Factors related to advance directives completion among cancer patients: a systematic review.

INTRODUCTION: Advance directives (ADs) has recently been considered as an important component of palliative care for patients with advanced cancer and is a legally binding directive regarding a person's future medical care. It is used when a person is unable to participate in the decision-making process about their own care. Therefore, the present systematic review investigated the factors related to ADs from the perspective of cancer patients.

METHODS: A systematic review study was searched in four scientific databases: PubMed, Medline, Scopus, Web of Science, and ProQuest using with related keywords and without date restrictions. The quality of the studies was assessed using the Hawker criterion. The research papers were analyzed as directed content analysis based on the theory of planned behavior.

RESULTS: Out of 5900 research papers found, 22 were included in the study. The perspectives of 9061 cancer patients were investigated, of whom 4347 were men and 4714 were women. The mean ± SD of the patients' age was 62.04 ± 6.44. According to TPB, factors affecting ADs were categorized into four categories, including attitude, subjective norm, perceived behavioral control, and external factors affecting the model. The attitude category includes two subcategories: "Lack of knowledge of the ADs concept" and "Previous experience of the disease", the subjective norm category includes three subcategories: "Social support and interaction with family", "Respecting the patient's wishes" and "EOL care choices". Also, the category of perceived control behavior was categorized into two sub-categories: "Decision-making" and "Access to the healthcare system", as well as external factors affecting the model, including "socio-demographic characteristics".

CONCLUSION: The studies indicate that attention to EOL care and the wishes of patients regarding receiving medical care and preservation of human dignity, the importance of facilitating open communication between patients and their families, and different perspectives on providing information, communicating bad news and making decisions require culturally sensitive approaches. Finally, the training of cancer care professionals in the palliative care practice, promoting the participation of health care professionals in ADs activities and creating an AD-positive attitude should be strongly encouraged.