Factorial invariance and internal consistency for the decisional balance inventory--short form.

A crucial assumption for a measure is that it is factorially invariant; that is, the measurement model is the same in different subgroups and across different occasions. The invariance of the short form of the decisional balance inventory was investigated using data from a representative sample of smokers (N=4144). Separate analyses evaluated the invariance across two levels of gender (male and female), four levels of education (grade school, high school, college, and graduate school), two levels of race (white and black), four levels of age (18-25, 26-35, 36-50, and 50+), and across four assessment occasions. The results indicated that the decisional balance inventory demonstrated strong factorial invariance across the four demographic variables and across assessments.