Validation of the Short Version (TLS-15) of the Triangular Love Scale (TLS-45) across 37 Languages

Love is a worldwide known phenomenon that affects many aspects of human life, including considering a romantic partner with whom to bond. Thus, developing a reliable and valid measure of love experiences is crucial. One of the most popular tools to test love levels is Sternberg's 45-item Triangular Love Scale (TLS-45), which measures three love components: Intimacy, Passion, and Commitment. However, our literature review reveals that the majority of studies (64%) use a broad variety of shortened versions of the TLS-45. To achieve scientific consensus and improve the reliability, comparability, and generalizability of results across studies, here, we develop a short version of the scale–the TLS-15–which contains 15 items with a 5-point rather than 9-point response scale. In Study 1 (N = 7,332), we re-analyzed secondary data from a large-scale multinational study that validated the original TLS-45 to establish whether the scale could be truncated. In Study 2 (N = 307), we provided evidence for the three-factor structure of the TLS-15 and its reliability. Study 3 (N = 413) confirmed convergent validity and test-retest stability of the TLS-15. Study 4 (N = 60,311) presented a large-scale validation across 37 linguistic versions of the TLS-15 on a cross-cultural sample spanning every continent of the globe. The overall results provided support for the reliability, validity, and cross-cultural invariance of the TLS-15, which could be used as a measure of love components–separately or jointly as a three-factor measure.