Adherence to medication

Adherence, compliance and concordance are all terms used to describe how patients take medicines. Although they are still often used interchangeably there are important differences.

• Compliance. Until recently, this was the most common term used to describe the extent to which a patient's behaviour matches the prescriber's recommendations. It has been widely criticised because it carries negative connotations about the relationship between prescribers and their patients. It implies a relationship where the prescriber decides on the appropriate treatment, issues the relevant instructions, leaving the patient to passively comply. Non-compliance might then be interpreted as inappropriate, disobedient or even incompetent.
• Adherence. The term adherence has been adopted as a preferred alternative to compliance. It is attempts to emphasise that the patient is free to decide whether to follow the prescriber's recommendations and that failure to do so should not be a reason to blame the patient. Adherence augments the definition of compliance by including an emphasis on the need for patient agreement about the most appropriate medication regimen.
• Concordance. Concordance is a term that encapsulates the idea that 'the consultation is a negotiation between equals and that therefore the aim is a therapeutic alliance between them'.