“…The significance of this gap in the addictions literature is highlighted by recent studies suggesting that 7% to 17% of school-based youth require treatment for psychoactive substance use disorders (SUDs; Harrison, Fulkerson, & Beebe, 1998;Hartwell, Ungemack, & Babor, 1996). Studies suggest that a range of treatment approaches, including 12-Step, cognitive-behavioral, and family-based interventions, work for drug-abusing youth (Kaminer, Burleson, Blitz, Sussman, & Rounsaville, 1998;Latimer, Newcomb, Winters, & Stinchfield, 2000;Surgeon General, 1988;Winters, Latimer, & Stinchfield, 1999). However, sample size limitations characterizing extant studies have generally precluded a thorough examination of factors that explain why treatments work for some but not for others (Catalano, Hawkins, Wells, & Miller, 1991;Winters, 1999).…”