“…Those that have been shown to make a significant difference in response rates include the use of incentives (Bosnjak & Tuten, 2003;Church, 1993;Dillman, 2007;Heerwegh, 2006), increasing the number of contacts with participants (Klofstad, Boulianne, & Basson, 2008;Dillman, 2007); personalization of invitations (Dillman, 2007;Heerwegh & Loosveldt, 2007;Heerwegh, Vanhove, Matthijs & Loosveldt, 2005;Joinson, Woodley, & Reips, 2007), and well-crafted invitation messages, which includes the trustworthiness of the sender (Porter & Whitcomb, 2005;Trouteaud, 2004;Tuten, 1997). However, none of these interventions, by itself, trumps the others with regard to effectiveness, and conflicting reports of effectiveness exist.…”