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The Shameful Power of a Theory of Change

Stages of Change is is a concept deeply embedded in our thinking about health behaviors and obesity. “How ready are you to change?” is the core question. But when applied to obesity care, it is a model with shameful power to promote implicit bias. A new perspective today in the New England Journal of Medicine illustrates how the concept can go terribly wrong. That’s because it often means failure in obesity care is the patient’s fault. Scott Hagen writes:

“Weight reduction, the description suggests (and many clinicians assume), is as simple as adopting permanent caloric restriction, and the failure of a person with obesity to achieve and maintain weight loss is caused by a lack of discipline.

“At every turn in my patient’s experience with the healthcare system, well-intentioned clinicians would subject him to this idea.”

Thus, he aptly labels this our culture of shame in medical care. His patient tells Hagen he’s “been bad,” declines treatment, and resolves to do better on his own. This is a patient with a long history of obesity that resists all his efforts to manage it himself. So it is keeping him from getting a knee replacement he needs.

Troubles with the Transtheoretical Model

Transtheoretical Model, Stages of ChangeAnother name for Stages of Change is the transtheoretical model of behavior change. In fact, the stages of change is just one element of that model. Christopher Armitage writes:

“The transtheoretical model is arguably the dominant model of health behaviour change, having received unprecedented research attention, yet it has simultaneously attracted exceptional criticism.”

A 2011 Cochrane Review found no conclusive evidence for sustainable weight loss from using this model. That did not sit well with fans of this model, so a revision in 2014 found very low quality evidence that it might lead to better dietary and physical activity habits. This falls short of faint praise.

Robert West writes:

“When it comes to assessing motivation to change, it would be better to revert to simple questions about desire to change that were in place before the SOC model was developed.”

Motivational interviewing is a framework that allows clinicians to meet patients where they are, without judging their readiness – which can be a surrogate for worthiness.

Fixated on Behavior over Biology

Ultimately, the problem with stages of change is how it fits so neatly with a bias that obesity is a simple behavioral problem. If someone can’t overcome obesity, it’s just because they’re not ready to change. That’s the flawed thinking that burrows so easily into our brains.

We need fundamental changes to overcome this and health professionals should lead it. Hagan describes the necessary change perfectly:

“To fight weight bias and to expand the study and use of effective weight-loss therapies, the health professions need to transform themselves from adversaries of patients with obesity to allies.”

Click here for Hagan’s excellent commentary in NEJM.

Female Head, painting by Pablo Picasso / WikiArt

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December 16, 2021

5 Responses to “The Shameful Power of a Theory of Change”

  1. December 16, 2021 at 7:23 am, Al Lewis said:

    This was the go-to for the wellness industry for two decades. Showed massive savings. They also urged employees to eat more carbs and less fat. Showed massive savings.

    Basically no matter how stupid their intervention, they showed massive savings. Their “secret sauce”? Lying.

  2. December 16, 2021 at 3:29 pm, John Dixon said:

    Motivational interviewing and readiness to change imply the need to change (we all know what had to change)! It’s called blaming and shaming.

    Who needs to change? We should look in the mirror. We need to change our approach to managing this disease like we approach other disease. As health care professionals we need rethink our approach?

    Why do we treat this disease like no other?

  3. December 16, 2021 at 7:39 pm, Patrick M. O'Neil said:

    In addition to the important points here about blaming patients for their obesity, there is no telling how much the “stages of change” model and related notions have held back the development of behavioral interventions for obesity and other health conditions, by using time, effort and funding that could have been put to much more productive use.

    Here is the entirety of the contributions of the model: People are unlikely to do things they are not ready to do.

    And if a patient with obesity admits he or she is not ready to take on some of the very difficult challenges asked of them in our current weight control interventions, perhaps the best responses are a) appreciation of their candor and b) a follow-up question: are there less challenging changes that you might be ready to try?

    • December 17, 2021 at 4:20 am, Ted said:

      Thank you for a wise summary, Patrick.

  4. December 24, 2021 at 11:24 am, karen r koenig said:

    It’s the food industry & our culture that need to change. Great book on that subject: A book review by Karen R. Koenig: Why Smart People Make Bad Food Choices: The Invisible Influences that Guide Our Thinking