[General practice of advance directives in the USA].

Advance directives are written documents which tell what a person wants or does not want if he/she in the future cannot make his/her wishes known about medical treatment. There are three major forms of advance directives in the US: living will, durable power of attorney, and medical directive. Even though advance directives have been used for over 25 years, probably no more than 20% of Americans have prepared a written directive. What are the reasons for this relatively small percentage? It has been argued that they run the opposing risks of either being too general or too specific and that they often use a vague and confusing terminology. Furthermore, the two most frequently cited barriers were the patient's expectation that the physician should take the initiative and the sense that such issues were only relevant for those who were older or in worse health. Progress in developing useful advance directives cannot stop with existing documents. A critical evaluation of advance directives and the development of new ideas will be necessary. Therein, the most important area for future efforts is empirical research.