Definition of the problem Patient-oriented care is a worthy goal. The recognition and avoidance of inadequate treatment, e.g., under-, or over-treatment, often results in doctors and nurses at the bedside being faced with making difficult decisions. The development of practical guidance that meets scientific criteria and is not solely based on consensus is highly desirable. Arguments The presented work attempts to formulate key standards to prevent over- and undertreatment and to confirm them theoretically. For this, a grading of autonomy is made by distinguishing between weak and strong autonomy, based on an interest-based ethics approach. Conclusions Interest-based ethics supports the view that orientation on strong autonomous decision making offers an optimal chance to promote well-being and may thereby help prevent a large proportion of under- and overtreatment.