The Intrinsic Motivation Inventory (IMI) is a multidimensional measurement device intended to assess participants' subjective experience related to a target activity in laboratory experiments. It has been used in several experiments related to intrinsic motivation and self-regulation (e.g., Ryan, 1982; Ryan, Mims & Koestner, 1983; Plant & Ryan, 1985; Ryan, Connell, & Plant, 1990; Ryan, Koestner & Deci, 1991; Deci, Eghrari, Patrick, & Leone, 1994). The instrument assesses participants' interest/enjoyment, perceived competence, effort, value/usefulness, felt pressure and tension, and perceived

The Perceived Competence Scale (PCS) is a short, 4-item questionnaire, and it assesses participants' feelings of competence about, say, taking a particular college course, engaging in a healthier behavior, participating in a physical activity regularly, or following through on some commitment. Because the PCS pertains to particular behaviors or behavioral domains, it can be easily adapted to study additional behaviors or behavioral domains. The selfdeterminationtheory.org website provides two versions of the PCS conerning the feelings of being able to stick with a treatment regimen and the