The National Crime Victimization Survey (NCVS) is an annual survey that collects data on crime against persons aged
12 years or older from a nationally representative, stratified, multistage cluster sample of United States households. Since 1999, the
Police-Public Contact Survey (PPCS) has been administered every 3 years as a supplemental survey to all persons aged 16 years or older within households sampled for the NCVS.
The United States Census Bureau fielded the 2008 PPCS questionnaire, processed the survey data, and provided estimation specifications. The 2008 PPCS was pretested in the spring of 2008 and conducted between July 1, 2008, and December 31, 2008. Respondents were asked about their contacts with police during the past 12 months. For instance, persons interviewed in July 2008 were asked about contacts that occurred between August 2007 and July 2008. Those interviewed in August 2008 were asked about contacts between September 2007 and August 2008.
In 2008 the PPCS interviewed 57,978 of the 72,566 eligible individuals in the NCVS sample. A total of 14,588 nonrespondents who were excluded from the 2008 PPCS as non-interviews or as proxy interviews. Non-interviews (12,803) included respondents not available for the interview, those who refused to participate, and non-English speaking respondents. (Unlike the NCVS interviews, PPCS interviews are conducted only in English.) The remaining 1,785 were proxy interviews representing household members who were unable to participate for physical, mental, or other reasons. After adjustment for nonresponse, the sample cases in 2008 were weighted to produce a national population estimate of 236,511,832 persons aged 16 years or older.
Stratified multistage cluster sample.
Respondents aged 16 years and older to the National Crime Victimization Survey during the last six months
of 2008. The universe of the NCVS is all persons in the United States aged 12 years and older.