Wednesday, March 20, 2013

Why your patient might not be following your advice: The Health Belief Model

In my last two posts, I've been sharing some introductory ideas about Health Behavior Theory (HBT).  I'd like to take things a step further today and delve a little more deeply into some specific concepts.

Let's explore one of the most well-studied health behavior theories - the Health Belief Model (HBM).

The HBM states that our health choices are a direct consequence of our perceived susceptibility to a disease, our perceived severity of a disease, and the perceived barriers that keep us from adopting better habits.

Perceived susceptibility, perceived severity, and perceived barriers are three of the main constructs from the HBM.  The word "perceived" is very important; these assumptions are based on individual perceptions and deductions based on a combination of environment, experiences, and personality.

"Perceived susceptibility" refers to how at risk we think we are to a particular disease.  In my master's thesis,* I studied the literature on adherence to high blood pressure medications.  Turns out that people who think they're not at risk to have high blood pressure (even if they really do have it) don't take their meds.

"Perceived severity" refers to how bad we think having a particular disease is.  Turns out that people who know they have high blood pressure but don't think it's a particularly dangerous condition (they don't know, for example, that high blood pressure can lead to heart attacks, strokes, or kidney failure) don't take their meds.

"Perceived barriers" almost always boils down to one of three obstacles: not having enough money, not having enough time, or not having enough social support.  If people can't afford their high blood pressure medication, they're not going to take it.  If they don't think they have the time to exercise, they won't.  If the foods we tell them to eat are different from the food their friends and family eat, they probably won't eat them.

Identifying which of these constructs is at play when a patient isn't following our advice is key to improving adherence with our recommendations. Doctors and health professionals can help patients change their perceptions, and thereby change their attitudes about treatment - but only if we've taken the time to identify what is making it hard for our patients to follow our advice.

We can do this by being careful listeners and asking thoughtful questions.
   "What kind of person do you think gets high blood pressure?" (perceived susceptibility)
   "What kinds of problems can result from high blood pressure?" (perceived severity)
   "What has made it hard for you to take your medicine?" (perceived barriers)
These  questions can uncover if an HBM construct is at play. Only after identifying and validating** our patients' beliefs and attitudes can we gently correct incorrect assumptions, supply additional knowledge, and/or problem-solve with our patients.

"Because I said so" doesn't work with patients, but exploring their beliefs and attitudes about disease and treatment can go a long way toward helping them to improve their health.

* Here's a summary of my master's thesis that was published in 2009 if you're interested:
(I focused on African Americans since I was primarily serving an African-American neighborhood  in my prior job.  I did a subsequent unpublished literature review that showed the same concepts basically hold for most white patients.)

** As the residents I teach are probably tired of hearing me say, "validating" does not equal "agreeing."  We can acknowledge to our patients that we can see how their belief makes sense to them without necessarily agreeing with the accuracy of that belief.  Patients who feel that their beliefs are unvalidated are unlikely to accept our alternative belief.


  1. Excellent points that mos tpeople do not realize until they are knee deep in the tranches. Great job.
    Marielaina Perrone DDS

  2. But even with an understanding of the above principles regarding lack of compliance, how do we change the patients perception of their own health? How do use the information we gain about them to generate change?