Self-reported adherence to statins
The MARS-5 consists of five items, mainly addressing intentional non-adherence behaviour (4 out of 5 items). The items are rated on a five-point Likert scale (from 1 (always) to 5 (never)), resulting in a summated score of 5-25 30. No standard cut-off point to define adherent versus nonadherent medication has been provided by the scale developers and it varies across studies 31. In this study the MARS-5 cut-off scores of ≥ 23 and ≥ 24 to identify adherent and non-adherent patients are both reported, as these are cut-off points that are more often used and because adherence distributions found with the MARS-5 are often highly skewed32-35.