Social and Behavioral Theories

4. Important Theories and Their Key Constructs

Transtheoretical Model/Stages of Change

Long-term changes in health behavior involve multiple actions and adaptations over time. Some people may not be ready to attempt changes, while others may have already begun implementing changes in their smoking, diet, activity levels, and so on. The construct of “stage of change” is a key element of The Transtheoretical Model (TTM) of behavior change, and proposes that people are at different stages of readiness to adopt healthful behaviors. The notion of readiness to change, or stage of change, has been examined in health behavior research and found useful in explaining and predicting changes for a variety of behaviors including smoking, physical activity, and eating habits. The TTM has also been applied in many settings.

Figure 2

Transtheoretical Model/Stages of Change

An illustration of the Transtheoretical Model/Stages of Change.

Source: Prochaska, J. O. & Di Clemente, C. C., (1982). Transtheoretical therapy: Toward a more integrative model of change. Psychotherapy: Theory, Research and Practice, 19(3), 276-288. Figure 2, p. 283.