university; for travelers who get
    sick on the road, it may mean their hotel or wherever they are
    staying, and so forth.

-   *Released to police/jail*

-   *Referred to detox/treatment* -- The chart indicates that the
    patient was referred to a substance abuse treatment or detox
    facility or provider.

    *Admitted to this hospital* includes five categories:

-   *ICU/Critical care*

-   *Surgery*

-   *Chemical dependency/detox*

-   *Psychiatric unit*

-   *Other inpatient unit* -- The inpatient unit was not specified or
    does not match one of the preceding units.

    *Other disposition* includes five categories:

-   *Transferred --* The patient was transferred to another health care
    facility.

-   *Left against medical advice* -- The patient left the treatment
    setting without a physician's approval.

-   *Died* -- The patient died after arriving in the ED but before being
    discharged, admitted, or transferred.

-   *Other* -- The discharge status is documented in the chart but does
    not fit into any of the preceding categories.

-   *Not documented*

**Drug**: This refers to a substance that was recorded in a DAWN case
report. In addition to alcohol, up to 6 substances ("drugs") can be
reported for each ED visit. Therefore, the total number of drugs exceeds
the total number of ED visits. Even when only one drug is reported, it
should not be assumed that the substance was the sole and direct cause
of the visit; allowances should be made for reportable drugs not listed
or other contributory factors. (See also **Single-drug case**.)

**Drug category:** A generic grouping of pharmaceuticals and other
substances reported to DAWN, based on the classification of Multum
Information Services. Multum Information Services is a subsidiary of the
Cerner Corporation and a developer of clinical drug information systems
and a drug knowledge base. More information is available at
<http://www.multum.com/>. In general, the Multum categories follow the
therapeutic uses for prescription and over-the-counter pharmaceuticals.

Additional clarification is provided for the following drug categories:

-   *Alcohol alone* -- DAWN collects data on alcohol when used alone
    only if the patient is under age 21.

-   *Alcohol-in-combination* -- Alcohol-in-combination is the category
    for alcohol present in combination with another reportable
    substance. DAWN does not gather data on alcohol used alone, if the
    patient is over age 21. For patients 21 and older, alcohol must be
    used with another substance to be reported. Alcohol-in-combination
    is reportable for all ages.

-   *Amphetamines* -- This class of substances has been extracted from
    the category of central nervous system (CNS) stimulants because of
    its importance as a major substance of abuse. For purposes of
    classification, "amphetamines" (plural) includes a class of
    compounds derived from or related to the drug amphetamine. Although
    some "designer" drugs fall into the class of amphetamines, we choose
    to report some of them individually as major substances of abuse
    (e.g., methamphetamine). This category does not include other CNS
    stimulants, such as caffeine or methylphenidate.

-   *Combinations not tabulated above (NTA)* -- This category includes
    combinations composed of two or more major substances of abuse that
    are mixed and taken together. For example, "speedball," which
    usually refers to the combination of heroin and cocaine taken at
    once, would be classified as a combination NTA, whereas heroin and
    cocaine used separately would be classified separately in the
    categories heroin and cocaine. Combinations consisting of a major
    substance of abuse and another substance are classified in the
    category of the major substance (e.g., heroin with scopolamine is
    classified as heroin).

-   *Inhalants* -- This category includes anesthetic gases and
    psychoactive non-pharmaceutical substances for which the documented
    route of administration was inhaled, sniffed, or snorted.
    Psychoactive non-pharmaceuticals fall into one of the following 3
    categories: (1) **volatile solvents** -- adhesives (model airplane
    glue, rubber cement, household glue), aerosols (spray paint,
    hairspray, air freshener, deodorant, fabric protector), solvents and
    gases (nail polish remover, paint thinner, correction fluid and
    thinner, toxic markers, pure toluene, cigar lighter fluid, gasoline,
    carburetor cleaner, octane booster), cleaning agents (dry cleaning
    fluid, spot remover, degreaser), food products (vegetable cooking
    spray, dessert topping spray such as whipped cream, whippets), and
    gases (butane, propane, helium); (2) **nitrites** -- amyl nitrites
    ("poppers," "snappers") and butyl nitrites ("rush," "locker room,"
    "bolt," "climax," "video head cleaner"); or (3)
    **chlorofluorohydrocarbons** (freons). Anesthetic gases (e.g.,
    nitrous oxide, ether, chloroform) are presumed to have been inhaled.

**Drug-related ED visit:** Any ED visit related to recent drug use. To
be a DAWN case, a drug needs only to be implicated in the visit; the
drug does not have to have caused the visit. One patient may make
repeated visits to an ED or to several EDs, thus producing a number of
visits. It is impossible to determine the number of unique patients
involved in the reported drug-related ED visits because no patient
identifiers are collected.

**Estimate:** A statistical estimate is the value of a parameter (such
as the number of drug-related ED visits) for the universe that is
derived by applying sampling weights to data from a sample.

**Hospital emergency department (ED):** Only hospitals that meet
eligibility criteria for DAWN are recruited to participate. To be
eligible, hospitals must be non-Federal, short-stay, general medical and
surgical facilities with EDs that are open 24 hours a day, 7 days a
week, and located in the coterminous United States. Specialty hospitals;
hospital units of institutions; long-term care facilities; pediatric
hospitals; hospitals operating part-time EDs; hospitals in Alaska and
Hawaii; and hospitals operated by the Veterans Health Administration and
the Indian Health Service are excluded.

**Metropolitan area:** An area comprising a relatively large core city
or cities and the adjacent geographic areas. Conceptually, these areas
are integrated economic and social units with a large population
nucleus. The current DAWN ED sample, which was designed in the 1980s, is
based on the definitions of Metropolitan Statistical Areas (MSAs) and
Primary Metropolitan Statistical Area (PMSAs) issued by the Office of
Management and Budget (OMB) in 1983, with a few exceptions.

**Not otherwise specified (NOS):** Catch-all category for substances
that are not specifically named in the listing. Terms are classified
into an NOS category only when assignment to a more specific category is
not possible based on information in the source documentation (ED
patient charts).

**Not tabulated above (NTA):** Designation used when categories are not
presented in complete detail; smaller units are combined in the NTA
category.

***p*-value:** A measure of the probability (p) that the difference
between two estimates could have occurred by chance, if the estimates
being compared were really the same. The larger the *p*-value, the more
likely the difference could have occurred by chance. For example, if the
difference between two DAWN estimates has a *p*-value of 0.01, it means
that there is a 1% probability that the difference observed could be due
to chance alone.

**Population:** See **Universe**.

**Precision:** The extent to which an estimate agrees with its mean
value in repeated sampling. The precision of an estimate is measured
inversely by its standard error (SE) or relative standard error (RSE).
In DAWN publications, estimates with RSEs of 50% or higher are regarded
as too imprecise to be published. ED table cells where such estimates
would have appeared contain the symbol "..." (3 dots). (See also
**Relative standard error**.)

**Race/ethnicity:** Beginning in January 2000, the race and ethnicity
categories collected on DAWN cases changed to match a change in the
standard protocol issued by the OMB in 1997. The 1997 protocol permits
separate reporting of race and Hispanic ethnicity; the ability to
capture more than one race for an individual; modifications in
nomenclature (e.g., "Black" was changed to "Black or African American");
division of certain categories ("Asian or Pacific Islander" was split
into two categories, "Asian" and "Native Hawaiian or Other Pacific
Islander"); and elimination of the "Other" category.

The race/ethnicity categories on the DAWN data collection forms are as
follows:

-   *White* -- A person having origins in any of the original peoples of
    Europe, the Middle East, or North Africa.

-   *Black or African American* -- A person having origins in any of the
    black racial groups of Africa.

-   *Hispanic or Latino* -- A person of Cuban, Mexican, Puerto Rican,
    South or Central American, or other Spanish culture or origin,
    regardless of race.

-   *Asian* -- A person having origins in any of the original peoples of
    the Far East, Southeast Asia, or the Indian subcontinent including,
    for example, Cambodia, China, India, Japan, Korea, Malaysia,
    Pakistan, the Philippine Islands, Thailand, and Vietnam.

-   *American Indian or Alaska Native* -- A person having origins in any
    of the original peoples of North and South America (including
    Central America), and who maintains tribal affiliation or community
    attachment.

-   *Native Hawaiian or Other Pacific Islander* -- A person having
    origins in any of the original peoples of Hawaii, Guam, Samoa, or
    other Pacific Islands.

-   *Not documented* -- Used when documentation of race is not available
    from source records.

> Despite the increased detail allowed by these categories, the actual
> race/ethnicity data reported to DAWN changed very little because race
> and ethnicity are often not documented with this level of specificity
> in patient/decedent records. As a result, we have retained the
> classification used previously to tabulate DAWN data. The one
> exception is that we now collapse the less commonly used categories
> into a category termed "Not tabulated above (NTA)" instead of "Other."
> Categories used to tabulate race and ethnicity data in the ED
> publications are:

-   *White* -- Anyone meeting the definition of white (above). Those who
    are identified as white and Hispanic are classified as Hispanic.

-   *Black* -- Anyone meeting the definition of black or African
    American (above). Those who are identified as black or African
    American and Hispanic are classified as Hispanic.

-   *Hispanic* -- Anyone whose ethnicity is Hispanic or Latino (above)
    is placed in the category Hispanic, regardless of race.

-   *Race/ethnicity NTA* -- This includes those categories that are too
    small to report independently including: 2 or more races, American
    Indian or Alaska Native, Asian, Native Hawaiian or Other Pacific
    Islander.

-   *Unknown* -- Race and ethnicity are unknown. Those who are
    identified only as Hispanic are classified as Hispanic.

**Relative standard error (RSE):** A measure of an estimate's relative
precision. The RSE of an estimate is equal to the estimate's standard
error (SE) divided by the estimate itself. For example, an estimate of
2,000 cocaine visits with an SE of 200 visits has an RSE of 10%. The
larger the RSE, the less precise the estimate. Estimates with an RSE of
50% or more are not published by DAWN. (See also **Precision** and
**Standard error**.)

**Sampling:** Sampling is the process of selecting a proper subset of
elements from the full population so that the subset can be used to make
inference to the population as a whole. A probability sample is one in
which each element has a known and positive chance (probability) of
selection. A simple random sample is one in which each member has the
same chance of selection. In DAWN, a sample of hospitals is selected in
order to make inference to all hospitals; DAWN uses simple random
sampling within strata.

**Sampling frame:** A list of units from which the ED sample is drawn.
All members of the sampling frame have a probability of being selected.
A sampling frame is constructed such that there is no duplication and
each unit is identifiable. Ideally, the sampling frame and the universe
are the same. The sampling frame for the DAWN hospital ED sample is
derived from the American Hospital Association (AHA) Annual Survey of
Hospitals.

**Sampling unit:** A member of a sample selected from a sampling frame.
For the DAWN sample, the units are hospitals, and data are collected for
all drug-related ED visits at the responding hospitals selected for the
sample.

**Sampling weights:** Numeric coefficients used to derive population
estimates from a sample.

**Standard error (SE):** A measure of the sampling variability or
precision of an estimate. The SE of an estimate is expressed in the same
units as the estimate itself. For example, an estimate of 10,000 visits
with an SE of 500 indicates that the SE is 500 visits.

**Strata** (plural), **stratum** (singular): Subgroups of a population
within which separate ED samples are drawn. Stratification is used to
increase the precision of estimates for a given sample size, or,
conversely, to reduce the sample size required to achieve the desired
level of precision. The DAWN ED sample is stratified into 21
metropolitan area cells plus an additional cell for the remainder of the
coterminous U.S. Then, within these cells strata are defined according
to the annual number of ED visits, whether the hospital is located
inside or outside the central city of the metropolitan area, and by the
presence or absence of an organized outpatient department,
alcohol/chemical dependence inpatient unit, or both. The strata are as
follows:

  -------------------------------------------------------------------------------
  **Stratum**    **Annual ED   **Location       **Outpatient department or
                 visits**      within           alcohol/chemical dependence
                               metropolitan     inpatient unit**
                               area**           
  -------------- ------------- ---------------- ---------------------------------
  **In the 21                                   
  DAWN                                          
  metropolitan                                  
  areas:**                                      

  0              \>80,000      Not applicable   Not applicable

  1              \<80,000      Central city     Both

  2              \<80,000      Central city     One only

  3              \<80,000      Central city     Neither

  4              \<80,000      Outside central  Both
                               city             

  5              \<80,000      Outside central  One only
                               city             

  6              \<80,000      Outside central  Neither
                               city             

  **In the                                      
  remainder of                                  
  the                                           
  coterminous                                   
  U.S.:**                                       

  0              \>80,000      Not applicable   Not applicable

  7              \<80,000      Not applicable   Both

  8              \<80,000      Not applicable   One only

  9              \<80,000      Not applicable   Neither

  Note: Stratum                                 
  "0" is defined                                
  for each of                                   
  the 21                                        
  metropolitan                                  
  areas and for                                 
  the remainder                                 
  of the                                        
  coterminous                                   
  U.S. See *Drug                                
  Abuse Warning                                 
  Network Sample                                
  Design and                                    
  Estimation                                    
  Procedures:                                   
  Technical                                     
  Report*,                                      
  November 1997.                                
  -------------------------------------------------------------------------------

**Statistically significant:** A difference between two estimates is
said to be statistically significant if the value of the statistic used
to test the difference is larger or smaller than would be expected by
chance alone. For DAWN ED estimates, a difference is considered
statistically significant if the *p*-value is less than 0.05. (See also
***p*-value**.)

**Single-drug visit:** A single-drug visit is one in which only one drug
was involved. Because multiple substances may be recorded for each DAWN
case (see **Drug**), readers should exercise caution in interpreting the
relationship between a given drug and the number of associated ED
visits. For example, if records for a given patient documented marijuana
use, this does not mean that marijuana was the only drug involved in the
ED visit or that the marijuana caused the ED visit. One should always
consider whether and how many other drugs were used in combination, but
even then attributing a causal relationship between the visit and a
particular drug may not be possible. Additionally, DAWN can only provide
single-drug visit totals for alcohol if the patient was younger than age
21.

**Type of case:** A classification used to group similar DAWN cases.
Each case is coded into one and only one category, the first that
applies from the following hierarchy: Suicide attempt, seeking detox,
alcohol only (age \< 21), adverse reaction, overmedication, malicious
poisoning, accidental ingestion, and *other*.

**Universe:** The entire set of units for which generalizations are
drawn. The universe for the DAWN ED sample is all non-Federal,
short-stay, general medical and surgical hospitals in the coterminous
United States with EDs operating 24 hours a day, 7 days a week. (See
also **Coterminous U.S.**).