Drug Involved Mortality Restricted Variable

The Drug-Involved Mortality (DIM) data enriches the National Vital Statistics System, Mortality (NVSS-M) data system with information on substances, as well as prescription (using generic names only – no trademarks) and illicit drugs mentioned on death certificates of residents of the United States and the District of Columbia.  The DIM contains a list of codes from the Tenth Revision of the International Classification of Diseases (ICD-10) and can be combined with demographic and geographic characteristics.

Predetermined restricted variables for the 2010-2017 NVSS DIM data files were created by examining the literal text of three fields on the death certificate:  Part I-Cause of Death, Part II –Significant Conditions Contributing to Death and Box 43, a verbatim description of how the injury occurred. The DIM data system does not support individual examination of “literal text” and the actual variables showing free-form text are not included in these files.

For every year of data, there are three linkable SAS datasets:

  1. A demographics file with a single record for every death of a U.S. resident of the 50 U.S. States and the District of Columbia, and includes demographic, geographic, and cause-of-death variables from the NVSS-M mortality files.
  2. A mention-level file with each record pertaining to a substance mention that was identified in death certificate literal text. Typical variables consist of “yes/no” flags.  The drugs and substances flagged correspond to a search term list (not available) that was developed in collaboration with staff from the Food and Drug Administration (FDA).
  3. A decedent-level file that contains a single record for each decedent with at least one substance mention in death certificate literal text, and that quantifies the number of mentions of involvement of each substance in death. Substances were identified in literal text using search terms and were classified by level of specificity of information (e.g., specific substances, classes of drugs or substances, or non-specific substances (i.e., exposure not otherwise specified)).

The demographic, decedent-level, and mention-level files, are linkable by use of the decedent_ID variable, which is unique within each year.

There are different versions of the decedent-level and mention-level files.  Each version is organized by the date when the literal data were processed to identify substance-involved mortality.  Search terms and the words and phrases used to ascertain the context in which the substances were mentioned are enhanced with each new version.  The content of the demographics file does not change across data versions.

Use of the most recent version is encouraged for all analyses, including analyses intended to replicate or extend prior analyses.  Older versions can be used to replicate previous analyses and to extend those analyses using different data years. Because the most recent version is the most enhanced, use of older versions for de novo analyses is discouraged.

DIM Documentation  [PDF – 333 KB]

Data Request
Prospective researchers must request the DIM documentation before submitting a proposal to the RDC. In your request include research question, abstract, and DIM files with years.  Submit all request to rdca@cdc.gov

Researchers must identify demographic variables to include in your proposal. The RDC Analyst will only provide the variables listed in the proposal.  Note, you provide justification for each demographic variable requested.