Four items measure the degree to which a person is self-reliant and values personal uniqueness without necessarily regarding themselves as superior to others. This represents the horizontal individualism dimension of the four-part individualism–collectivism framework. Triandis and Gelfand (1998) modified items from Singelis et al. (1995) and validated the scale in a factor analysis alongside horizontal collectivism, vertical individualism, and vertical collectivism items. Applied in marketing research by Kitirattarkarn, Araujo, and Neijens (2019) across four countries (U.S., Netherlands, Korea, Thailand) and by Lou, Tse, and Lwin (2019) across U.S. and Singaporean samples.
Triandis, H. C., & Gelfand, M. J. (1998). Converging measurement of horizontal and vertical individualism and collectivism. Journal of Personality and Social Psychology, 74(1), 118–128.
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