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  1. Describe the relationship between terms used to define medication adherence including persistence, compliance, adherence, and concordance.

  2. List appropriate responses in dealing with potential adherence problems.

  3. Discuss the methods to measure adherence including limitations.

  4. Describe common misconceptions about medication adherence.

  5. List eight common adherence risk factors.

  6. Describe behavioral interventions to improve adherence.




Medication nonadherence is a major public health problem. Nearly half of the 187 million people who take medications in the U.S. do not take them as prescribed. Poor medication adherence costs over $100 million annually. Patients with poor adherence to diabetes medication cost the health care system twice as much as patients with high adherence. While adherence to medication is a problem, adherence to diet and exercise, and other therapeutic modalities is even less than for medications. There is great confusion about what medication nonadherence is. Are you nonadherent if you miss or are late for any dose? Or are you considered adherent if you take 80% or more of your medication? Every study or review article uses different definitions. There is also confusing terminology. Compliance was the original term, but was considered to be politically incorrect by some because it implied following the providers’ orders. Adherence came next because it is more politically correct than compliance and is the current “in” term in the United States. Persistence refers to how many pills are picked up from the pharmacy and is more of an economically focused term. Finally, experts in the United Kingdom thought that adherence was as bad as compliance and used concordance to better represent that the patient was in partnership with their provider and worked closely together to optimize patient outcomes. Finally, we have classified medication adherence into two categories: intentional and nonintentional (Table 5.1). This classification has some utility because it does generally relate to potential interventions to improve medication adherence.

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Types of Nonadherence




There are numerous misconceptions about medication adherence among health care providers. The major misconception is that they “manage” a patient’s chronic disease. In reality, the only time a health care provider manages a chronic disease is the 15 to 30 minutes during periodic follow-up visits. The remainder of the time the patient manages their chronic disease. One expert said that providers need to recognize “whose disease is it ...

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