The Drug Abuse Warning Network (DAWN) is a nationally representative public health surveillance system that has monitored drug related emergency department (ED) visits to hospitals since the early 1970s. First administered by the Drug Enforcement Administration (DEA) and the National Institute on Drug Abuse (NIDA), the responsibility for DAWN now rests with the Substance Abuse and Mental Health Services Administration's (SAMHSA) Center for Behavioral Health Statistics and Quality (CBHSQ). Over the years, the exact survey methodology has been adjusted to improve the quality, reliability, and generalizability of the information produced by DAWN. The current approach was first fully implemented in the 2004 data collection year.
DAWN relies on a longitudinal probability sample of hospitals located throughout the United States. To be eligible for selection into the DAWN sample, a hospital must be a non-Federal, short-stay, general surgical and medical hospital located in the United States, with at least one 24-hour ED. DAWN cases are identified by the systematic review of ED medical records in participating hospitals. The unit of analysis is any ED visit involving recent drug use. DAWN captures both ED visits that are directly caused by drugs and those in which drugs are a contributing factor but not the direct cause of the ED visit. The reason a patient used a drug is not part of the criteria for considering a visit to be drug related. Therefore, all types of drug-related events are included: drug misuse or abuse, accidental drug ingestion, drug-related suicide attempts, malicious drug poisonings, and adverse reactions. DAWN does not report medications that are unrelated to the visit.
The DAWN public-use dataset provides information for all types of drugs, including illegal drugs, prescription drugs, over-the-counter medications, dietary supplements, anesthetic gases, substances that have psychoactive effects when inhaled, alcohol when used in combination with other drugs (all ages), and alcohol alone (only for patients aged 20 or younger). Public-use dataset variables describe and categorize up to 16 drugs contributing to the ED visit, including toxicology confirmation and route of administration. Administrative variables specify the type of case, case disposition, categorized episode time of day, and quarter of year. Metropolitan area is included for represented metropolitan areas. Created variables include the number of unique drugs reported and case-level indicators for alcohol, non-alcohol illicit substances, any pharmaceutical, non-medical use of pharmaceuticals, and all misuse and abuse of drugs. Demographic items include age category, sex, and race/ethnicity. Complex sample design and weighting variables are included to calculate various estimates of drug-related ED visits for the Nation as a whole, as well as for specific metropolitan areas, from the ED visits classified as DAWN cases in the selected hospitals.
ICPSR data undergo a confidentiality review and are altered when necessary to limit the risk of disclosure. ICPSR also routinely creates ready-to-go data files along with setups in the major statistical software formats as well as standard codebooks to accompany the data. In addition to these procedures, ICPSR performed the following processing steps for this data collection:
Several limitations to the data exist and should be noted prior to using this DAWN file:
Information on drug-related ED visits is based on a sample and is, therefore, subject to sampling variability. Hospital participation rates in oversampled metropolitan areas typically have been 50 percent or higher. However, the participation rate in the remainder of the United States has been lower, in the range of 20 to 30 percent, since the DAWN redesign in 2003. In any sample survey, a low response rate is of concern because it creates the opportunity for bias. That is, nonparticipating hospitals may have different characteristics than participating hospitals, possibly including differences in the drugs reported, types of drug-related ED visits, patient disposition, or population demographics.
Although every effort is made during the data collection phase to collect data accurately and precisely, extant medical records vary in specificity and detail. Therefore, factors that may affect the reliability and accuracy of the findings include the following:
DAWN data collectors attempt to identify with a high degree of specificity the exact drugs involved in an ED visit. If extant medical records include only a general description of a drug (e.g., "benzodiazepines" or "opiates"), the drug is grouped in a general category (e.g., "benzodiazepines not otherwise specified"). Similarly, records often describe a drug as amphetamines without specifying if it is methamphetamine.
DAWN seeks to report only drugs that are related to the ED visit, not all the drugs or medications that the patient may be taking on a regular basis as prescribed by a doctor. If the ED record is not clear on this point, drugs may be included in the data that are not specifically related to the visit. For example, anecdotal evidence suggests that methadone may be over-reported when the medical records fail to mention that the patient is in a methadone treatment program. The opposite is also true; a current medication may be involved in the ED visit but not recognized as a contributing factor by the clinician.
Major changes to DAWN were instituted during 2003 as the result of a redesign intended to improve the quality and representativeness of DAWN estimates. Changes included the design of the hospital sample, a new case definition for drug-related ED visits eligible for DAWN, revised data items submitted on these cases, a new protocol for case finding, and improved quality assurance measures. These improvements created a permanent disruption in trends. As a result, comparisons cannot be made between the old DAWN (2002 and prior years) and the redesigned DAWN (2004 and forward). The year 2003 was a period of transition between the old DAWN and the redesigned DAWN. As a result, only interim, half-year estimates were produced for 2003.
Several measures have been taken to protect the confidentiality of DAWN data:
In the public use file, complex design variables have been adjusted to optimize disclosure protection while preserving the original design and statistical properties of the data to the highest degree possible. Specifically, each year primary sampling units (PSUs) are randomly selected for combination or division and original strata may be combined with adjacent strata. Self-representing PSUs may be treated as non self-representing as a result of this process. Case weight, replicate, and PSU frame count values are adjusted to reflect changes to PSUs and strata and to further maximize disclosure protection.
PSU and strata identification values are randomized each year. While DAWN is not designed to identify the contribution or influence of a particular hospital, applied disclosure protection methods and identification value randomization preclude multi-level modeling at the hospital-level and comparison of individual sampling units over time.
While disclosure protection has been applied to minimize deviance from the original sampling error calculation model, statistical analyses generated from the public use file may vary from results provided on the DAWN Web site. For online analysis using Survey Documentation and Analysis (SDA), complex design variables are used to generate statistical results, but are not directly accessible. Therefore, SDA utilizes original design variables modified slightly to accommodate the variance estimation capabilities of the SDA statistical program.
Original variables recoded for disclosure protection include:
Quarter: Month of episode has been recoded into quarter.
Day part: Exact time of episode has been recoded into four day part categories.
Case disposition: "Chemical dependency/detox" has been combined with "Psychiatric unit". Hospitals with combined chemical dependency and psychiatric units are included in the "Other inpatient unit" disposition category.
For 2005, 224 hospitals submitted data that were used for estimation. The overall weighted response rate was 28.9 percent. For the 12 oversampled metropolitan areas and divisions, the individual response rates ranged from 31.1 percent in the Houston metropolitan area to 77.3 percent in the Detroit metropolitan area.
DAWN cases are found through a review of ED medical records in participating hospitals. Across all participating hospitals in 2005, 11.5 million charts were reviewed to find the drug-related ED visits that met the DAWN case criteria. On the basis of the review of charts, 268,128 drug-related visits were found and submitted to the DAWN database, a case rate of 3.3 percent. On average, a DAWN member hospital submitted 843 DAWN cases. However, the number of submitted cases varied widely across hospitals, from less than 50 cases to over 9,000 cases in a single hospital during 2006.
Terms of use are available at http://www.icpsr.umich.edu/icpsrweb/ICPSR/studies/33042/terms
AVAILABLE. This study is freely available to the general public.