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Theories & Approaches

All Theories & Approaches

Stages of Change Model

by Nicole Lezin

Welcome to the Stages of Change Model! In this section, you will find the following:


When Psychologist James Prochaska, Ph.D. was a junior in college, he lost his father to the twin demons of alcoholism and depression. Throughout his illness, Dr. Prochaska's father had expressed a mistrust in psychotherapy and refused to consider it — with tragic results.

Dr. Prochaska's frustration with this missed opportunity led him to an intensive study of psychology in an effort to understand more about people like his father and how the field could be more helpful to them. But instead of answers, Dr. Prochaska's studies led only to more questions. One puzzler was that although therapy seemed to be beneficial to many people struggling with different types of problems, no one really seemed to understand why. No over-arching theory explained how people manage to change their behaviors. In fact, as Dr. Prochaska observed, there were at least 300 different approaches and explanations fragmenting the field of behavior change.

This early observation led Dr. Prochaska and his colleague, Carlo DiClemente, Ph.D., to explore the ways that people succeed in changing their behavior. Their goal was to see whether they could detect any patterns that might apply across all the different cognitive and behavioral approaches used in modern psychology. Their discovery of common stages and processes, originally gleaned from extensive interviews with people who had overcome addictions to nicotine, became known as the Transtheoretical Model — so named because it spanned so many different theories. Its popular application, highlighting the model's new understanding, is known as "Stages of Change."


What is the Transtheoretical Model (also known as Stages of Change)?

The Transtheoretical Model, or Stages of Change, is based on several key insights — really a series of "aha!" moments — that radically shifted the way that psychologists and others understand and support the process of behavior change.

The first insight is that behavior change is a process rather than an event. Before the advent of Stages of Change, it was common to assume that a few weeks of classes, support groups, and the like might lead someone to change an entrenched behavior. This was the model behind programs to address overeating, addiction to nicotine or alcohol, and a variety of other health problems affecting people's lives.

This older approach has several implications. One is that every smoker, every person trying to lose weight, and every alcoholic will react similarly to new information and guidance. If we help someone realize there's a problem, this older model suggests, they will "see the light" and change their ways. If they don't, it's not our fault or our program's fault — it's because they lack motivation and willpower.

Prochaska's and DiClemente's insight was that the behavior change process unfolds over months and years and is characterized by six distinct stages: the Stages of Change. Each change, described in more detail in the next section, corresponds to an individual's readiness to change, which will vary over time. By matching an intervention to the appropriate stage (or readiness), program designers can improve their chances of success. Success, moreover, is defined not just by changing the behavior but by any movement toward change, such as a shift from one stage of readiness to another.

Another important and innovative contribution of Stages of Change is its emphasis on maintaining change. The model recognizes that relapse is common. For example, many smokers have to make several attempts before they quit for good. But instead of viewing relapse as a failure (i.e., the behavior change didn't last), the Stages of Change model sees relapse as an opportunity to learn how to sustain change more effectively in the future.

For example, if your first attempt at quitting smoking didn't work (as is often the case), what can you learn from your relapse? What were the situations that made it most difficult to stick to your resolve to quit — such as stress, restaurants or bars, or social situations? What can you do differently next time to increase your chances of success (e.g., making clear to friends that you are serious about quitting and need their help, or avoiding situations that may be tempting)? With relapse and learning built into the model, the process is more like an upward spiral, steadily moving toward behavior change, than a straight line.

The next section describes the model's key components: stages of change, processes, pros and cons, self-efficacy, and temptation.


Next: Key Components of the Stages of Change Model >>

Nicole Lezin, a technical writer based in Aptos, California, consults regularly with ETR Associates. Ms. Lezin has researched and written about many different aspects of public health and is the co-author, with Marshall Kreuter, Matt Kreuter, and Larry Green, of Community Health Promotion Ideas that Work: A Field-book for Practitioners.