[Indication: scientific and ethical basis of medical practice].

The medical indication provides a rational foundation for treatment decisions. An indication can be defined as the reasonable professional judgement that a medical procedure is suitable and useful to reach a specific therapeutic goal with a certain probability. An indication includes empirical, causal and purposive considerations and justifications, and a scrutiny of the individual case. This ensures that medical aspects of the patient, therapeutic goals and evidence-based knowledge are integrated and represented in the indication. An indication justifies a treatment proposal to the patient, which may only be carried out after a procedure of informed consent. Indications can be considered as the ethical basis of treatment decisions and as the heart of professionalism: indications should be used as a professional tool to protect against irrational therapeutic expectations, while ensuring the patient's right for reasonable treatment. In health care that is increasingly shaped by economic constraints, conscientious indications ensure the professional and ethical basis of medical treatment decisions.