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Methods and Practices

LAPOP: Methods and Practices

Each country survey is implemented based on a national probability design. In some cases, oversamples are collected to allow precise analysis of opinion within sub-national regions. Survey participants are voting-age adults interviewed face to face in their households, except in Canada and the United States where the interviews are Web-based.

Cutting-edge methods and transparent practices ensure that data collected by LAPOP are of the highest quality. These methods and practices include the following:


  • Solicitation of input from a vast network of academics, practitioners, and policymakers
  • Use of Vanderbilt University's experimental research lab to test new items
  • Extensive in-country pre-testing of survey items
  • Translation of surveys into several languages in the Americas
  • Expert design of national probability samples
  • Approval of Vanderbilt University's Institutional Review Board for the protection of human subjects


  • Rigorous training of all interviewers using guidelines published in detailed training manuals
  • Partnerships with reputable survey organizations in the region
  • Widespread use of electronic handheld devices and specialized software by LAPOP to allow multilingual interviews and extensive validity checks


  • Use of cutting-edge statistical programs and methods to audit, process, and analyze the data sets
  • Clear, user-friendly graphs featured in reports
  • Public dissemination in surveyed countries
  • Uploading of data onto LAPOP's website and into LAPOP's free interactive data analysis program