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Strengthening the Data Infrastructure for Outcomes Research on Mortality Associated with Opioid Poisonings

Modernizing the Infrastructure for Capturing Drug Death Data and Enhancing Research on Opioid Poisoning Using Death Certificates
  • Centers for Disease Control and Prevention (CDC)
Start Date
  • 5/1/2018
  • Use of Clinical Data for Current Research
  • Linking of Clinical and Other Data for Research


STATUS: Completed Project


Cause of death information from death certificate data is often used by researchers and those in public health for programmatic, policy, and PCOR research needs. This project redesigned and enhanced the Vital Statistics Rapid Release (VSRR) and Medical Mortality Data System (MMDS), both subsets of the National Vital Statistics System (NVSS), to improve the quality of death information data and release. The redesign of the MMDS to code and process a larger percentage of death certificate records including deaths involving opioids improved timeliness and accuracy of data thus improving the quality of data available to researchers. The enhancement of the VSSR captured a broader array of geographic and demographic data in records.

The MMDS codes all death records in the United States. Developed in the 1980s, it uses algorithms to assign underlying cause of death, multiple cause of death, and other fields using data inputs from the medical and demographic portions of the death certificate. The literal text portion of the death certificate contains information about drugs that caused or contributed to death. Software developed by the National Center for Health Statistics (NCHS) and the Food and Drug Administration (FDA) was used as an enhanced prototype to strengthen the MMDS coding process through collaboration with the National Library of Medicine (NLM). The enhancements identified drug information found in the literal text field, assigned the literal text data to drug vocabularies and classifications used in the research community, and included the coded supplemental information in NVSS’ restricted-use multiple cause of death mortality files (NVSS-M) and the National Death Index (NDI).

The VSRR Program supports drug overdose death surveillance through quarterly estimates of national death rates for leading causes of death and monthly counts of drug overdose deaths by state for a limited set of drugs identifiable from ICD-10 codes. The data system used to produce VSRR reports was enhanced to include geographic, demographic, and drug details in the death, information that was not previously captured by provisional monthly and quarterly releases, as well as to automate the production of standard and ad hoc VSRR reports.


The overall goal of this project was to strengthen mortality data infrastructure for outcomes research on deaths associated with opioid poisoning. This project laid the foundation for research on other causes of death in the future.

Project Objectives:

  • Redesign the MMDS to electronically code and incorporate specific drug information captured in the literal text fields of death certificate records.

  • Incorporate supplemental drug information from the literal text fields of death certificate records, especially information related to deaths involving opioids, as new variables in the NDI and the NVSS’ restricted-use multiple cause of death mortality files (NVSS-M).

  • Annually produce the NDI and the NVSS-M data files containing the supplemental information for deaths involving drugs such as opioids for use by approved researchers.

  • Improve the specificity of drug information on death certificates supplied by states by developing and pilot testing a Fast Healthcare Interoperability Resources (FHIR®) application programming interface (API) for the exchange of information from between medical examiner and coroner case management systems and state Electronic Death Registration System (EDRS).

  • Improve the depth and timeliness of national reporting on drug deaths involving opioids by re-architecting the data system to produce and release more in-depth information about drug overdose data (e.g., specific drugs, demographic information) on a monthly basis for public health surveillance and research.

  • Establish an advisory committee of the NCHS Board of Scientific Advisors to align changes in the mortality data system with end users’ (i.e., researchers’) needs.


  • The project team developed and implemented the new coding system, MedCoder, to replace the existing MMDS, and conducted an evaluation to identify gaps and areas of improvement in MedCoder. Based on the evaluation, the team adjusted the coding rules for capturing information from death certificates to better identify drugs involved in deaths.

  • The team used MedCoder, which leverages natural language processing and machine learning algorithms, to capture information from literal text fields on death certificates and create new variables on opioid-involved deaths. These variables were added to NDI and NVSS-M 2021 datasets.

  • The team expanded the VSRR program reports and developed public, web-based dashboards on monthly provisional drug overdose death counts and quarterly provisional estimates of national death rates.

  • The project team successfully developed and piloted a FHIR® API for the exchange of mortality data between states’ EDRS and medical examiner/coroner offices. The FHIR® application is currently in use by Georgia and Washington, D.C.

  • The team established an advisory committee to ensure that the design of system improvements throughout the project aligned with end-user’s needs in studying drug overdose deaths involving opioids.



  • The project team published the Vital Records Death Reporting (VRDR) FHIR® Implementation Guide that describes interoperability enhancements to allow for exchange of data between medical examiner/coroner offices and EDRS. The guide is available here:

  • The team published the NVSS Modernization Tool Kit, which helps jurisdictions and technical partners utilize modernized NVSS tools. The toolkit is available here:

  • The team developed the Vital Statistics Rapid Release Quarterly Provisional Estimates Dashboard, which includes crude and age-adjusted death rate quarterly data in all states. The dashboard is located here:

  • The team developed the Provisional Drug Overdose Death Counts Dashboard that illustrates national and state-level monthly provisional counts for drug overdose deaths based on NVSS mortality data. The dashboard is available here:


  • The team published a letter, “Association of Medical Stimulants with Mortality in the U.S. From 2010 to 2017,” in JAMA Internal Medicine. The publication is available here:

  • The project team published a National Health Statistics Report, “Opioid-involved Emergency Department Visits in the National Hospital Care Survey (NHCS) and the National Hospital Ambulatory Medical Care Survey.” The report is available here:

  • The project published a Vital Statistics Rapid Release Report, “Timeliness of Death Certificate Data by Sex, Age, and Geography,” that discusses the timeliness of death mortality data from the NVSS. The report is available here:

  • The team published a National Vital Statistics Report, “Drug Overdose Deaths Involving Fentanyl, 2011–2016,” which describes trends in drug overdose deaths involving fentanyl. The report is available here:

  • The project team published a National Health Statistics Report, “Drug-involved Infant Deaths in the United States, 2015–2017,” that describes drug-involved infant deaths by type of drug and select maternal and infant characteristics. The report is available here:


Below is a list of ASPE-funded PCORTF projects that are related to this project

Enhancing Data Resources for Researching Patterns of Mortality in Patient Centered Outcomes Research – Through collaboration between the Centers for Disease Control (CDC), Centers for Medicare and Medicaid (CMS), and Food and Drug Administration (FDA), the overall goal of this project is to increase the availability of information on the cause of death by linking NDI data to other sources. Enabling linkages will allow researchers to develop national estimates of cause-specific death rates following emergency department visits and/or hospital stays for specific conditions.

Improving the Mortality Data Infrastructure for Patient-Centered Outcomes – Comprised of all U.S. mortality events since 1979, the NDI database allows researchers to match entries in the NDI to those participating in longitudinal clinical and epidemiologic studies to determine both fact and cause of death. A significant challenge with the NDI has been the lag between the date of death and the availability of the record for matching purposes. The CDC’s NCHS worked to improve the infrastructure to support more timely and complete mortality data collection through more timely delivery of state death records (e.g., cause of death) to the NDI database and through linking NDI records with nationally collected hospital datasets to obtain a more complete picture of patient care.