[Is my patient able to provide informed consent? A practical guideline].

Patient autonomy is a fundamental issue. Sometimes it is unclear whether a patient is capable to consent to a treatment decision. The treating physician judges whether a patient is able to provide informed consent. This judgement is a medical and not a legal decision. Considerations as to whether a patient can provide informed consent should always be systematically and in detail included in the medical records and should be periodically re-evaluated. Even if a patient incapable to consent to a particular medical decision, efforts should be put into finding the optimal treatment (proportional, effective and least substantial). It can be useful to involve a psychiatrist as a second and independent judge of a patient's ability to provide informed consent. A psychiatrist can also judge whether a psychiatric or cognitive disorder influences the ability to consent.