Advance directives are an expression of a person’s autonomy regarding end-of-life care. An advance directive (AD) is a tool that enables the exercise of prospective autonomy. It serves as instructions for the care a person wishes to receive or refuses in the event they become incapable of expressing their preferences at the end of life.
The population’s knowledge about ADs is extremely low. Despite some cultural and clinical specificities of some study samples, the empirical data reveal a population with an important level of illiteracy about ADs. This fact has been maintained over time, as already noted in a systematic literature review conducted between 1994 and 2016 on the population’s knowledge about ADs [9], as well as other studies [10][11][12][13]. This is perhaps one of the most important data points to highlight because of its practical consequence, i.e., despite the existence of this instrument for the exercise of prospective autonomy, a citizen’s right, its residual knowledge contributes to the low rates in the implementation of ADs [9][14][15]. As mentioned before, these data have also been maintained over time, with the USA showing higher rates, and reporting that one-third of the population will have ADs [16][17]. Moreover, the rates are lower in Europe, and are between 0.66% and 19% [10][11][12][14][18][19]. There may be several reasons for this discrepancy, despite the cultural differences between populations, but it is necessary to note that in the USA, the discussion and legalisation of ADs began in the 1970s, while in most countries, especially European, discussion on this issue began only at the beginning of the 21st century [20][21]. Regardless of this time lag, which may justify some progress in the numbers in the USA, it seems to us that the knowledge deficit is a barrier to not starting the process of the elaboration of ADs [9][14].
The lack of knowledge about ADs is high, and as people were able to see from the studies in countries without a legal framework for ADs that the samples exhibited a lack of knowledge about ADs, with values exceeding 80%. Even so, in countries with a legal framework, the rates of lack of knowledge were 56.8% [22] and 47% [18], demonstrating that even with the implementation of a law, measures must be taken to increase the literacy of the population in this context. It seems that there is a need to involve political decision makers in the area of health and, simultaneously, involve health professionals so that projects can be developed in the community to provide citizens with more information and training to prepare ADs [9][23][24].
Even so, the attitudes and perceptions about ADs are very favourable, which indicates that, despite the populations’ low levels of knowledge in this area, when they are informed about what an AD entails, they provide a very positive assessment and display a growing interest in the subject. In some studies, participants have the following perceptions about the added value of ADs: respect for the person’s autonomy, avoiding therapeutic futility, ensuring comfort at the end of life, and relieving the family and physicians from ethical decision making in end-of-life care. These are in the same line of evidence pointed out by other studies [9][17][24].
An important fact about communication in end-of-life care planning and the role of health professionals should be highlighted. Other studies confirm the importance of individuals discussing the care they receive or decline at the end of life. For the participants in the research studies, this conversation would be important and more effective for elaborating ADs if they had the support of a healthcare professional [25][26][27][28][29][30]. It seems evident to us that a citizen, when faced with doubts which are admittedly technical, should want to obtain advice. Incidentally, this idea is already in practice in the USA under the Federal Patient Self-Determination Act of 1990, and health institutions are obliged to inform citizens of their right to prepare their AD and to provide advice to this effect [31][32].