The BIS-11 has demonstrated excellent reliability and validity (Patton et al., 1995). Support for its internal consistency in individuals with eating disorders, undergraduate students, substance abuse patients, general psychiatric patients, and prison inmates is evidenced by alphas >79 (Patton et al., 1995; Steiger et al., 2000). In our sample, BIS-11 internal consistency was slightly lower (see Table 1). In addition, discriminant validity is well established, as general psychiatric and substance-abuse patients score significantly higher on the BIS-11 as compared to undergraduate students, and prison inmates score the highest of all of these groups (Patton et al., 1995).
