Measuring processes of change: applications to the cessation of smoking.

Subjects (A' = 970) representing five stages of smoking cessation (precontemplation, contemplation, action, maintenance, and relapse) were given a 65-item test measuring 10 basic processes of change. Subjects recorded the last time they quit smoking, their current use, the frequency of occurrence, and the degree of item helpfulness. A 40-item questionnaire provided highly reliable measures of 10 processes of change, labeled (a)consciousness raising, (b) dramatic relief, (c) self-liberation, (d)social liberation, (e) counterconditioning, (f) stimulus control, (g) self-reevaluation, (h) environmental reevaluation, (i) reinforcement management, and (j) helping relationship. In a confirmatory analysis, 770 subjects were assessed 6 months later. The analysis both confirmed the 10-process model and revealed two secondary factors, Experiential and Behavioral, which were composed of 5 processes each and reflected hou. individuals in particular stages use more lhan I process at a time. The transtheoretical model of change and available external validity evidence are reviewed.