The conflict tactics scale (CTS), created by Murray A. Straus in 1979, is used in the research of family violence." There are two versions of the CTS; the CTS2 (an expanded and modified version of the original CTS) and the CTSPC (CTS Parent-Child). As of 2005, the CTS has been used in about 600 peer reviewed scientific or scholarly papers, including longitudinal birth-cohort studies. National surveys conducted in the USA include two National Family Violence Surveys (1975 and 1985), the National Violence Against Women Survey (1998), which, according to Straus, used a "feminist version" of the CTS in order to minimize data on female perpetration of intimate partner violence (IPV), and the National Survey of Child and Adolescent Well-Being. A major international survey to use the CTS was the 2006 International Dating Violence Study, which investigated IPV amongst 13,601 college students across thirty-two different countries.