The current findings must be interpreted with caution in light of several limitations. First, we studied mandated students and did not have a true no-treatment control group (because of ethical considerations and program requirements). This restriction most likely decreased our power to detect stronger intervention effects, although our effect sizes were comparable to other studies on mandated and volunteer students (see Carey, Scott-Sheldon, et al., 2007; Larimer & Cronce, 2007) (see also Barnett & Read, 2005 for likely reasons). In addition, the absence of a true control group prohibited us from attributing change to a PFI. Thus, we interpreted individual and situational factors as the predictors of change in the context of a PFI.
