Medication Adherence Report Scale (MARS)™

The MARS™ measures self reported adherence to medicines, it assesses both intentional and unintentional non-adherence.

Where can it be used?

The MARS™ was originally validated within asthma in which studies supported both it’s reliability and validity. There have been subsequent studies in chronic illness samples including:


It provides a ‘spot check’ estimate of a patient’s adherence behaviour, it can also be used within exploratory studies to identify a cohort of patients with low adherence. Another use for the MARS™ is to evaluate the impact of interventions. It is available in a variety of languages.

How does it work?

The MARS™ measures adherence in a non-threatening manner to minimize social pressure which leads to under reporting of non-adherence. Respondents indicate their agreement with statements about their medicine use on a 5 point Likert scale.

To find out more about using the MARS in your work please contact Professor Rob Horne.