The differential diagnosis of nonadherence
| Type of nonadherence | Characteristics |
| Unwitting | Misunderstand dosing regimen, fail to understand rationale for treatment |
| Erratic (or chaotic) | Difficulty following treatment because of its complexity or because of chaos of patients' lives |
| Deliberate (or intelligent) | Deliberately decide that perceived concerns of medication outweigh its perceived need |
Adapted from [4] and [16].