“…One likely reason for this is the lack of an adequate description of the process of successful and unsuccessful attempts to stop or reduce cannabis use (Klingemann et al, 2001). Although some studies have described attempts to quit cannabis among treatment seekers, as with other drugs, the large majority of attempts to change cannabis use do not involve treatment (Blanco et al, 2015) (Klingemann et al, 2001). Previous natural history studies have described how cannabis use changes over a lifetime (Kandel & Raveis, 1989; Swift, Hall, & Copeland, 2000; VonSydow et al, 2001; Aitken, DeSantis, Harford, & FeCaces, 2000; Ellingstad, Sobell, Sobell, Eickleberry, & Golden, 2006).…”