The research project “Studies onTrajectories of Adolescent Relationships and Sexuality” (“Project STARS”) is a four-wave longitudinal study of 1,297 adolescents from the Netherlands. The study was conducted by Utrecht University, in cooperation with the University of Groningen.

Project STARS was the first longitudinal study to combine both normative and risk oriented perspectives on adolescent sexual development. It was unique in its design; including four sub-projects (PhD projects) that each addressed a specific domain that plays a role in sexual development. Project 1 focused on individual characteristics (Baams, 2015). Project 2 investigated the role of parents and peers in adolescent sexual development (Van de Bongardt, 2015). Project 3 focused on both receptive and interactive sex-related online behaviors in relation to adolescents’ sexual development, as well as the personal and socio-contextual conditions in which these relations are embedded (Doornwaard, 2015). In addition to these three doctoral dissertations, a fourth dissertation was written at the University of Groningen, on daily diary data (Dalenberg, 2017). These data are not part of the present DANS-dataset.