Saudi Journal of Kidney Diseases and Transplantation

REVIEW ARTICLE
Year
: 2021  |  Volume : 32  |  Issue : 5  |  Page : 1201--1213

Application of theory of planned behavior on organ donation behavior: A systematic review


Marzieh Latifi1, Jandir Pauli2, Sanaz Dehghani3, Marzeyeh Soleymani Nejad4,  
1 Sina Organ Procurement Unit, Tehran University of Medical Sciences, Tehran, Iran
2 Post Graduate Program in Business Administration, IMED, Passo Fundo, Brazil
3 Sina Organ Procurement Unit, Tehran University of Medical Sciences, Tehran, Iran; Post Graduate Program in Business Administration, IMED, Passo Fundo, Brazil
4 Independent Researcher, Tehran, Iran

Correspondence Address:
Marzeyeh Soleymani Nejad
Independent Researcher, Tehran
Iran

Abstract

Organ donation saves lives and improves the quality of life. There is a shortage of organ donors worldwide. Behavior theories, such as the theory of planned behavior (TPB), help identify the antecedents of organ donation behavior and design effective interventions. The TPB suggests that intention is driven by constructs: attitude, subjective norm, perceived behavioral control (PBC), and intention. TPB can help improve organ donation behavior. This study aimed to analyze TPB-based interventions on Organ donation. Relevant studies were identified searching electronic databases, i.e., PubMed, Scopus, Science Direct, and Google Scholar from January 1, 2000 to February 30, 2020. None MeSH terms in title or abstract were searched, including: “theory of planned behavior*” and “Tissue donation” or “Tissue procurement” or “Organ procurement system” or “Organ procurement” or “Organ donation.” Two authors independently reviewed the full texts and extracted all critical data from the included studies. Seventeen studies were assessed as having a reasonable methodology design. Studies show that TPB-based interventions can improve organ donation. Among TPB’s constructs, PBC is the moderator and the determinant of organ donation behavior which its determination is different in different cultures. Attitude, subjective norms, moral norms, and anticipated regret should be considered in related interventions plus PBC. Increasing knowledge can facilitate organ donation behavior. Removing related cultural issues, removing fear due to misunderstanding of Brain death, improving trust, and improving moral values have effects on the behavior of organ donating.



How to cite this article:
Latifi M, Pauli J, Dehghani S, Nejad MS. Application of theory of planned behavior on organ donation behavior: A systematic review.Saudi J Kidney Dis Transpl 2021;32:1201-1213


How to cite this URL:
Latifi M, Pauli J, Dehghani S, Nejad MS. Application of theory of planned behavior on organ donation behavior: A systematic review. Saudi J Kidney Dis Transpl [serial online] 2021 [cited 2022 May 25 ];32:1201-1213
Available from: https://www.sjkdt.org/text.asp?2021/32/5/1201/344739


Full Text



 Introduction



Although organ donation could save lives and improve the quality of life, there is a shortage of organ donors worldwide.[1] The previous literature shows that most people are reluctant to posthumous organ donation.[2] Some reasons are mentioned for such reluctance, including a lack of body integrity, distrust of the medical system, and denial of family members or close friends.[3],[4],[5]

Focus on identifying psychosocial predictors of intentions and behaviors to communicate consent for organ donation via getting donor card or talking with the family,[6] has resulted in the development of decision-making models which use constructs of theory of planned behavior (TPB),[7] such as attitude and subjective norms.[8]

 Theory of Planned Behavior



TPB, an extension of the theory of reasoned action,[9] was emerged because of the original model’s limitations in dealing with behaviors over which people have incomplete volitional control.[7],[9] This theory, as an expectancy-value model, states that behavior is a consequence of one’s behavioral intention, and intention is a consequence of three conceptually determinants [Figure 1], including:{Figure 1}

Attitude toward the behavior; it refers to the degree to which a person has a favorable or unfavorable evaluation or appraisal of the behavior in questionSubjective norm; it refers to the perceived social pressure to perform or not to perform the behaviorPerceived behavioral control (PBC); it refers to the perceived ease or difficulty of performing the behavior and it is assumed to reflect experience as well as anticipated impediments and obstacles.

The stronger attitudes, subjective norms, and PBC, the greater should be behavioral intentions and ultimately behavior. The relative importance of attitude, subjective norm, and PBC in the prediction of intention vary across behaviors and situations. Thus, in some TPB applications attitudes have a significant impact on intentions, in others attitudes and have a significant impact on intentions, and in others attitudes, PBC, and subjective norms make independent contributions.[7]

Godin et al, and Hyde and White studies support the use of TPB to understand people’s decisions to join a donor registry/signing a donor card[10],[11] or talking with the family [12],[13] and explain up to 60% of the variance in people’s consent communication intentions. The success of retrieval is hugely dependent on the levels of knowledge[14],[15],[16] and attitude of public people,[8],[17] also altruistic desires to help others,[18] patient and family demographics,[19],[20] cultural background and religious beliefs,[21],[22] ethnicity,[23] and media.[24],[25],[26],[27]

Regarding the TPB constructs effects on organ donation’s intention and behavior [Figure 1], this study aims to review studies which have used TPB on organ donation.

 Methods



Relevant studies were identified searching electronic databases, i.e., PubMed, Scopus, Science Direct, and Google Scholar, from January 1, 2000, to February 30, 2020 [Figure 2].{Figure 2}

Inclusion criteria were including publishing in English, measuring organ donation intentions or behavior, direct measuring of attitudes, subjective norms, and perceived behavior control. Exclusion criteria were including publishing in languages other than English, conference abstracts, not peer-reviewed studies (book, unpublished thesis), and review studies (letters, systematic reviews, commentaries).

None MeSH terms in title or abstract were searched, including: “theory of planned behavior*” and “Tissue donation” or “Tissue procurement” or “Organ procurement system” or “Organ procurement” or “Organ donation” The search was limited to human participants.

Data extraction and quality assessment

Two authors (M. L. and M. S.) independently reviewed the full-texts and extracted all critical data from the included studies, including author, country of study, year of publication, study design, sample size, participant characteristics, study duration, intervention type, intervention content, statistical methods, and study findings and outcomes measured. Furthermore, any association between donation intentions, attitudes, subjective norms, perceived behavioral control were assessed. The quality of studies was accessed.

 Results



Search results

Searching by the keywords in the first step generated 1413 studies. In the second step, full-text articles were obtained of studies meeting the eligibility criteria following title and abstract screening. Eligibility was assessed through full-text screening. At the title and abstract screening level, the eligibility should be reached with both the reviewers (M. L. and M. S.). A total of 17 studies were included in the final review.

Overview of the included studies

Characteristics of the included studies are described in [Table 1]. Five studies were conducted in the United States, four in Australia, one each in Canada, Taiwan, UK, Iran, Austria, and Brazil. Two of the studies work in Korea and USA together, and one of the work in Japan, Korea, and the USA together. Fifteen studies were cross-sectional,[10],[12],[13],[29],[31],[32],[33],[34],[35],[36],[37],[38],[39],[40] one study was interventional,[30] and one study was mixed method.[28] In all studies, 10118 people participated. Nine studies were carried on students, two on the medical staff, and six on public people.{Table 1}

Summary of the findings

Knowledge about organ donation was the most common facilitator to becoming a Registered organ donor.[41],[42]

Fear[11],[10] and lack of knowledge[31],[40] were the most common barriers. Mistrust and social justice themes,[40] and misconceptions about the donation process[10] were infrequently referenced as barriers to becoming a registered organ donor.[11]

According to Stephenson et al,[37] body integrity, age, and gender in some cultures influence on donation decisions strongly.[34] Religiosity had an effect on willingness to donate.[40]

Based on Godin et al,[10] anticipated regret has an impact on organ donation as a moderating factor.

Theory of planned behavior relationships across the studies

Highly significant differences were measured between both conditions for the social norms and attitude toward organ donation.[38] The strongest correlates of registering and discussing intentions were including subjective norms and moral norms.[36]

Significant linear positive correlation between behavioral intention and attitude,[13],[29],[35],[30] subjective norms and PBC were seen in some studies. PBC was more correlated with students’ intention for getting organ donation cards.

Role of theory of planned behavior structures in the behavior

Attitude and social norms[12] predicted intention to become a donor for American respondents, although attitudes toward donation had a weak positive relationship on intent to donate.[37] In the Bresnahan study, done in Korea, American and Japanese respondents exhibited more positive attitudes, more knowledge, and more behavioral intention to register as organ donors than either Japanese or Korean respondents.[12]

Ghaffari et al,[29] Britt et al,[34] and Park et al[43] showed that PBC is a moderator for TPB. According to Yun and Park that assess organ donation intention on Korean and American people, while subjective norms and PBC were more important than attitudes among Americans, PBC was more important than subjective norms and attitudes among Koreans.[33] On the other hand, subjective norms exerted a modest positive relationship on intentions to donate.[37] Attitudes and subjective norms were similarly related to Americans’ intentions to sign, subjective norms were more strongly related to Koreans’ intentions to sign than attitudes and PBC.[33] Attitudes and subjective norms were similarly related to Americans’ intentions to sign, subjective norms were more strongly related to Koreans’ intentions to sign than attitudes and PBC.[33]

Godin et al study showed that intention, PBC, moral norms, and past behavior were factors predictive of consent for posthumous organ donation.[10]

Intention was correlated with three dependent variables. The influence of age and gender was controlled as potentially confounding factors.[5] There were moderately strong positive attitudes and weak negative attitudes to organ donation and transplantation.[10] The study of Yun and Park[7] showed that attitudes were a stronger predictor among Americans than Koreans and PBC was a significant predictor only among Korean.

The findings of Newton et al suggest that conceptual overlap between moral norms and anticipated regret is more likely to occur among behaviors with obvious moral implications.[44]

Educational interventions’ effects

Lin et al[9] suggested that after TPB training, the nurses significantly changed their attitudes and behavior intentions on organ donation advocating.

 Discussion



According to the TPB, organ donation behavior can be triggered or prevented through the main constructs of TPB, including: attitude, subjective norms, and PBC. Furthermore, background factors, including individual factors, social factors, and information, affect organ donation. Some of these factors were considered in the studies, which can facilitate or prevent organ donation.

Facilitating factors of organ donation

Some studies[12],[37],[45],[46],[47] support the notion that social outcome expectations or subjective norms, defined as “important others to me,” have a positive impact on one’s intent to donate. According to Reubsaet et al,[47] social outcome expectations had the strongest positive influence on intention to donate. Also, discussions with other people about organ donation had positive effects on intent to donate, although the relationship was not as strong as that with social outcome expectation. Shih et al[46] suggested that subjective norms contribute to the family members’ decision to consent to organ donation. Their study shows that “encouragement from the donor’s close friends” was one of the influencing factors of the donor family to consent to their next of kin’s donation”. As illustrated in Morgan et al study,[45] among African-American family members, subjective norms significantly influenced both willingness to talk about organ donation and the willingness to donate organs.

Subjective norms also have an important role on the family decision to donate. In many Muslim countries in which there is opt-in law related to obtaining consent to deceased organ donation, not knowing about the donor’s decision may prevent the family to donate. If the donor talks about her/his decision it can improve organ donation.

Attitude is a significant predictor of support for organ donation.[12],[29],[33],[37],[48] Some sources of positive attitude are including personal satisfaction, feelings toward humanitarian aspect of donation and the honor of being a donor.[49] According to Bresnahan et al,[12] attitude predicted intention to become a donor for American respondents. Although, in Stephenson’s study et al[35] attitudes toward donation had a weak positive relationship on intent to donate. Studies on attitudes toward organ donations suggest that being aware of the wish of deceased, family would have positive attitude toward organ donation.[50],[51],[52] Yun and Park study[33] showed that attitudes were a stronger predictor among Americans than Koreans.

Godin et al study showed that intention, PBC, moral norms, and past behavior were predictive factors of consent for organ donation.[10] Ghaffari et al,[29] Britt et al,[34] and Park et al[43] showed that PBC is a moderator for organ donation. The study of Yun and Park[33] showed that PBC was a significant predictor only among Koreans rather than Americans.

Also, moral norms are predictive of consent for posthumous organ donation. Godin et al suggested that individuals who form intentions based on moral values are more likely to act on intentions to perform morally based behaviors.[10] Findings of Newton et al suggest that conceptual overlap between moral norms and anticipated regret is more likely to occur among behaviors with obvious moral implications.[44]

Anticipated guilt was in turn predicted by empathic concern and norms in the donor registration model and by empathic concern, attitudes, and norms in the family discussion model.[32]

Barriers of organ donation

According to Ghorbani et al, fear, religious beliefs, and belief in body integrity after death are the causes of rejection of organ donation.[53]

Based on Ryckman et al,[9] most religions support organ donation, but some of their followers do not know this which may affect their decision about organ donation. Therefore, those who are influenced by religion may regard their spiritual leaders highly when contemplating the decision to become an organ donor,[54] and some cultures are influenced by traditional religious and philosophical beliefs that may make them reluctant to donate their organs. Furthermore, patients may be reluctant to donate because the organ procurement process may seem to violate their religious and spiritual beliefs. Individuals who believe that religious norms toward organ donation are favorable may be more likely to become donors.[54] Therefore, convincing religious leaders can improve organ donation in society. Furthermore, if clinicians became more educated about these beliefs, a slight change in the procurement protocol may allow patients to donate their organs without violating their values.[55]

One of the reasons people reject to donate is the idea of losing bodily integrity in the case of organ donation, which may be related to their religiosity, as religion usually address the concepts of life after death. While most religions insist on the value of life savings. Therefore, education is needed in this area.

Fear and some beliefs about life after death are mentioned as barriers to organ donation in some studies.

One of the factors affect public belief related to organ donation is misinformation in this area.[56],[57]

The most important factor affecting one’s belief system is the tenet of Confucianism in which returning body after death in its original state is emphasized.[55]

Involving religious leaders, awareness increasing, running media campaigns can be effective on the issue of organ donation.

 Conclusion



Based on TPB, subjective norms and attitudes toward donation on signing a donor card have a positive effect on organ donation, whereas religiosity and bodily integrity were believed to negatively influence signing a donor card. Plus the main constructs of TPB which affect behavioral intention, background factors of the behavior should be considered as the behavior’s pre-factors, including knowledge, religion, social norms, culture, race, and gender. These factors should be considered in any related intervention. Removing barriers and facilitating the behavior, changing attitude, also subjective norms especially family can make interventions more effective.

The result supports public education and community campaigns promoting the necessity of sharing donation intentions with others.

 Limitations



This study may not be generalizable to all population groups.

Conflict of interest: None declared.

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