Advance directives knowledge among primary healthcare professionals: a cross-sectional study in Portugal

Advance directives (ADs) are legal documents allowing individuals to express preferences for future medical care when unable to make decisions. In Portugal, ADs are regulated by Law No. 25/2012 and may be recorded in the National Registry of Advance Directives of Will. Primary healthcare professionals are often the first point of contact for citizens seeking information about ADs, yet evidence regarding their knowledge and preparedness in the Portuguese primary care context remains limited. This study aimed to assess ADs knowledge among primary healthcare professionals in Portugal and identify associated factors. A descriptive, observational, cross-sectional study was conducted among physicians and nurses working in Portuguese primary healthcare settings. Data were collected between October 2024 and February 2025 using an online questionnaire. The questionnaire included demographic characteristics, self-perceived knowledge assessment, and nine objective knowledge questions about ADs. Associations between objective knowledge scores and demographic, professional, academic, workplace-related, and previous training variables were assessed using non-parametric statistical tests. Of 600 submitted questionnaires, five were excluded due to incomplete responses, leaving 595 for analysis. Participants were predominantly female (76.6%) and were almost equally distributed between physicians (50.1%) and nurses (49.9%). Most reported no previous training in palliative care (68.6%) or bioethics (73.8%). The median objective knowledge score was 4 out of 9 correct answers (IQR 3–5). The highest proportions of correct answers were observed for the legal definition of ADs (65.0%) and validity requirements (50.1%), whereas the lowest proportions were found for documentation requirements (26.2%), professional obligations (31.8%), and clinical implementation (33.3%). Physicians scored higher than nurses [median 5 (IQR 4–6) vs. 4 (IQR 3–5), p < 0.001], and professionals with previous palliative care training scored higher than those without such training [median 5 (IQR 4–6) vs. 4 (IQR 3–5), p < 0.001]. Previous bioethics training was also associated with higher knowledge scores [median 5 (IQR 4–6) vs. 4 (IQR 3–5), p = 0.026]. Primary healthcare professionals in Portugal showed limited knowledge about ADs, despite high awareness of their own training needs. Targeted education in ADs, particularly within palliative care and bioethics training, may improve professionals’ preparedness to inform and support patients in future care planning.