Knowledge, attitudes and willingness to organ donation among the general public: a cross-sectional survey in China

Background The purpose of this study is to assess the level of knowledge, attitudes, and willingness to organ donation among the general public in China. Methods The study population consisted of 4274 participants from Eastern, Central and Western China. The participants’ knowledge, attitudes and willingness to organ donation were collected by a self-designed questionnaire consisting of 30 items. Knowledge is measured by 10 items and presented as a 10 point score, attitudes is measured by 20 items using a 5-step Likert scale and total score ranged between 0 and 80; while the willingness to donate is assessed as binary variable (0 = No; 1 = Yes). A logistic regression model was used to assess the association of knowledge and attitudes with willingness to organ donation, controlling for demographic and socioeconomic confounders. Results The questionnaire response rate was 94.98%. The mean score (± SD) of the general public’s knowledge to organ donation was 6.84 ± 1.76, and the mean score (± SD) of attitudes to organ donation was 47.01 ± 9.07. The general public’s knowledge and attitudes were the highest in Eastern China, followed by West and Central China. The logistic regression model indicated a positive association between knowledge and the willingness to organ donation (OR = 1.12, 95%CI: 1.08, 1.17; P < 0.001); attitudes were also positively potential determinant of more willingness to organ donation (OR = 1.08, 95%CI: 1.07, 1.09; P < 0.001). Conclusions Knowledge and attitudes were found to be positively associated with the Chinese general public’s willingness to organ donation. Knowledge about the concept of brain death and the transplant procedure may help raise the rate of willingness to organ donation. Supplementary Information The online version contains supplementary material available at 10.1186/s12889-022-13173-1.

Knowledge and attitudes towards organ donations are determinants of the willingness to donate an organ. In an online survey of 1945 Intensive Care Unit (ICU) nurses, health science students and non-health science students in Austria, Stadlbauer V et al. showed that the study participants knowledge of Austrian organ donation legislation was high [8]. In a cross-sectional study survey of 1275 hospital medical and non-medical staff in 15 Japanese medical facilities, Murakami M et al. found high knowledge about organ donation and transplantation was associated with willingness to become an organ donor [9]. Further, in a survey of 724 physicians of different specialties in the USA, Alkhatib AA et al. showed physicians who were identified as donors were more aware about issues related to organ shortage [10].
In China, organ transplantations have been conducted since the 1960s and have saved tens of thousands of patients. Today, China is the country with the second highest number of organ transplantations worldwide and completed 6,302 organ donations in 2018 [11,12]. Yet, there is still a shortage of organ donors [13]. A survey among 373 health professionals from 7 hospitals in Dalian and 1 hospital in Chaozhou in China, showed that health professionals lacked knowledge about organ donation on the sector where to donate organ and the procedure of donation [14]. Attitudes of visitors at adult intensive care unit to organ donation is low in Hong Kong [15]. To date, research is limited to studies with small sample size and lacks geographic diversity.
The aim of this study is to assess the knowledge, attitudes, and willingness to organ donation among the general public in China. An analysis of the knowledge and attitudes towards organ donation in the general Chinese public is required to improve the knowledge about organ donation as well as inform policy and legislation aimed at increasing the number of organ donation.

Study population
We conducted a survey among residents in 3 regions of China-Eastern, Central and Western China [16], between 25 th October and 26 th December 2019. We used a multistage stratified sampling method. At the first sampling stage, we used the province as the sampling unit, we selected Zhenjiang (Eastern China), Henan (Central China) and Shaanxi (Western China). At the second stage, we sampled one city by province, namely Hangzhou, Zhengzhou and Xi'an. At the third stage, we selected at least 2 districts per city with a final inclusion of 9 districts. At the final stage, we took a convenience sample of individual residents within the community or town. The formula for calculating the sample size for this study is: N is the sample size; µ 2 α/2 refers to the statistic of 1.96 for a two-sided test with a confidence interval of 95%, δ is the permissible error and P is the rate of willingness to donate organs. Based on a willingness to donate of 18.8% to 47.9% [17,18], an error ( δ ) of 3%, α = 0.05, 1 − β = 90%, and an expected 20% nonresponse rate, we estimated the sample size for each site of this study to be between 781 and 1278. In this study, we actually recruited a total of 4305 participants.

Research instruments
We employed a self-designed questionnaire based on previous researches [19][20][21][22][23][24] consisting of 4 parts. (1) The participants' demographic and socioeconomic characteristics, including gender, age, education, marital status, employment, monthly income. (2) Participants' knowledge of organ donation which includes ten statements with a true/false response option. For items 1 to 7 and 10, the true answer scored 0, whereas the false answer would score 1; for items 8 and 9, the opposite applied. Hence, the sum of the responses represents the total score of knowledge of organ donation and ranges between 0 and 10. (3) Further, we collected information on participants' attitudes towards organ donation with 20 items using a 5-step Likert scale ranging from fully agree, mostly agree, neutral, mostly disagree, fully disagree. Items 11 to 14 and 30 were scored in declining order where 'fully agree' was equal to 4 and 'fully disagree' was equal to 0, items 15 to 29 were scored inversely and 'fully agree' was scored as 0. The total score of attitudes towards organ donation ranged between 0 and 80. Moreover, the attitudes were grouped in three categories: life view (item 11 to 18), family value (item 19 to 21), and evaluation (item 22 to 30). (4) Lastly, we collected the participants' willingness to organ donate by asking ' Are you willing to donate your organs?' which generated a binary variable (0 = No; 1 = Yes). The specific questionnaire is showed in the appendix (additional file 1). The questionnaire was developed in the following steps: 1) based on previous literature and research, we drafted the first version of the questionnaire, and then organised two rounds of expert consultations, inviting six experts from the subject areas of epidemiology, health statistics and public administration in each round to revise the content of the questionnaire in terms of necessity, feasibility, and logic. 2) A pilot survey was conducted with a sample of 100 residents in Zhengzhou city and Xi ' an city, respectively; 3) before performing the data analysis, we tested the reliability and validity of questionnaire [25,26]. The Cronbach α for the questionnaire was 0.740 and internal consistency of instruments was deemed satisfactory. Exploratory factor analysis in structural validity was used to support the validity of the questionnaire. The Kaiser-Meyer-Olkin (KMO) statistic was calculated as 0.862, which passed the Bartlett's test of sphericity (χ 2 = 5556.84, P < 0.001), indicating that this data was well suited for factor analysis. Finally, a principal component analysis was carried out to delete and retain entries.

Quality control
Local investigators were instructed on the study procedures and trained by experts from the Liverpool School of Tropical Medicine, Wenzhou Medical University, Hangzhou Normal University, Xi'an Jiaotong University and Zhengzhou University on how to conduct interviews with study participants. We unified inquiry methods before the formal investigation. Regular assessments and examinations were performed during the entire investigation period.

Statistical analyses
The questionnaire data were entered into the EpiData 3.1 software (developed by EpiData Association, Odense, Denmark), we used a double entry method for all data. All questionnaire data were checked for outliers prior to data analysis, outliers of all variables used in this study and missing value of outcome variable were dropped. Continuous variables were summarized as means with standard deviations, and categorical variables were summarized as counts and percentages. We compared differences in knowledge, attitudes, and willingness to organ donation by conducting chi-squared test. We assessed the relationship of knowledge and attitudes with the willingness to organ donate using binary logistic regression models. We controlled for the following confounding factors: participants' gender, age, marital status, education, and monthly income. We present the odds ratios (ORs) with 95% confidence intervals (CIs) and a two-tailed p-value of < 0.05 was considered statistically significant. The statistical analyses were performed in SAS 9.4 (SAS Institute, Cary, NC, USA) and figures were made using the R studio software.

Basic information of participants
At baseline we recruited 4500 participants from 3 sites into the study of which 4274 finished the questionnaires, resulting in response rate of 94.98%. Table 1 shows the demographic and socioeconomic characteristics of the study participants by region. Participants were recruited in similar numbers from each region, namely 32.59% (1393) from Western China, 32.64% (1395) from Central

Knowledge of organ donation
The knowledge about organ donation mean score (± SD) was 6.50 ± 1.62 out of 10, participants that were willing to organ donate had a higher score as compared to the ones not willing to donate, 6.71 and 6.32, respectively ( Table 2). Most participants were aware of the following items 4 and 3: not any doctor can determine brain death (88.53%) and it is correct that living organs can only be donated to immediate family members (80.35%). More than 60% of the participants chose the correct definitions related to organ donation (item 1, 60.90%) and brain death (item 2, 64.87%). A minority of the participants did not agree with the statement that 'organ removal must be performed only after brain death is determined' (item 5), indicating a lack of knowledge about the donation procedure. Participants that were willing to donate organs were more likely to know about regulations about the age of an organ donor (item 7) as compared to participants who were not willing to donate (71.49% vs 61.33%, P < 0.001). However, for items 1 to 4, 8 and 9 participants that were willing to donate scored lower compared to participants that were not willing to donate in particular for items (from) compared with the participants who were not willing to donate organs (P < 0.001).

Attitudes to organ donation
The overall mean (± SD) score of attitudes to organ donation in this study was 47.32 ± 9.55, among participants who were willing to donate organs the attitude score was higher as compared to participants not willing to donate ( Table 3, P < 0.001). Figure 1 showed participants willing to donate organs were more likely to fully agree with the views on organ donation such as 'organ donation can save lives and benefits mankind' (item 11; 70.14%) and 'organ donation is a new form of life' (item 12; 57.93%). On the other hand, 44.31% of participants that were willing to donate fully disagreed with the statement: 'I think signing an organ donation card is an auspicious thing and it will bring misfortune' (item 15), 47.28% disagreed with 'donating

Association of knowledge and attitudes with willingness to organ donation
The association of knowledge about organ donation and the willingness to organ donate is show in Fig. 2. The logistic regression model shows that the sum of knowledge items had the strongest positive association with the willingness to organ donation, among the factors including participants' residence, gender, age, education, employment, marital and economic status analyzed in this study. The OR of the association of knowledge and willingness was 1.12 (95%CI: 1.08, 1.17; P < 0.001), indicating that the knowledge score increases by 1 point, the odds of willingness to organ donation would increase by 12%, meaning more participants will be a potential donor. In addition, the logistic regression model indicated that the attitudes score (OR = 1.08, 95%CI: 1.07, 1.09; P < 0.001) was positive determinant of willingness to organ donate (Fig. 3) when controlling for other factors.

Assessment of the moderating effect
Correlations between variables were tested in the Table 4. Without exception, they were all below 0.61. The moderating effect of knowledge on the attitude-willingness link and gender on the attitude-willingness link was tested by moderated regression analysis (Table 5). At the first step, the total scores of attitude and knowledge were entered as independent predictors of willingness to organ donation when controlling for region, residence, gender, age, marital status, education, employment and monthly income. Table 5 shows that when the total score of attitude towards organ donation is increased by 1 score, the odds of willingness to donates one's organs would increase by 8.0% (OR = 1.080, P < 0.001). In the second step, their interaction term was entered as independent predictors when controlling for other factors. The odds of willingness to organ donation would increase only by 0.4% (OR = 1.004, P < 0.001) when the interaction term (total score of knowledge × total score of attitudes) is increased by one unit.
In the third step, the total score of attitude and gender were entered as independent predictors of willingness to organ donation when controlling for total score of knowledge, region, residence, gender, age, marital status, education, employment, and monthly income. Compared with male participants, the odds of willingness to partake in organ donation were nearly 1.3 times higher for female participants (OR = 1.253, P = 0.002). When the    total score of attitude toward organ donation increases by 1 score, the odds of willingness to organ donation would increase by 7.9% (OR = 1.079, P < 0.001). In the fourth step, their interaction term was entered as independent predictors. Compared with male participants, the odds of willingness to partake in organ donation would increase by 1.5% for female when the total score of attitudes is increased by 1 score (OR = 1.015, P < 0.001). Moderated regression analyses revealed that there was an interaction effect on willingness to organ donation between knowledge and attitude, gender and attitude.

Discussion
The number of organs donated in China has risen rapidly over the past decade but the need is not met which presents a major obstacle to saving lives. This study is the latest survey of the general public's knowledge, attitudes, and willingness to organ donate across geographical settings in Western, Central and Eastern China. We provide an important perspective on organ donation and the barriers to willingness to donate related to knowledge and attitudes.

Main findings
In this study, the general public's rate of willingness to organ donation was 47.45%. For the domestic public, this rate was similar to the rate in Nanning City (47.92%) [18], higher than the rate in Ji'nan city (46%) [27], Zhejiang Province (18.8%) [17] and Northwest China (29.5%) [28]; Compared with foreign data, this rate was higher than the rate in Japan (41.9%) [29], and lower than the rates in Syria (62%) [30] and in the Middle East (49.8) [31]. Unsurprisingly, the rate of the general public's willingness to donate organs was lower than that previously reported in Chinese health professionals (49.3%) [14], Chinese transplantation patients and their caregivers (62.7%) [32], medical students in Spain (79%) [33], in Germany (63.5%) [34] and Jimma University (58.1%) [35]. All things considered, general public's willingness to donate organs in this study is not particularly high and targeted measures should be implemented by the policymakers and scientists to improve the situation.
This study shows that higher knowledge about organ donation was associated with the willingness to become an organ donor, which is consistent with previous studies conducted by Figueroa [36,37]. Other studies conducted in Australia, Korea, Niger and Ghana showed no such association [38][39][40][41]. These discrepancies might be related not only to the measurement of knowledge (the content and number of questions), but also to different cultural and country specific factors such as traditional values, religious beliefs, compensation mechanisms, institutional credibility and ideals [42]. The relationship between knowledge and willingness to organ donation needs more research to verify. In this study, 10 questions were designed to determine general public's basic knowledge about organ donation. Only 60.90% of the general public identified the right meaning of brain death, and 42.35% of general public were familiar with the right procedure of organ removal. Therefore, increasing knowledge about the concept of brain death and the transplant procedure may help raise the rate of willingness to organ donation in China. Our study also indicated that attitudes were positively associated with the willingness to organ donation, which was confirmed with other studies [21]. Raising public's awareness of organ donation Table 5 Moderated regression analyses to predict whether individual is willing or not willing to donate organs, when controlling for other confounders

Regression analyses in
Step 1 and step 2 controlled for region, residence, gender, age, marital status, education, employment, and monthly income.
Step 3 and step 4 controlled for total score of knowledge, region, residence, gender, age, marital status, education, employment, and monthly income Variable OR 95%CI P

Lower Upper
Step 1  [46,47]. The present data provide some evidence for the moderating role of knowledge and gender in predicting willingness to organ donation. More specifically, the association between attitudes towards organ donation and willingness to donate organs appeared to be stronger for participants with high total knowledge scores compared to those with low total knowledge scores. Effective measures to increase the willingness to donate organs should not only improve the public's attitude towards organ donation, but also increase their knowledge about organ donation. Additionally, the link between attitudes toward organ donation and willingness to organ donation appeared to be stronger for women compared to men.
The influence of gender may be related to gender stereotypes. According to this notion, women should feel a strong moral obligation to become a potential organ donor and they have a stronger sense of compassion than men [48]. The results of our study also suggested a lower rate of willingness to donate organs among those who were married, which was consistent with Abukhaizaran and Yan's studies [49,50], but in contrast to Iliyasu's study [51]. This association remains to be explored by further research.

Limitations
This study has some limitations. Firstly, this is an observational study and the confounders of willingness to organ donation included in this study are limited by the pre-specified questions in the surveys. There could be some potential unobserved confounding factors (related policies such as presumed consent law and allocation priority were found to be effective measures to increase organ donation [52][53][54]) we did not control for in the logistic model. Secondly, this study reports the influence of general public's knowledge and attitudes on willingness to organ donation based on a quantitative study, more evidence based on qualitative studies and randomized controlled trials are needed to support the results comprehensively. Nevertheless, this study forms an important baseline step for future studies.

Conclusions
In summary, knowledge and attitudes were found to be positively associated with Chinese general public's willingness to organ donation and their attitudes were less hindered by Chinese traditional values. Besides, our study suggested that a donation education program focusing on increasing knowledge about the concept of brain death and the transplant procedure may help raise the rate of willingness to organ donation in China, and ultimately to reduce the imbalance between the supply and need for organ transplantation.