State-Level | NFLIS-Drug Counts: Data Terms


Census Region: The four regions of the United States as defined by the U.S. Census Bureau are:

  • Northeast Region: Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont
  • Midwest Region: Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin
  • South Region: Alabama, Arkansas, Delaware, District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, and West Virginia
  • West Region: Alaska, Arizona, California, Colorado, Hawaii, Idaho, Montana, Nevada, New Mexico, Oregon, Utah, Washington, and Wyoming

Data Run Date: NFLIS-Drug report counts are subject to change; “the NFLIS-Drug database is dynamic—even across years—and queries of the data may result in updated drug counts for more recent years. Therefore, it is important to note the date on which the data were generated because it underscores the reality that these tables reflect a snapshot in time and may not be comparable with data queries generated on a different date.”1 The specific dates each State’s data were run are noted in the source section or hover boxes in the visualization.

Drug Rank: Based on the number of drug reports. In a tie (i.e., two or more drugs have the same number of reports), drugs are assigned the same ranking and a gap is left in the ranking numbers. Each item is assigned a rank equal to the number of items ranked above it plus one.

Drug Report: Drug that is identified in law enforcement items, submitted to and analyzed by State or local forensic labs and included in the NFLIS database. “Drug cases secured in law enforcement operations (i.e., drug seizures) are submitted to forensic laboratories for analysis. An individual drug case can vary in size, and one case can consist of one or more drug items. Within each item, multiple drugs may be identified and reported. A single report equates to one documented occurrence of a drug. Each report is counted separately and added to the NFLIS-Drug data.”1 The data presented in these data visualizations are based on the top three drug reports per item submitted for analysis.

Drug Report Count: For each State, the NFLIS drug reports are based on actual reported data or counts rather than estimates of submissions of items seized in the site’s catchment area. DEA does not recommend comparing year-to-year trends using raw counts from NFLIS-Drug published tables.1 The differences in counts may be more reflective of differences in laboratory reporting for that time frame rather than changes in drug abuse or trafficking.1 The data represent a snapshot of the NFLIS-Drug database as of the date the data were run.

Drug Report Estimate (data not presented in these visualizations): National and regional estimates are the statistically adjusted number of reports that account for nonreporting and nonsampled laboratories and allow for inferences to be made of the total number of analyzed drug reports in the entire NFLIS-Drug “universe” of State and local forensic drug laboratories.1 Estimates are not available for States; however, national and regional estimates are available from the Drug Enforcement Administration (DEA) in mid-year and annual reports at:

National Drug Early Warning System (NDEWS): NIDA-supported project that monitors emerging drug use trends to enable health experts, researchers, and concerned citizens across the country to respond quickly to potential outbreaks of illicit drugs such as heroin and to identify increased use of designer synthetic compounds. The Center for Substance Abuse Research (CESAR) at the University of Maryland serves as the NDEWS Coordinating Center and is the author of these NFLIS visualizations.

NFLIS-Drug: National Forensic Laboratory Information System, a DEA program that systematically collects results from drug analyses conducted by participating Federal, State and local forensic laboratories. These laboratories analyze controlled and non-controlled substances secured in law enforcement operations across the United States.

Drug Categories: Drugs/substances comprising Fentanyl-related substances, Synthetic Cannabinoids, and Synthetic Cathinones were pulled from NFLIS-Drug public use data tables, Table 3: State Counts for Fentanyl and Fentanyl Related Substances, Table 4: State Counts for Synthetic Cannabinoids, and Table 5: State Counts for Synthetic Cathinones. The data tables are available at:

Note that these are not comprehensive lists of substances for each NPS category. Because of the nature of the NFLIS-Drug data, it is highly likely that some drugs or substances have not yet been seized by law enforcement and reported by NFLIS-Drug laboratories.1

Map Classifications (color-coded classification schemes used in Maps): There is no single best map classification method—we present two types that focus on different aspects of cross-state comparisons.

Quintile Classification: These displays focus attention on relative rankings. A quintile is one of five equal measurements that a set of things can be divided into. Here the States with the highest number of drug reports are in the 5th (top) quintile, the next highest set of States are in the fourth quintile, and so on to the first (bottom) quintile. Outlier drug report values may be less visible in this map classification since they are grouped with other high or low value States.

Custom Interval (DEA and NCC-defined) Classification: These displays facilitate comparing maps over time. The NCC replicated three DEA interval classification schemes (#1, #2, and #4 below) to align with maps published in DEA reports. The NCC created an additional classification scheme (#3 below) to facilitate comparisons for mid-range drug reports (i.e., drugs with more than 5,000 reports but fewer than 25,000 reports per State). The categories for each drug were held constant across years to focus on comparing maps over time.

    • 1. For drugs with fewer than 1,000 reports per State, the interval categories are:
      • 0 reports
      • 1-19 reports
      • 20-49 reports
      • 50-99 reports
      • 100+ reports
    • 2. For drugs with more than 1,000 but fewer than 5,000 reports per State, the interval categories are:
      • 0 reports
      • 1-99 reports
      • 100-299 reports
      • 300-499 reports
      • 500+ reports
    • 3. For drugs with more than 5,000 reports but fewer than 25,000 reports per State, the interval categories are:
      • 0 reports
      • 1-499 reports
      • 500-1,499 reports
      • 1,500-2,499 reports
      • 2,500+ reports
    • 4. For drugs with more than 25,000 reports per State, the interval categories are:
      • 0 reports
      • 1-2,499 reports
      • 2,500-4,999 reports
      • 5,000-9,999 reports
      • 10,000-16,999 reports
      • 17,000+ reports


1U.S. Drug Enforcement Administration (DEA), Diversion Control Division. (undated). National Forensic Laboratory Information System: NFLIS Public Resources Library, NFLIS Questions and Answers (Q&A). Retrieved from:


Revised: January 2020

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