Psychometric properties of the end-of-life care decision inventory (EOL-CDI): a mixed-methods study

End-of-life care decision-making has become important to support dignity and quality of life for patients who are facing death in Korea, along with the enactment of the Life-Sustaining Treatment Act in 2018. However, it seems that the concepts and policies related to the law are not yet familiar to health care providers or the general public. This unfamiliarity can hinder efficient end-of-life care discussions. Therefore, the purpose of this study was to propose a valid and reliable tool to explore the level of understanding of concepts and attributes related to end-of-life care decisions.

This is a mixed-methods study design. A relevant law and literature analysis, expert consultation, cognitive interviews of 10 adults, and cross-sectional survey for psychometric tests using data from 238 clinical nurses were performed to update a tool developed before the life-sustaining treatment Act was enacted in Korea.

29 items of the draft version were polished in terms of literacy, total length, and scoring method via cognitive interviews and finalized into 21 items through psychometric tests and expert consultations. The 21 items conformed to the Rasch unidimensional paramenters.

A tool to identify the level of understanding of concepts related to end-of-life care decisions was proposed through a rather rigorous process to ensure feasibility and validity/reliability. We recommend the proposed tool to apply to the adult population and nurses for evaluation and educational purposes.