Introduction

Background

According to Administrative Statistics by Life Cycle in 2023, as of November 1, 2023, the number of middle-aged people (ages 40∼64) in Korea is 20,178,000, accounting for 40.5% of the total population. Regarding the age distribution, the 40-49 age group accounts for 15.3% of the total population, the 50-59 age group, 16.8%, and the 60-64 age group, 8.3%, and in the middle-aged population, the 60-64 age group (4,147,000 people) takes up the largest proportion after the 50-54 age group (4,343,000 people) [1]. This data indicates that a large number of middle-aged people in Korea are close to old age, the stage of life for those aged 65 or older.

Middle age, called the afternoon of life, serves as a bridge between the first and second half of life, and thus plays a pivotal role in the transition to old age, called the evening of life, in mental, physical, and socioeconomic aspects, and it typically refers to the period of life from age 40 to age 64 [2]. In particular, middle age is the period of life when people seek to balance growth and decline at the crossroads of youth and old age, and reach their peak for both income and social status, which leads to the increase of their self-confidence [3]. As a result, during middle age, improved self-determination, strengthened leadership within the family, and increased social contributions may have a positive impact on children, elderly parents, and the community, and this positive influence can be increased as self-esteem becomes higher [4,5].

Self-esteem is individuals’ subjective evaluation of their inherent worth or value, and encompasses self-acceptance and self-respect, so it involves placing importance on life values, and is a core psychological resource closely related to self-determination [3,5,6]. Middle-aged people with high self-esteem are likely to focus on the quality of well-being and the value of well-dying, and take a self-initiated attitude in health-related decision-making situations [3,4,6]. Therefore, since self-esteem in middle-aged people reflects an individual’s values about life and altruistic self-determination, it is significant as a major variable that can explain attitudes toward advance directives because advance directives are related to seeking solutions to sensitive social issues such as organ donation, euthanasia, and advance care planning (ACP) as well as sharing common social values through self-determination [5,7,8]. In particular, it has been reported that while positive self-esteem decreases in old age, negative self-esteem decreases in middle age [9]. Therefore, positive self-esteem in middle-aged adults, who are nearing old age, may have a significant impact on the society regarding self-determination regarding one’s body after death, quality of life and dignity at the end of life [6], and preparation for a dignified death [7].

Organ donation is a legitimate process for transplanting organs from a living or deceased donor to another person, and it has been reported that one person’s organ donation can save 8 people and improve quality of life in 50 people [10]. In particular, since organ donation is a decision regarding the use of one’s body after death in consideration of what happens after death, it can lead to a self-initiated, proactive attitude toward self-determination regarding whether to receive end-of-life treatment, and thus organ donation can have a positive influence on the formation of attitudes toward advance directives as preparation for one’s end of life [7,10].

In recent years, with technological advances in medicine, both life expectancy and the number of people with chronic diseases have increased, and amid the increase of patients in need of organ transplants, the shortage of donors is getting worse. According to the ‘2024 Annual Report’ of the Korea Organ Donation Agency, the sole organ and tissue procurement organization in Korea designated by the Ministry of Health and Welfare, the number of registered organ donors decreased from 139,090 people in 2023 to 117,206 people in 2024, and the number of brain-dead organ donors decreased from 483 in 2023 to 397 in 2024 [11]. Regarding the number of brain-dead organ donors by age group, the 50-59 age group was reported to account for the highest proportion with 105 people. Thus, proper awareness and attitudes toward organ donation among middle-aged people are very important, but there is a lack of research to support this point.

Euthanasia refers to a medical intervention that intentionally ends a person’s life within a medical setting to relieve a patient’s pain and suffering, and includes the withdrawal of life-sustaining treatment and of life support, and the Netherlands and Switzerland are representative countries where this practice is legal [12,13]. Korea has established the timing and subjects for withdrawal of life-sustaining treatment through the ‘Act on Hospice and Palliative Care and Decisions on Life-Sustaining Treatment for Patients at the End of Life (Act on Decisions on Life-Sustaining Treatment)’ [14], but withdrawal of life-sustaining treatment is emerging as a social issue due to conflicts of interest involving various issues such as dignity of life and moral, ethical, cultural, and religious issues [13]. Recently, as social perceptions regarding euthanasia have changed and the importance of patients’ self-determination has been raised as an issue, there have appeared middle-aged people with the opinion that they want to have a dignified death and die a death that reflects their own decisions [6]. In view of this current situation, there is a need to carefully reexamine attitudes toward euthanasia among middle-aged people. It has been pointed out that middle-aged people have psychological and economic burdens regarding planning for retirement and old age and preparing for death, and that a person should prepare a dignified death from young age [12], which can lead to positive attitudes toward euthanasia [15]. Nevertheless, there has been limited research on this issue. Since a positive attitude toward euthanasia means accepting the value of a dignified death and active euthanasia, it can be a major factor in explaining attitudes toward advance directives, which involves the choice of passive withdrawal of treatment through the withdrawal of meaningless life-sustaining treatment [6,12,13,15].

Advance directives (hereinafter AD) are documents (including electronic documents) that states the decisions and wishes of a person aged 19 or older regarding the withdrawal of life-sustaining treatment and regarding hospice and palliative care, and include a living will and proxy designation [14]. It is recommended that an individual should complete an AD while he or she is healthy and young, because confirming one’s wishes regarding one’s medical treatment in advance can facilitate medical staff’s early determination of treatment plans and reduce the burden of decision-making on the family [16-18]. However, young people tend to view death as a future event and not perceive it as a realistic problem, while elderly people are highly likely to avoid mentioning death or have limitations in making an advance decision or completing an AD due to physical and cognitive limitations [19]. On the other hand, married middle-aged adults, who have the experience of caring for the spouse, children, and parents and are primary decision-makers within the family, play an important role in solving family-level health and bioethical issues, so they are likely to recognize both the necessity and reality of preparing for AD [3,5-7,20], but there is a lack of research on preparing for AD among married middle-aged adults.

Individuals’ lifestyles and quality of life in old age are influenced by their life in middle age [3]. If adequate preparations for organ donation, euthanasia, and AD are made during middle age, it would lead to a dignified life in old age and altruistic completion of the life journey, and high self-esteem can serve as a psychological resource in middle age [3,21]. Attitudes toward organ donation and euthanasia formed on this psychological basis may influence self-determination regarding one’s body after death and value judgments regarding end-of-life treatment choices, and as a result, these attitudes can be embodied as attitudes toward AD [10,12,13,17].

However, in most of the previous studies that investigated knowledge and attitudes toward AD, knowledge and attitudes toward a good death and organ donation, or the impact of self-esteem on AD, the target groups were nursing students [8], healthcare providers [15], the elderly [22], the general public [23], patients in the palliative care unit of a hospital [24], and different ethnic groups [7]. On the other hand, there is a severe lack of research to investigate self-esteem and attitudes toward organ donation, euthanasia, and AD among married middle-aged adults. In particular, considering that AD has been shown to have a positive correlation with organ donation and euthanasia [16,23], and that groups with high self-esteem has been reported to have positive attitudes toward organ donation and AD [7], there is a need for research to analyze and identify the factors influencing attitudes toward AD and develop interventions to mitigate or enhance the influencing variables in a positive direction. In addition, married middle-aged adults are highly likely to experience their parents’ aging and death firsthand, and repeatedly have an opportunity to make a bioethical decision within their relationships with their spouse and children. In contrast, unmarried middle-aged adults have fewer opportunities for decision making and caregiving roles within the family due to the absence of the spouse and children, so their attitudes toward organ donation, euthanasia, and AD are highly likely to be be biased toward a self-oriented perspective [20,25-27].

Against the above backdrop, this study aimed to investigate the levels of self-esteem and attitudes toward organ donation, euthanasia, and AD among married middle-aged adults and identify factors affecting attitudes toward AD in order to provide foundational data for the development of a multidisciplinary intervention program based on the influencing factors for attitudes toward AD derived from the analysis.

Aims

This study aimed to investigate the levels of self-esteem and attitudes toward organ donation, euthanasia, and AD among married middle-aged men and women residing in six regions including Seoul, and to identify the variables influencing attitudes toward AD and how they affect attitudes toward AD among middle-aged adults.

Methods

Study design

This study is a descriptive survey research to investigate the impacts of self-esteem, attitudes toward organ donation (ATOD), and attitudes toward euthanasia (ATE) on attitudes toward AD (ATAD) among married middle-aged adults.

Participants

The participants of this study were married middle-aged men and women residing in six regions including Seoul. Only those who understood the purpose of the study and voluntarily agreed to participate were included in the study. Unmarried middle-aged adults were excluded from the study because their family structure, social support networks, and contexts of end-of-life decision-making may be different from those of married middle-aged adults [25,27]. In addition, noting that AD is a system that is mediated by family-centered decision-making beyond the declaration of an individual’s right [20,26], married middle-aged adults were set as the key target group of the study because middle age is the period when family roles and responsibilities are increased and take on greater importance in individuals’ life [2-4].

The sample size for this study was calculated using the G*POWER 3.1 Program [28] with a significance level (α) of .05, a power (1-β) of .80, an effect size of .15, and 17 predictors (13 general characteristics and 4 independent variables), based on the study by Kang [29]. The minimum sample size was calculated as 146 people, but considering a dropout rate of 20% [29], 183 people (146/(1-0.2)=183 people) were surveyed. Of the 183 people, 154 people were included in the final analysis for this study, excluding 29 questionnaires (dropout rate: 15.8%) due to inappropriately responses (omission, confusing or incomplete responses, double marking, or withdrawal).

Measures

Awareness is simply a state of having knowledge and is mainly limited to the cognitive domain, but the concept of ‘attitude’ includes all the three elements of cognition, affect, and behavior [30]. Therefore, to conduct an in-depth analysis of the actual behavioral changes and psychological mechanisms regarding the research topic of this study, the concept of ‘attitude,’ which is a more comprehensive concept than awareness, and involves motivation for action and behavioral intention, was used as the key unit of analysis.

1. Self-esteem (SE)

Self-esteem was assessed using the Korean version of Rosenberg’s Self-Esteem Scale (SES) presented by Lee et al. [31] with the permission of the authors. The Korean version used has been validated through validity and reliability analysis by Lee et al. [31]. This tool is a unidimensional scale without subdomains, and consists of a total of 10 items, including 5 positive items and 5 negative items. Each item is rated on a 5-point scale, and a higher score indicates a higher level of self-esteem. Regarding the reliability of the scale, the value of Cronbach’s α was reported to range from .75 to .87 (.75 for elementary school students, .80 for middle school students, 0.80 for high school students, and 0.87 for college students) in the study by Lee et al. [31], and it was calculated as .94 in this study.

2. Attitudes toward organ donation (ATOD)

ATOD was measured using the human tissue donation and transplantation attitude scale presented by Kwon [32] with the permission of the author. The used scale was the version modified and supplemented by Kwon [32] with the approval from the developer of the original scale. This tool is a unidimensional scale without subdomains, and consists a total of 18 items: 13 items on positive attitudes and 5 items on negative attitudes. Each item is rated on a 5-point scale, and a higher score indicates a more positive attitude toward organ donation. Regarding the reliability of the scale, the value of Cronbach’s α was .76 in the study by Kwon [32] and .93 in the present study.

3. Attitudes toward euthanasia (ATE)

ATE was measured using the tool developed by Kim [33] with the permission of the author. This tool consists of a total of 19 items across 4 subdomains: 9 items on quality of life 9, 6 items on respect for life, 2 items on medical ethics, and 2 items on patient rights. Higher scores indicate more positive ATE. As for the reliability of the scale, the value of Cronbach’s α was .88 in the study by Kim [33] and .95 in the present study.

4. Attitudes toward Advance Directives (ATAD)

ATAD was assessed using the Advance Directive Attitude Survey (ADAS) tool with the permission of the authors [34]. The used tool was the version revised and supplemented by Lee and Park [34] after obtaining approval from the original author. This tool consisted of a total of 16 items across 4 subdomains: 4 items on opportunity for treatment choices, 8 items on impact of AD on the family, 3 items on effects of AD on treatment, and 1 item on illness perception. Each item is rated on a 4-point scale without a midpoint. However, it has been pointed that the midpoint of the Likert scale serves as a safe haven that allows respondents to overcome cognitive demands associated with the survey items, and express a neutral position, and that omitting the midpoint can decrease the validity of survey items [35]. Therefore, in order to allow respondents to express a neutral position, the scale was modified to a 5-point scale based on the consensus of the expert group of this study, which consisted of a head nurse from a hospice ward in a general hospital, a nursing director of a long-term care hospital for the elderly, and a nursing professor in the field of geriatric and adult nursing. Then, content validity was verified based on the study by Polit et al. [36], and the average content validity index (CVI) was calculated to be .90. The total score ranges from 16 to 80 points, and higher scores indicate more positive ATAD. Regarding the reliability of this scale, the value of Cronbach’s α was .79 in the study by Lee and Park [34] and .94 in this study.

Data collection

The data collection was conducted from July to September 2025. To recruit community-dwelling middle-aged men and women from various regions, 8 college students residing in different regions who voluntarily expressed willingness to participate were selected as research assistants. To secure inter-rater reliability, the purpose of the study, the content of the survey, and the methods of completing and collecting questionnaires were explained before starting the study. After checking for redundancy and ambiguity in the survey items, a simulation process was carried out by performing a mock survey in front of the researcher. Then, the actual survey was conducted after recruiting participants and obtaining written informed consent from them. To recruit participants, research assistants visited places such as local cafes, parent gatherings, and gyms in the regions where they were living, explained the purpose and methods of the study to potential participants, and obtained written consent from the participants who voluntarily expressed their willingness to participate. Although the time taken to respond to the survey varied among the respondents, it took about 10 to 20 minutes to complete the questionnaire, and after the survey was completed, a small gift was given to all the participants as a token of appreciation.

Ethical considerations

This study was conducted after receiving approval (IRB No. 1044297-HR-202505-001-02) through a review by the Institutional Review Board of Jungwon University, which is the affiliated institution of the researcher. To ensure the reliability of the study and protect the rights of the participants, before conducting the survey, the participants were informed that their anonymity would be guaranteed and that they had the right to withdraw from participation at any time without any disadvantages. In addition, it was explained to the participants that all collected data would be used solely for the purposes of this study and would not be used for any other purpose. It was also explained that the collected questionnaires and analysis data would be safely stored in a lockable filing cabinet in the researcher’s office for three years, and would be completely disposed of by shredding after the completion of the study and publication of the paper.

Data analysis

The collected data was analyzed using SPSS version 23.0. The general characteristics of the participants were analyzed by calculating frequencies, percentages, means, and standard deviations. The levels of self-esteem, ATOD, ATE, and ATAD were also analyzed using means and standard deviations. The differences in the levels of independent variables, such as self-esteem, ATOD, ATE, and ATAD, according to general characteristics were analyzed using the independent t-test and one-way ANOVA. Post hoc tests for differences between groups were performed using the Scheffé post hoc test. The correlations between self-esteem, ATOD, ATE, and ATAD among the participants were analyzed using Pearson’s correlation coefficient. To examine the effects of control and independent variables on ATAD among middle-aged adults, the dependent variable, hierarchical regression analysis was performed by entering variables in a stepwise manner, and the increase in the explanatory power (change in R²) of the variables was evaluated stepwise. Hierarchical regression analysis has the advantage of strengthening the logical basis and reliability of the interpretations of research results in the following respects. First, this analysis method enables the identification of the pure impacts of major variables entered in subsequent steps on the dependent variable by entering control variables such as gender and age in Step 1. In addition, hierarchical regression analysis shows changes in explanatory power and statistical significance through stepwise analysis results.

Results

Differences in the levels of SE, ATOD, ATE, and ATAD according to general characteristics among middle-aged adults

Of a total of 154 participants, 103 people were female (66.9%). In terms of age, the 50–59 age group took up the largest proportion (76 people, 49.4%). In education level, people with secondary education (78 people, 50.6%) took up a slightly larger proportion than those with higher education (76 people, 49.4%). As to the presence of religion and a job, 86 people (55.8%) had religion and 126 people (81.8%) had a job. In terms of finance, 114 people (74.0%) reported their finance level as ‘average.’ In the case of ethical values, 93 people (60.4%) showed a ‘low’ level of ethical values. Regarding the experience of receiving bioethics education, 95 people (61.7%) answered that they did not receive it. As to the awareness of advance directives (AD) and life-sustaining treatment (LST), when asked whether they knew about AD and LST, 106 people (68.8%) and 125 people (81.2%) answered ‘Yes’, respectively. Regarding thinking about a good death, 79 people (51.3%) answered that they had never thought about it. As to thinking about organ donation, 77 people (50.0%) responded that they had often thought about it. In the case of thinking about euthanasia, 67 people (43.5%) reported that they had never thought about it.

In this study, there were significant differences in the level of SE according to the finance level (F=10.42, p<.001), ethical values (t=6.24, p<.001), experience of receiving bioethics education (t=3.60, p<.001), awareness of AD (t=2.23, p=.027), and frequency of thinking about a good death (F=3.82, p=.024). In other words, a higher level of SE was associated with a high finance level, a high level of ethical values, experience of receiving bioethics education, awareness of AD, and frequently thinking about a good death. Regarding ATOD, there were differences in ATOD according to age (F=10.67, p<.001), religion (t=2.15, p=0.33), bioethics education (t=3.52, p=.001), awareness of AD (t=3.80, p<.001), awareness of LST (t=2.18, p=.031), frequency of thinking about organ donation (F=37.35, p<.001), and frequency of thinking about euthanasia (F=12.40, p<.001). In other words, positive ATOD was associated with being in the 40-49 age group, presence of religion, experience of receiving bioethics education, awareness of AD, awareness of LST, thinking about organ donation, and thinking thought about euthanasia. With respect to ATE, the level of this variable varied according to awareness of AD (t=2.25, p=.026), frequency of thinking about organ donation (F=6.22 p=.003), and frequency of thinking about euthanasia (F=59.81, p<.001). Specifically, positive ATE was observed in the group with awareness of AD and the groups that often thought about organ donation and euthanasia. As for ATAD, there were differences in ATAD according to age (F=3.93, p=.022), religion (t=2.40, p=.018), ethical values (t=1.98, p=.049), bioethics education (t=2.36, p=.020), awareness of AD (t=5.54, p<.001), awareness of LST (t=2.06, p=.041), frequency of thinking about organ donation (F=12.38, p<.001), and frequency of thinking about euthanasia (F=14.18, p<.001). In other words, among the participants, positive ATAD was associated with being in the 60-64 age group, presence of religion, a high level of ethical values, experience of receiving bioethics education, awareness of AD, awareness of LST, and frequently thinking about organ donation, and often thinking about euthanasia (Table 1).

Levels of SE, ATOD, ATE, and ATAD among middle-aged adults

The average score for SE was 3.76 (±0.72) points, and the average scores for ATOD, euthanasia, and AD were 3.80 (±0.62) points, 3.90 (±0.79) points, and 3.93 (±0.69) points, respectively. Among the four subdomains of ATE, ‘quality of life’ had the highest score at 4.00 (±0.75) points, and ‘respect for life had the lowest score at 3.75 (±0.80) points. Among the four subdomains of ATAD, ‘illness perception’ had the highest score at 4.05 (±0.80) points, and ‘effects of AD on treatment’ had the lowest score at 3.88 (±0.70) points (Table 2).

Correlations between SE, ATOD, ATE, and ATAD

The results of correlation analysis between SE, ATOD, ATE, and ATAD revealed that SE had a statistically significant positive correlation with all the attitude variables of ATOD (r=.386, p<.001), ATE (r=.170, p=.035), and ATAD (r=.462, p<.001). Also, ATE had a significant positive correlation with ATOD (r=.402, p<.001). Additionally, ATAD had a significant positive correlation with ATOD (r=.677, p<.001) and ATE (r=.384, p<.001). In other words, a higher level of SE was associated with more positive ATOD, ATE, and ATAD. In addition, more positive ATE was associated with more positive ATOD. Further, more positive ATAD were linked to more positive ATOD and ATE (Table 3).

Factors affecting ATAD among middle-aged adults

Hierarchical regression analysis was performed to identify the factors influencing attitudes toward AD (ATAD) among the participants. First, to adjust for the effects of control variables that may influence the dependent variable, basic explanatory power was secured by entering variables that showed statistically significant differences in the univariate analysis in Step 1. In other words, in Step 1, we entered age, religion, ethical values, experience with bioethics education, awareness of AD and life-sustaining treatment, and frequency of thinking about organ donation and euthanasia (reference group: the 60-69 age group, presence of religion, strong (high) ethical values, presence of experience of receiving bioethics education, awareness of AD, awareness of life-sustaining treatment, often thinking about organ donation, and often thinking about euthanasia). Then, to examine whether major independent variables provided additional explanatory power, SE, ATOD, and ATE, which showed a significant positive correlation with ATAD, were entered in a stepwise manner. To examine the goodness of fit of the regression model, the independence between residuals was checked using the Durbin-Watson test, and the Durbin-Watson statistic was calculated as 2.11. This value is not close to the values indicating the presence of autocorrelation, which is 0 or 4, but it is close to 2, which represents a normal distribution. Since the Durbin-Watson statistic indicated that there was no autocorrelation between the residuals, the assumption of independence of the regression model was met. To detect multicollinearity, tolerance and Variance Inflation Factor (VIF) values were calculated. As a result, the tolerance value ranged from 0.35 to 0.86, which was higher than the threshold of 0.1, and the VIF value ranged from 1.15 to 2.95, which was lower than the threshold of 10, so it was confirmed that there was no problem with multicollinearity.

The results of the hierarchical multiple regression analysis showed that Model I was statistically significant with F=6.92, p<.001, and explained 34% of the variance in ATAD in middle-aged adults. The strongest influencing variable was lack of awareness of AD (β=-.39, p<.001), followed by ‘sometimes’ thinking about organ donation (β=-.33, p<.001), absence of religion (β=-.18, p=.015), and ‘never’ thinking about organ donation (β=-.18, p=.027). In other words, awareness of AD, a high frequency of thinking about organ donation, and presence of religion had a positive influence on ATAD. Model II was statistically significant with F=11.01, p<.001, and explained 48% of the variance in ATAD in middle-aged adults, so there was a 14% increase in explanatory power compared to Model I. The strongest influencing variable was SE (β=.43, p<.001), followed by lack of awareness of AD (β=-.39, p<.001), ‘sometimes’ thinking about organ donation (β=-.28, p<.001), lack of religion (β=-.18, p=.004), and a ‘low’ level of ethical values (β=.15, p=.031). In other words, high SE, awareness of AD, a high frequency of thinking about organ donation, presence of religion, and a high level of ethical values had a positive effect on ATAD. Model III was statistically significant with F=27.87 and p<.001, and explained 72% of the variance in ATAD in middle-aged adults, so it showed a 24% increase in explanatory power compared to Model II. The strongest influencing variable was ATOD (β=.22, p=.003), followed by being in the 40-49 age group (β=.20, p=.005), lack of awareness of AD (β=-.18, p=.002), SE (β=.14, p=.013), and lack of religion (β=-.11, p=.017). In other words, a high level of ATOD, being in the 40-49 age group, awareness of AD, a high level of SE, and presence of religion positively affected ATAD. Model IV was statistically significant (F=26.23, p<.001, and explained 74% of the variance in ATAD, so there was a 2.0% increase in explanatory power compared to Model III. The strongest influencing variable was ATOD (β=.22, p=.002), followed by being in the 40-49 age group (β=.19, p=.006), lack of awareness of AD (β=-.18, p=.002), SE (β=.14, p=.016), ‘sometimes’ thinking about organ donation (β=-.13, p=.035), and lack of religion (β=-.10, p=.025). In other words, a high level of ATOD, the 40-49 age group, awareness of AD, a high level of SE, a high frequency of thinking about organ donation, and presence of religion positively influenced ATAD (Table 4).

Discussion

The results of this study showed that with respect to the relationship between SE and general characteristics among middle-aged adults, a higher level of SE was associated with a high finance level, a high level of ethical values, experience of receiving bioethics education, awareness of AD, and frequently thinking about a good death. These results are similar to the findings of the study by Yoo [9], which analyzed the trajectory of changes in SE among Korean adults over 10 years (2006–2015), and the study by Nakakita et al. [37], which analyzed the factors affecting SE among Japanese adults over 9 years (2014–2022). These prior studies reported that a higher level of SE was associated with a higher income level and better socioeconomic conditions. Meanwhile, Kwon and Kim [38] investigated perception about a good death and knowledge and attitudes regarding AD among 154 middle-aged women, and found that a high level of SE was positively correlated with perception about a good death, organ donation, and ATAD. In addition, Ha [8] reported that the group with high ethical values has higher SE than the group with low ethical values, and that ethical values are an important factor in the formation of bioethics awareness. Therefore, SE among middle-aged adults is closely related to perceived meaning of life, ethical values, and attitudes toward death [6,15], and bioethics education is a variable highly correlated with ethical values, AD, and a good death [8,38]. Taken together, these findings of previous studies suggest that a multidisciplinary intervention strategy is needed to enhance SE. In particular, web-based educational programs utilizing mobile or internet platforms and network technologies can be considered as an intervention method that can contribute to the enhancement of SE, considering that such programs allow people to participate in education programs online without accessibility constraints or spatial and temporal constraints, and facilitate the participation of multidisciplinary experts, thus making it possible to reflect the characteristics of middle age, which is the life stage when people actively engage in socioeconomic activities [39]. In addition, such web-based programs have the advantage of allowing couples and families to participate together, so they can be utilized as an intervention strategy tailored to the characteristics of married middle-aged adults formed through a relational context.

With respect to ATOD according to general characteristics, the level of ATOD was higher among the 50-64 age group than the 40-49 age group, and it was also higher in the group with religion, the group that received bioethics education, the group with awareness of AD and LST, and the groups that often thought about organ donation and euthanasia. A relatively lower level of ATOD in the 40-49 age group may be attributed to the fact that people in their 40s are younger compared to those in their 50s or older, and this finding is similar to the results of the study by Puente et al. [19], which found that younger people are more likely to avoid organ donation and thoughts of death. However, in contrast with the present study’s findings regarding age and organ donation, the study of 420 people aged 65 and older in Spain by Febrero et al. [22] reported that the results of a survey on ATOD showed that the number of people who expressed no intention to donate organs increased with age. Febrero et al. [22] attributed their findings to a lack of understanding and promotion regarding organ donation. Therefore, a strategy to increase public awareness of organ donation is required, and it is believed that a stepwise promotional program using leaflets, pamphlets, and brochures is effective in terms of low costs and high efficiency. Religion is closely related to ATOD. Bennett and Savani [7] interviewed 336 people aged 40 or older, and found that more religious people showed more positive ATOD. Also, Khalifa et al. [10] reported that 87.7% of 406 local residents responded that organ donation is a humanitarian and religious duty. These prior studies support the present study’s findings about the association between religion and ATOD. However, Krupic [40] interviewed 36 people aged 30 to 70 and found that while most religions are favorable toward organ donation, there are different views within religions. In addition, Irving et al. [41] stated that there are very complex conflicts of interest involving religious and cultural issues regarding organ donation, and that the main causes are a lack of understanding and distrust regarding organ donation. These findings suggest that it is required to establish a regular communication channel between religious organizations and government agencies related to organ donation. Meanwhile, Yoon [42] reported that bioethics awareness and religion are the foundation of awareness of organ donation. Also, Hong and Lee [16] and Kwon and Kim [38] reported that awareness of bioethics and religion can have a positive influence on knowledge and attitudes toward a good death, AD, and LST. In addition, Vanderveken et al. [15] reported that systematized bioethics education can provide an opportunity to provide a proper understanding of euthanasia. Thus, it is also important to develop educational programs linked to these variables based on the results of this study. However, considering that medical systems and socio-cultural situations regarding organ donation vary from country to country, and there are various religions, there is a need to consider intervention strategies that reflect these factors. Considering the domestic reality where decisions on organ donation are not made solely by individuals’ choices but are closely related to the consent of the family, ‘Re-born Life Sharing Cafe’ and ‘Organ Donation Promotion Workshops’ [11], which can promote family-level communication, can be utilized as strategies for married middle-aged adults. In particular, it is believed that such family-participatory programs can be employed as a practical intervention strategy that community nurses can lead, and they have practical nursing implications in that these programs can help individuals’ intention to donate organs lead to actual decisions based on their family’s understanding and support by reflecting the life experiences and the characteristic of family-centered decision-making of married middle-aged adults.

Regarding the level of ATE according to general characteristics, positive ATE were linked to awareness of AD, a high frequency of thinking about organ donation, and a high frequency of thinking about euthanasia. These results are in line with the results of the study by Vanderveken et al. [15], the study by Inglehart et al. [43], and the study by Jung and Choi [6]. These prior studies reported that one of the 11 conditions for a good death is to die a comfortable death without pain and with dignity, and that to have such a good death, it is important to have a proper understanding of AD, and have a sufficient conversation with a physician about euthanasia. In particular, Jansen and Gardiner [44] reported that the success rate of kidney transplantation from donors following euthanasia in the Netherlands over the past 10 years has been excellent. This report has provided a foundation for dispelling misconceptions about organ donation following euthanasia, but linking euthanasia with organ donation is legally and ethically controversial, and further research is needed regarding this issue.

Regarding the level of ATAD according to general characteristics, the level of ATAD was found to be higher in the ≥60 age group, the group with religion, the group with a high level of ethical values, the group with experience of receiving bioethics education, the group with awareness of AD, the group with awareness of LST, the group with a high frequency of thinking about organ donation, and the group with a high frequency of thinking about euthanasia. These results are similar to those of the study of 131 people from the general public by Ryu [23], which found that the level of ATAD was higher in the ≥ 65 age group. The findings of this study are also consistent with the study of 142 middle-aged patients by Suh and Kim [18], which reported that the group with religion showed a higher level of ATAD. However, differences in the age distribution of the participants put limitations on comparative analysis between the two prior studies and this study. However, some previous studies reported conflicting results. For example, the study by Kwon and Kim [38] reported that the level of ATAD was higher in the 50-59 age group than in the 60-69 age group. Moreover, Yoon et al. [24] and Lee and Park [34] reported that there was no differences in ATAD according to religion. However, the findings of this study are supported by a number of previous studies. In other words, it has been reported that the group with religion has strong beliefs in ethical values [18], shows positive attitudes toward a good death, AD, and withdrawal of life-sustaining treatment [15], and shows great interest in organ donation and euthanasia [43]. Therefore, customized educational intervention strategies are needed to reinforce these variables in a positive direction. Considering that the participants of this study were married adults, community-based programs that take into account ethical values and religious backgrounds, such as ‘family-unit small group discussions,’ ‘religious-based community customized programs,’ and ‘creating a list of final wishes with the family,’ can be employed as strategies to share family experiences and religious backgrounds, enhance ATAD, and link them to the motivation for completion of AD.

In this study, average scores for SE, ATOD, ATE, and ATAD among middle-aged men and women were 3.7 points or higher (out of 5 points). In particular, the scores for ATAD and ATE were highest at 3.93 and 3.90 points, respectively. The score for ATAD in this study is higher than the scores reported in several previous studies, including 3.59 points (out of 5) in a study of 211 middle-aged people by Yoo and Lee [45], 3.85 points (out of 5) in a study of the general population by Ryu [23], and 3.78 points in a study of college students by Ha [8]. For ATE among middle-aged people, although there are limitations to comparative analysis due to a lack of relevant prior research, the score for ATE in this study are similar to the results of the study by Ha [8], which reported that the score for perception of euthanasia among college students was 3.94 points. Compared to the results of previous studies, a relatively higher score for ATAD in this study is thought to be due to the general characteristics of the participants of this study, such as most of the participants’ high education level, relatively high level of knowledge of AD, and positive views on a good death, organ donation, and euthanasia, but further follow-up research is required.

The results of this study showed that there are strong positive correlations between SE, ATOD, ATE, and ATAD. In this connection, the study by Suh and Kim [18] found that there were correlations between SE, a good death, and AD. In addition, Vanderveken et al. [15] reported that high SE showed a positive correlation with positive ATE and ATAD. Also, the study by Hong and Lee [16] reported that individuals tend to consider organ donation when completing AD. Further, the study by Bennett and Savani [7] showed that there was a positive correlation between SE and organ donation. These findings of previous studies support the correlations between the major variables in this study. Therefore, based on previous studies [7,15,16,18], there is a need to develop programs tailored to married adults for strengthening self-determination through the enhancement of SE, such as ‘self-esteem-centered family-based integrated end-of-life education.’ Such educational programs for married adults should allow participants to share the programs and participate together with their family. It is thought that these intervention strategies will help to bring about comprehensive changes in ATOD and AD by employing individuals’ internal assets (self-esteem), and serve as a foundation for increasing the motivation for completion of AD, which can lead to actually signing an AD through family communication.

The results of this study showed that ATOD, being in the 40-49 age group, awareness of AD, SE, frequently thinking about organ donation, and presence of religion were influencing variables for ATAD. In particular, ATOD were found to be the strongest influencing variable affecting ATAD. Consistent with this study, the study by Wagner et al. [46] reported that most registered organ donors were found to have completed AD, and the study by Robinson and Paes [47] reported that an individual’s thoughts on organ donation can have a positive influence on completion of AD and should therefore be reflected in advance care planning (ACP). Completion of AD is an individual’s advance decision for a dignified death that alleviates the burden of medical costs on the family and the nation [38], and organ donation decisions made through AD can contribute to saving and extending precious lives and the realization of social values [10]. However, misinformation about organ donation and AD, a lack of publicity about them, and cultural and religious beliefs have been pointed out as obstacles [21,48,49], so it is considered that a pan-societal, multidisciplinary approach is needed to overcome these obstacles to organ donation and completion of AD [17,50].

Being in the 40-49 age group was found to be the second strongest variable influencing ATAD. These results can be attributed to the fact that ages 40-49 are the early stage of middle age, the period when individuals experience the aging of their parents’ generation, child-rearing, and economic responsibilities simultaneously [2], and gradually form perceptions about making end-of-life decisions and preparation for old age [3,4]. In particular, a high level of interest in AD as well as a high level of acceptance of AD in the 40-49 age group may be attributed to the fact that although they are in a life stage when their own health is relatively good, they are highly likely to indirectly experience decision-making regarding their parents’ illness or death. These results are partially different from those of the study by Ryu [23] and the study by Yeom [51], which reported that ATAD was more positive with increasing age, but the results suggest that ATAD is not necessarily formed only in old age but can also be formed and have significance in early middle age. In addition, the results of this study are not consistent with the study by Kwon and Kim [38], which reported that age did not have a significant effect on ATAD. Meanwhile, Suh and Kim [18] reported that age was not a variable affecting ATAD, but that the score for ATAD was higher in the 40-45 age group, compared to the 50-59 and 60-69 age groups. These results of the study by Suh and Kim [18] can be interpreted as supporting the results of this study.

Furthermore, considering that prior studies by Kim et al. [52], Ha and Gu [53], and Ko et al. [17] suggested that a person should prepare AD when he or she is young and healthy, it is thought that if individuals begin to form awareness and attitudes regarding AD and prepare AD in their 40s, it will have a positive effect on ATAD, but longitudinal follow-up research is needed to investigate the causal relationship.

Awareness of AD was found to be the third variable influencing ATAD. These results are similar to the findings of the study by Ryu [23], which surveyed knowledge and ATAD among 131 people from the general population, and found that awareness of AD was linked to positive ATAD and the intention for withdrawal of life-sustaining treatment. In addition, the results of this study are also similar to the findings of the study by Kwon and Kim [38] and the study by Suh and Kim [18], which reported that a higher level of knowledge of AD was linked to more positive perceptions of a good death and more positive ATAD. In the light of the findings described above, it is believed that systematic promotional activities and regular educational programs designed to raise awareness of the concept and necessity of AD and increase knowledge about AD can contribute to strengthening positive ATAD and promoting the practice of completion of AD. Meanwhile, a study by Hong and Lee [16] surveyed 60 adults residing in a region regarding awareness of AD and ATAD, and found that the level of awareness of AD was 8.3%, but the level of ATAD was very high at 86.6%. Although the results of Hong and Lee [16] can be interpreted as indicating that the level of awareness of AD does not significantly influence ATAD, regional differences regarding these variables cannot be ruled out, so further research is needed to comparatively analyze regional differences regarding the relationship between awareness of AD and ATAD.

SE was found to be the fourth variable affecting ATAD. These results are consistent with the study by Ha [8], which reported that since people with a high level of SE tend to try to have control over their life and death, SE is a variable that positively influences ATAD. The results of this study are also in alignment with the findings of the study by Ha and Gu [53], which reported that higher SE was associated with a stronger will to face one’s last moments of life with dignity and more positive ATAD. In addition, Nakakita et al. [37] reported that SE is a key topic in mental health and health care, and it can influence well-being, acceptance of illness, and anxiety reduction. Further, the study by Orth and Robins [5] reported that a high level of SE is a significant factor affecting the entire domain of self-initiated life. It is believed that the above previous findings can be interpreted as showing that SE may lead to reflecting one’s strong will for a good death [21] in the intention to sign an AD. Regarding enhancement of SE among middle-aged adults, it is believed that emotional education programs for promoting self-understanding and self-acceptance, self-development through lifelong learning, and health management education programs can be utilized as customized strategies for enhancing SE in middle-aged adults, a period marked by significant changes in physical, social, and mental roles

The frequency of thinking about organ donation was found to be the fifth variable affecting ATAD. There are limitations to the comparative analysis of related research findings due to the lack of prior studies to investigate whether the frequency of thinking about organ donation is a variable influencing ATAD. However, considering that frequently thinking about organ donation was associated with higher scores for ATOD, ATE, and ATAD, it is presumed that a high frequency of thinking about organ donation improves awareness of organ donation, which leads to the practice of organ donation, and eventually positively influences ATAD related to the pursuit of a dignified death. In this regard, the results of this study are meaningful results in line with the findings of the study by Son et al. [54], which reported that experience of discussing organ donation with others and expression of the intention to donate organs had a positive impact on practicing organ donation, and that the intention to sign an AD and positive ATAD were also factors influencing organ donation. Therefore, it is believed that application of a continuous, customized education program tailored to each stage of the life cycle, which can contribute to the systematical establishment of forward-looking thoughts, awareness, and practice regarding organ donation, will have a positive impact not only on ATAD but also on completion of AD among middle-aged people.

Religion was found to be the sixth variable affecting ATAD. In this connection, the study by Kang and Ju [55] surveyed ATAD in 193 people aged 40 or older from the general population, and reported that there was a significant difference in ATAD in the religious group, and that 64% of the participants wanted to die a peaceful death, while 48% wanted to die a dignified death without pain or suffering. In addition, in a study of 142 patients with myocardial infarction by Suh and Kim [18], the group with religion showed a higher score for ATAD. Based on the findings of previous studies, it can be inferred that religious beliefs are a factor positively influencing ATAD. On the other hand, the study by Colenda and Blazer [56] found that strong religious and spiritual beliefs were associated with conservative attitudes toward advance care planning (ACP) and AD. Moreover, the results of the study by Choi and Rhee [57] and the study by Ha and Gu [53] suggested that religion did not have a significant impact on ATAD. Further, the study of 950 Portuguese from the general public by Macedo et al. [48] reported that agnostics/atheists showed more positive ATAD. These findings suggest that religion is not an absolute variable affecting completion of AD, indicating that further research is needed to clarify the relationship between religion and ATAD. However, the study by Yoon [42] found that the group with religion showed a favorable attitude toward organ donation, and the study by Ha [8] reported that acceptive perception of organ donation is a variable that has a positive effect on AD. In view of these findings, in order to expand and sublimate the public interest value of religious beliefs through AD, application of programs mediated by various religious beliefs may be used as an effective strategy to positively change or strengthen ATOD as well as ATAD.

In this study, six key variables influencing ATAD were identified, and as a result, it was found that there is an organic connection between ATOD and ATAD. When nurses plan educational programs for middle-aged adults, the above findings can serve as foundational data for composing a r the educational content that shows that AD is not a mere medical procedure but self-initiated end-of-life planning combined with altruistic values (organ donation). In particular, this research has nursing-related significance in that it expanded discussion on AD, which was previously focused on the elderly, to married middle-aged adults, who may need to make surrogate decisions regarding their parents’ deaths, and thereby provided practical grounds for the importance of community-based family-centered nursing.

Conclusions

This study is a cross-sectional descriptive survey study to investigate the impacts of SE, ATOD, and ATE on ATAD among married middle-aged adults residing in six regions including Seoul. As a result, ATOD, age (being in the 40-49 age group), awareness of AD, SE, frequency of thinking about organ donation, and religion were identified as variables influencing ATAD, and among these variables, ATOD were found to be the strongest influencing factor. In particular, it should be noted that there were significant differences in ATOD according to the experience of thinking about organ donation and the experience of thinking about euthanasia, and that ATOD was also positively correlated with SE, ATE, and ATAD. These results provide foundational data that suggests that it is necessary to raise awareness of organ donation and improve ATOD when developing educational strategies for improving ATAD and the completion rate of AD in the future. However, this study has limitations in generalizing its results to single middle-aged adults or middle-aged adults across all the regions in Korea, since its participants were limited to married middle-aged adults residing in specific regions. In addition, since the participants were limited to married middle-aged adults in Korea, there are limitations in applying the results of this study to groups with different racial and cultural characteristics. Therefore, follow-up research should be conducted by using a representative sample of the total middle-aged population drawn from expanded residential regions and by including multicultural middle-aged adults. Further, considering that middle age is the life stage that immediately precedes old age, follow-up research targeting the elderly should also be conducted.

References

• 1. Statistics Korea. 2023 Administrative statistics by life stage [Internet]. Seoul: Statistics Korea; 2024 [cited 2025 Aug 25]. Available from: https://kostat.go.kr/board.es?mid=a10301060700&bid=11895&act=view&list_no=434470
• 2. Infurna FJ, Gerstorf D, Lachman ME. Midlife in the 2020s: Opportunities and challenges. The American Psychologist. 2020;75(4):470–485. https://doi.org/10.1037/amp0000591ArticlePubMedPMC
• 3. Solhi M, Pirouzeh R, Zanjari N. Middle-aged preparation for healthy aging: A qualitative study. BMC Public Health. 2022;22:274. https://doi.org/10.1186/s12889-022-12715-xArticlePubMedPMC
• 4. Lachman ME, Teshale S, Agrigoroaei S. Midlife as a pivotal period in the life course: Balancing growth and decline at the crossroads of youth and old age. International Journal of Behavioral Development. 2015;39(1):20–31. https://doi.org/10.1177/0165025414533223ArticlePubMedPMC
• 5. Orth U, Robins RW. Is high self-esteem beneficial? Revisiting a classic question. The American Psychologist. 2022;77(1):5–17. https://doi.org/10.1037/amp0000922ArticlePubMedPMC
• 6. Jung YJ, Choi EJ. Development of a well-dying awareness scale for middle-aged adults in Korea: A mixed-methods study. Journal of Korean Academy of Nursing. 2025;55(2):285–300. https://doi.org/10.4040/jkan.24121ArticlePubMed
• 7. Bennett R, Savani S. Factors influencing the willingness to donate body parts for transplantation. Journal of Health & Social Policy. 2004;18(3):61–85. https://doi.org/10.1300/J045v18n03_04Article
• 8. Ha EH. The influence of university students' self-esteem and awareness of good death, organ donation, and euthanasia on awareness of advance directives. Journal of the Korea Academia-Industrial cooperation Society. 2025;26(4):412–424. https://doi.org/10.5762/KAIS.2025.26.4.412Article
• 9. Yoo CM. A decade of changes in two dimensional self esteem: A life course perspective. Health and Social Welfare Review. 2018;38(3):7–44. https://doi.org/10.15709/hswr.2018.38.3.7Article
• 10. Khalifa AM, Altisan HA, Albalawi MA. Public awareness, perception, and attitude towards organ donation and transplantation: Cross-sectional study among Ha'il City community, Saudi Arabia. Asian Journal of Medical Principles and Clinical Practice. 2022;5(2):41–52.
• 11. Korea Organ Donation Agency. 2024 Annual report [Internet]. Seoul: Korea Organ Donation Agency; 2024 [cited 2025 Aug 2]. Available from: https://www.koda1458.kr/newPr/annual.do
• 12. Bachmetjev B, Airapetian A, Zablockis R. Attitude of the Lithuanian public toward medical assistance in dying: A cross-sectional study. Healthcare. 2024;12(6):626. https://doi.org/10.3390/healthcare12060626ArticlePubMedPMC
• 13. Keis A, Aluoja A, Pisarev H, Uusküla A, Suija K. Attitudes towards euthanasia and assisted suicide: A cross-sectional study among physicians in Estonia. BMJ Open. 2025;15(6):e096450. https://doi.org/10.1136/bmjopen-2024-096450ArticlePubMedPMC
• 14. Korean Law Information Center. Act on decisions on life sustaining treatment for patients in hospice and palliative care [Internet]. Seoul: Korean Law Information Center; 2024 [cited 2025 Aug 25]. Available from: https://www.law.go.kr/
• 15. Vanderveken L, Schoenmakers B, Lepeleire JD. A better understanding of the concept “a good death”: how do healthcare providers define a good death? The American Journal of Geriatric Psychiatry. 2019;27(5):463–471. https://doi.org/10.1016/j.jagp.2018.12.017ArticlePubMed
• 16. Hong J, Lee M. Awareness of advance directives in Gangwon-do province's adults. Journal of The Korea Society of Computer and Information. 2020;25(5):169–178. https://doi.org/10.9708/jksci.2020.25.05.169Article
• 17. Ko HA, Hwang YY, Heo SK, Cho KA, Shin MS, Kim MY, et al. Perceptions and attitudes about advance care planning among healthcare professionals of cardiac care: A Q methodology study. Japan Journal of Nursing Science. 2025;22(1):e12641. https://doi.org/10.1111/jjns.12641Article
• 18. Suh MY, Kim JS. The relationship among death anxiety, knowledge and attitudes toward advance directives in middle-aged patients with acute myocardial infarction. Journal of Korean Gerontological Nursing. 2021;23(3):226–238. https://doi.org/10.17079/jkgn.2021.23.3.226Article
• 19. Puente KP, Hidalgo JLT, Herráez MJS, Bravo BN, Rodrı´guez JO, Guille´n VG. Archives of Gerontology and Geriatrics. 2014;58:20–24. https://doi.org/10.1016/j.archger.2013.07.009ArticlePMC
• 20. Rafferty KA, Cramer E, Priddis DA, Allen M. Talking about end-of-life preferences in marriage: Applying the theory of motivated information management. Health Communication. 2014;30(4):1–10. https://doi.org/10.1080/10410236.2014.889555ArticlePubMed
• 21. Kim SA, An JS, Suh KH. Predictors of preparedness for well-dying among middle-aged and older adults. Psychogeriatrics. 2024;24(6):1335–1346. https://doi.org/10.1111/psyg.13198ArticlePubMed
• 22. Febrero B, Almela-Baeza J, Ros-Madrid I, Arias JA, Ruiz-Manzanera JJ, Jiménez-Mascuñán MI, et al. The new age of organ donation-what factors have an influence on the attitude of older people? An attitudinal survey in southeastern Spain. International Journal of Environmental Research and Public Health. 2022;19(14):8524. https://doi.org/10.3390/ijerph19148524ArticlePubMedPMC
• 23. Ryu MH. Public knowledge and attitude towards advance directives and their intention towards withdrawing life-sustaining treatment. Journal of the Korea Academia Industrial Cooperation Society. 2022;23(7):297–307. https://doi.org/10.5762/KAIS.2022.23.7.297Article
• 24. Yoon HM, Choi YS, Hyun JJ. Current situation on signing advance medical directives and actual life-sustaining treatment given at a university hospital. Journal of Hospice and Palliative Care. 2011;14(2):91–100. https://doi.org/10.14475/kjhpc.2011.14.2.91Article
• 25. Chai HW, Ayanian JZ, Almeida DM. Non-spousal family support, marital status, and heart problems in adulthood. Psychology & health. 2021;36(8):1003–1020. https://doi.org/10.1080/08870446.2020.1809660Article
• 26. Baughman KR, Ludwick R, Audi A, Harlan L. Gender and couple status differences in advance care planning: A cross-sectional study. Palliative Care and Social Practice. 2024;18:26323524241287221. https://doi.org/10.1177/26323524241287221ArticlePubMedPMC
• 27. Penning MJ, Wu Z, Hou F. Childlessness and social and emotional loneliness in middle and later life. Ageing & Society. 2024;44(7):1551–1578. https://doi.org/10.1017/S0144686X22000824Article
• 28. Faul F, Erdfelder E, Buchner A, Lang AG. Statistical power analyses using G*Power 3.1: Tests for correlation and regression analyses. Behavior Research Methods. 2009;41(4):1149–1160. https://doi.org/10.3758/BRM.41.4.1149ArticlePubMed
• 29. Kang H. Sample size determination and power analysis using the G* Power software. Journal of Educational Evaluation for Health Professions. 2021;18:17. https://doi.org/10.3352/jeehp.2021.18.17ArticlePubMedPMC
• 30. Breckler SJ. Empirical validation of the affective, behavioral, and cognitive components of attitude. Journal of Personality and Social Psychology. 1984;47(6):1191–1205. https://doi.org/10.1037/0022-3514.47.6.1191ArticlePubMed
• 31. Lee JY, Nam SK, Lee MK, Lee JH, Lee SM. Rosenberg’s self-esteem scale: Analysis of item-level validity. The Korean Journal of Counseling and Psychotherapy. 2009;21(1):173–189.
• 32. Kwon HJ. Hospital nurses' attitudes concerning human tissue donation and transplantation [master's thesis]. [Seoul]: Kyung Hee University; 2009. 82 p.
• 33. Kim AK. Development of a scale to measure attitude euthanasia by Korean nurses. Journal of Korean Academy of Fundamentals of Nursing. 2001;8(1):95–104.
• 34. Lee HL, Park YH. Attitudes toward advance directives of older adults using senior centers. Journal of Korean Gerontological Nursing. 2014;16(2):160–169.Article
• 35. Johns R. One size doesn’t fit all: Selecting response scales for attitude items. Journal of Elections, Public Opinion & Parties. 2005;15(2):237–264. https://doi.org/10.1080/13689880500178849Article
• 36. Polit DF, Beck CT, Owen SV. Is the CVI an acceptable indicator of content validity? Appraisal and recommendations. Research in Nursing & Health. 2007;30(4):459–467. https://doi.org/10.1002/nur.20199Article
• 37. Nakakita M, Oya S, Kubota N, Toyabe T, Nakatsuma T. Relationships between self-esteem and personal attributes, income, consumption, and assets: Japanese panel study. European Journal of Investigation in Health, Psychology and Education. 2025;15(5):78. https://doi.org/10.3390/ejihpe15050078ArticlePubMedPMC
• 38. Kwon YE, Kim SY. Middle-aged adult women's good death awareness, attitudes and knowledge of the advance directives. The Journal of Next-Generation Convergence Technology Association. 2024;8(2):384–392. https://doi.org/10.33097/JNCTA.2024.08.2.384Article
• 39. Nurani GA, Lee YH. The facilitation of online learning for middle-aged employees. Journal of Systemics, Cybernetics and Informatics. 2024;22(6):124–145. https://doi.org/10.54808/JSCI.22.06.124Article
• 40. Krupic F. The impact of religion and provision of information on increasing knowledge and changing attitudes to organ donation: An intervention study. Journal of Religion and Health. 2020;59:2082–2095. https://doi.org/10.1007/s10943-019-00961-0ArticlePubMedPMC
• 41. Irving MJ, Tong A, Jan S, Cass A, Rose J, Chadban S, et al. Factors that influence the decision to be an organ donor: A systematic review of the qualitative literature. Nephrology dialysis transplantation. 2012;27(6):2526–2533. https://doi.org/10.1093/ndt/gfr683Article
• 42. Yoon SM. Interaction effects of religiosity level on the relationship between religion and willingness to donate organs. Religions. 2019;10(1):8. https://doi.org/10.3390/rel10010008Article
• 43. Inglehart RC, Nash R, Hassan QN, Schwartzbaum J. Attitudes toward euthanasia: A longitudinal analysis of the role of economic, cultural, and health-related factors. Journal of Pain and Symptom Management. 2021;62(3):559–569. https://doi.org/10.1016/j.jpainsymman.2021.01.009ArticlePubMed
• 44. Jansen NE, Gardiner D. Results of kidney transplantation from donors following euthanasia in the Netherlands: Benchmarking science and ethical challenge. Transplant International. 2024;37:13806. https://doi.org/10.3389/ti.2024.13806ArticlePubMedPMC
• 45. Yoo HI, Lee YH. Middle-aged adults' attitudes toward dignified death and advance directives. and knowledge of advance directives. Hospital Nurses Association. 2020;26(1):86–96. https://doi.org/10.22650/JKCNR.2020.26.1.86Article
• 46. Wagner E, Marckmann G, Jox RJ. Coincidence of advance directive and organ donor consent: What do the persons concerned want? A survey of German elderly citizens. Gesundheitswesen. 2020;82(12):977–983. https://doi.org/10.1055/a-0837-0882ArticlePubMed
• 47. Robinson L, Paes P. Advance care planning. Clinical Medicine. 2025;25(4):100339. https://doi.org/10.1016/j.clinme.2025.100339ArticlePubMedPMC
• 48. Macedo JC, Castro L, Nunes R. Attitudes of the Portuguese population towards advance directives: an online survey. BMC Medical Ethics. 2024;25(1):40. https://doi.org/10.1186/s12910-024-01043-xArticlePubMedPMC
• 49. Vincent BP, Kumar G, Parameswaran S, Kar SS. Knowledge, attitude, and perception on organ donation among undergraduate medical and nursing students at a tertiary care teaching hospital in the southern part of India: A cross-sectional study. Journal of Education and Health Promotion. 2019;8(1):161. https://doi.org/10.4103/jehp.jehp_439_18ArticlePubMedPMC
• 50. Sedini C, Biotto M, Crespi Bel'skij LM, Moroni Grandini REM, Cesari M. Advance care planning and advance directives: An overview of the main critical issues. Aging Clinical and Experimental Research. 2022;34:325–330. https://doi.org/10.1007/s40520-021-02001-yArticlePubMed
• 51. Yeom EY. The influence of good death awareness and knowledge of advance directives on attitude toward advance directives in middle-aged adults. Journal of the Korea Contents Association. 2020;21(2):676–685. https://doi.org/10.5392/JKCA.2021.21.02.676Article
• 52. Kim KS, Kim SM, Hong SW, Kim JS. The evaluation of the Korean advance directives (K-AD). The Korean Journal of Hospice and Palliative Care. 2016;19(2):109–118. https://doi.org/10.14475/kjhpc.2016.19.2.109Article
• 53. Ha EJ, Gu MO. Factors affecting intention of signing an advanced directives in cancer patients. Journal of Korean Academy of Fundamental of Nursing. 2021;28(1):121–132. https://doi.org/10.7739/jkafn.2021.28.1.121Article
• 54. Son MS, Kang IS, Jeon JH. Factors influencing will of brain death organ donation among university students. The Korean Society of Health Service Management. 2018;12(4):191–202. https://doi.org/10.12811/kshsm.2018.12.4.191Article
• 55. Kang KJ, Ju SJ. Ethical attitudes, perceptions of DNR and advance directives of general population. Journal of Korean Academy of Psychiatric and Mental Health Nursing. 2014;23(2):113–123. https://doi.org/10.12934/jkpmhn.2014.23.2.113Article
• 56. Colenda CC, Blazer DG. Review of religious variables in advance care planning for end-of-life care: Consideration of faith as a new construct. The American Journal of Geriatric Psychiatry. 2022;30(7):747–758. https://doi.org/10.1016/j.jagp.2021.11.014ArticlePubMed
• 57. Choi JW, Rhee YJ. Knowledge and attitudes toward advance directives among middle-aged women. Journal of Hospice and Palliative Care. 2021;24(2):74–84. https://doi.org/10.14475/jhpc.2021.24.2.74ArticlePubMedPMC

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