National Drug Threat Survey Methodology

Administering the NDTS includes designing the survey instrument (questionnaire), designing a survey sample, administering the survey, and deriving national, regional, and state statistical estimates from the data obtained through the survey.

Survey Instrument

The NDTS questionnaire is designed by NDIC and is approved by the Office of Management and Budget (OMB) for use in collecting data from public law enforcement agencies (OMB Number 1105-0071).  More...

Sample Design

The NDTS sample was drawn in 2003 from the 2000 Census of State and Local Law Enforcement Agencies conducted by the U.S. Bureau of Justice Statistics.   After careful review of the more than 17,000 law enforcement agencies in the 2000 Census of State and Local Law Enforcement Agencies, a final sample frame of 7,930 state and local law enforcement agencies with drug law enforcement responsibilities was created.  More...

Survey Administration

A point of contact at each law enforcement agency in the NDTS sample is verified by NDIC personnel to ensure the survey is directed to persons familiar with the drug trafficking situation in the agency’s area of responsibility.  More...

Estimation Techniques

All agencies in the sample are weighted to sum to the population of the sampling frame.  More...