Background
Methods
Study eligibility criteria
Search strategy
Study selection and data extraction
Theoretical domain | Definition | Example applied to the field of euthanasia |
---|---|---|
1. Knowledge | An awareness of information related to a given behavior. | Knowing the criteria for being admissible for euthanasia in countries where it is legalized. |
2. Skills | An ability to perform a certain act. | Having the skills needed to perform voluntary euthanasia. |
3. Social/professional role and identity | How one perceives s/he should act according to his/her social and professional identity. | Perceiving euthanasia as compatible with a caregiver’s role. |
4. Beliefs about capabilities | A perceived capacity to adopt a given behavior. | Perceiving being able to perform voluntary euthanasia. |
5. Beliefs about consequences | Perceived anticipated consequences of adopting the behavior. | Anticipating that euthanasia will have positive consequences for the patient, such as relieving him/her of pain. |
6. Social influences | How one perceives others would react if s/he adopted a given behavior (i.e., approval or disapproval). | Perceiving that the patient’s family would approve if the physician euthanized his/her patient. |
7. Emotions | Feelings arising at the thought of adopting the behavior or following behavioral adoption. | Feeling guilty or being afraid at the thought of performing euthanasia. |
8. Moral norm* | How a given behavior is perceived according to one’s personal and moral values. | Perceiving euthanasia as compatible with one’s personal and moral values. |
9. Past behavior* | Past experience with a given behavior. | Having already performed euthanasia in the past. |
Data analyses
Results
Characteristics of the studies
Reference | Country | Outcome | Sample | Theory used | Response rate | Main results: |
---|---|---|---|---|---|---|
Positive association (+) | ||||||
Negative association (-) | ||||||
No association (0) | ||||||
Association unknown (+/-) | ||||||
Asch & DeKay [20] | United States | Behavior | 1 139 critical care nurses: | N/A | 73% | • Euthanasia and PAS are unethical (-) |
Age: 38.5 (8.7) | • Passive euthanasia is unethical (-) | |||||
5.1% male | • Working in cardiac care unit (-) | |||||
• Ever asked to engage in euthanasia (+) | ||||||
Back et al. [21] | United States | Behavior | 828 physicians (GPs and specialists): | N/A | 57% | Reasons for not providing euthanasia: |
Age: NR | • Physicians should never perform euthanasia | |||||
76.3% male | • The symptoms were potentially treatable | |||||
• The duration of the patient survival was expected to be > 6 months | ||||||
• The patient was depressed | ||||||
• The degree of patient suffering did not justify the request | ||||||
• Worried about legal consequences | ||||||
Davis et al. [22] | Australia, Canada, China, Finland, Israel, Sweden and United States | Behavior | 168 cancer care nurses: | N/A | N/A | • Patient wish |
Age range: 19-64 | • Severe suffering | |||||
% male: NR | • Terminally ill | |||||
• Family agree | ||||||
DeKeyser Ganz & Musgrave [23] | Israel | Behavior | 71 critical care nurses | N/A | N/A | Religiosity (-) |
Doukas et al. [24] | United States | Behavior and intention (willing) | 154 oncologists: | Belief-attitude-intention-behavior model of Fishbein | 61.6% | Behavior: |
Age: 49 | • University-based oncologists have administered (+) | |||||
83% male | Intention: | |||||
• University-based oncologists willing (+) | ||||||
• Religion (+/-) | ||||||
• Global attitude scale (+) | ||||||
• Philosophical scale (+) | ||||||
• Alternative attitude scale (+) | ||||||
Essinger [25] | United States | Intention (willingness) | 365 physicians (GPs and specialists): | N/A | 34% | • Deliberate administration of an overdose is never ethically justified |
Age: 48.7 | ||||||
84.7% male | • Euthanasia is inconsistent with the physician’s role to relieve pain and suffering (-) | |||||
• Religion (-) | ||||||
Folker et al. [26] | Denmark | Behavior | 314 physicians (21% GPs): | N/A | 64% | • Euthanasia is ethically acceptable |
Median age: 47 | • Euthanasia would make me feel uncomfortable | |||||
69% male | • Euthanasia is incompatible with my role as a physician | |||||
Inghelbrecht et al. [42] | Belgium (Flanders) | Intention (never prepared to administer lethal drugs) | 3321 nurses: | N/A | 62.5% | • Sex: women vs. men (+) |
77% older than 36 years | • Education: baccalaureate vs. diploma (-) | |||||
12.4% male | Master vs. diploma (-) | |||||
• Religion: Catholic vs. non-religious (+) | ||||||
Protestant vs. non-religious (+) | ||||||
Other religion vs. non-religious (+) | ||||||
• Work setting: home care vs. other (+) | ||||||
• Experiences with end-of-life decisions with 3 or more patients: yes vs. no (-) | ||||||
Kinsella & Verhoef [27] | Canada | Intention (willingness to practice euthanasia if it were legalized) | 1391 physicians (GPs and specialists): | N/A | 69% | • Sex (+) |
51% over the age of 40 years | • Religious affiliation and activity (+) | |||||
78% male | • Country of graduation (+) | |||||
Kohart [28] | United States | Behavior | 93 physicians (GPs and specialists): | N/A | 42.1% | • Relieve patient pain |
Age: 47 | • Patient’s desire to die | |||||
95.7% male | • Reallocate resources | |||||
• Relieve family concern | ||||||
Kuhse & Singer [29] | Australia | Behavior | 869 physicians (GPs and specialists): | N/A | 46% | • Euthanasia is not the doctor’s role |
Age range: < 30 to > 60 years | • Euthanasia was the right thing | |||||
78.5% male | • Respecting the patient’s wish | |||||
• It is right for a doctor to take active steps to bring about the death of a patient who has requested the doctor to do this | ||||||
Kuhse & Singer [30] | Australia | Behavior and intention (willingness) | 943 nurses: | N/A | 49% | Behavior: |
40% of respondents are in their 30s | • Euthanasia was the right thing | |||||
6% male | • Patient request | |||||
• Discussion with the family | ||||||
• Age | ||||||
• Religion | ||||||
Intention: | ||||||
• Age | ||||||
Kunene & Zungu [31] | South Africa | Behavior | 26 nurses: | N/A | 100% | 12% would administer a lethal dose of a drug in order to relieve suffering |
Age: NR | ||||||
8% male | ||||||
Maitra et al. [32] | Germany | Behavior and intention (willingness) | 233 GPs: | N/A | 48% | Behavior: |
Age: 51 | • Euthanasia was right in a moral sense | |||||
68% male | • Have received requests for euthanasia in the past (+) | |||||
Matzo [33] | United States | Behavior | 441 oncology nurses: | N/A | 74% | • Being married (0) |
Age: 42.0 (8.5) | • Being Jewish (0) | |||||
2% male | • Being Catholic (0) | |||||
• Income (0) | ||||||
• Race (0) | ||||||
• Age (0) | ||||||
• Religiosity (0) | ||||||
• Gender (0) | ||||||
• Highest degree (0) | ||||||
• Years since graduation (0) | ||||||
• Catholic religiosity (0) | ||||||
• Jewish religiosity (0) | ||||||
Meeusen et al. [43] | Belgium | Behavior | 205 GPs: | N/A | 91.9% | Reasons for granting a patient’s request: |
Age: NR | • Explicit & repeated request from patient | |||||
% male: NR | • Written request | |||||
Reasons for not granting a patient’s request: | ||||||
• Patient’s wish was not explicit & repeated | ||||||
• Patient’s suffering was not unbearable & persistent | ||||||
Meier et al. [34] | United States | Behavior | 379 physicians: | N/A | 63% | • Patient depressed at the time of request (-) |
Age: NR | • Patient in severe discomfort other than pain (+) | |||||
% male: NR | • Patient life expectancy < 1 month (+) | |||||
Obstein et al. [44] | The Netherlands | Behavior | 30 physicians: | N/A | 100% | • Positive experience with euthanasia |
Age: 49.3 | • No regrets after performing euthanasia | |||||
86.7% male | • Euthanasia is part of the role of a physician | |||||
• Euthanasia challenges personal morals | ||||||
Onwuteaka-Philipsen et al. [35] | Australia, Belgium, Denmark, Italy, The Netherlands, Sweden and Switzerland (before 2002) | Intention (willingness to perform end-of-life decisions) | 10 139 physicians (GPs and specialists): | N/A | 57.1% (overall) | • Request of patient with decisional capacity (+) |
Age: NR | • Advance directive of subcomatose patient (+) | |||||
% male: NR | • Request of family of patient with decisional capacity (-) | |||||
• Subcomatose patient, request of the family (+) | ||||||
• Subcomatose patient, own initiative of physician (+) | ||||||
• Life expectancy < 2 weeks (+) | ||||||
• Uncontrollable pain (+) | ||||||
• Religious, important for professional attitude (-) | ||||||
Onwuteaka-Philipsen et al. [45] | The Netherlands | Behavior | 6263 physicians (GPs and specialists): | N/A | 74% | Reasons for granting requests: |
Age: NR | • Wish of the patient | |||||
% male: NR | • No prospect of improvement | |||||
• No more options for treatment | ||||||
• Loss of dignity | ||||||
Oz [36] | Turkey | Behavior and intention (willingness) | 113 nurses: | N/A | Nurses: 39% Physicians: 31.8% | Nurses’ willingness to participate in legal euthanasia: |
Age: 78% between 20-30 | • Age (0) | |||||
0% male | Physicians’ willingness to participate in legal euthanasia: | |||||
84 physicians: | • Age: 20-30 vs. 31+ (+) | |||||
Age: 65.5% between 20-30 | Nurses’ reasons for wanting to make their patient’s death easy according to years of experience: | |||||
79.8% male | ||||||
• Pain and depression: 7+ years vs. 1-6 years (+) | ||||||
Physicians’ reasons for wanting to make their patient’s death easy according to years of experience: | ||||||
• Pain and depression: 1-6 years vs. 7+ years: (+) | ||||||
• Insufficient support: 7+ years vs. 1-6 years (+) | ||||||
Parker et al. [37] | Australia | Intention (willingness) | 1478 physicians (GPs and specialists): | N/A | 53% | Case 1: competent patient, life expectancy < 2 weeks: Anesthetists vs. palliative care specialists and oncologists (+) |
> 70% aged 40 or more | ||||||
Case 2: competent patient, life expectancy > 3 months: Anesthetists vs. palliative care specialists and oncologists (+) | ||||||
78% male | Case 3: incompetent patient, life expectancy < 2 weeks: Anesthetists vs. palliative care specialists and geriatricians (+) | |||||
Case 4: incompetent patient, life expectancy > 3 months: Anesthetists vs. palliative care specialists and geriatricians (+) | ||||||
Richardson [38] | United States | Behavior and intention (attitude) | 148 oncology nurses: | Kohlberg’s model of moral reasoning development | 74% | Behavior: |
Age: NR | • Religious attitude to euthanasia (-) | |||||
% male: NR | ||||||
Shapiro et al. [39] | United States | Intention (willingness) | 740 physicians (GPs and specialists): | N/A | 33% | Willingness to perform euthanasia: |
Age: 55.1% between 35-60 | • Family/general practice vs. other specialty or internal medicine (+) | |||||
84% male | • Christian fundamentalists vs other religions (Protestant, other) (-) | |||||
• Catholic vs. other religions (Protestant, other) (-) | ||||||
• Jewish vs. other religions (Protestant, other) (+) | ||||||
• Specified no religion vs. other religions (Protestant, other) (+) | ||||||
Willingness to perform euthanasia if it were legalized: | ||||||
• Family/general practice vs. other specialty or internal medicine (+) | ||||||
• Christian fundamentalist vs. other religions not in analysis (-) | ||||||
• Catholic vs. other religions not in this analysis (Protestant, other), and for uncertain outcome (Christian fundamentalist, Jewish) (-) | ||||||
• Jewish vs. other religions not in this analysis (Protestant, other) (+) | ||||||
• Specified no religion vs. other religions not in analysis (+) | ||||||
Smets et al. [46] | Belgium | Behavior | 914 physicians (GPs and specialists): | N/A | 34% | Religious affiliation/philosophy of life: |
Age: 45.1% between 51-65 | • Roman Catholic/strong practicing vs. not religious (-) | |||||
63.5% male | • Roman Catholic/moderately practicing vs. not religious (-) | |||||
• Roman Catholic/not practicing vs. not religious (-) | ||||||
• Religious, but no specific denomination vs. not religious (-) | ||||||
Specialty: | ||||||
• Specialist vs. general practitioner (+) | ||||||
Age (years): | ||||||
• 36-50 vs. < 35 (+) | ||||||
• 51-65 vs. < 35 (+) | ||||||
• > 65 vs. < 35 (+) | ||||||
Training in palliative care: yes vs. no (+) | ||||||
Number of terminal patients cared for in the last 12 months: • 1-9 vs. 0 (+) | ||||||
• ≥ 10 vs. 0 (+) | ||||||
Stevens & Hassan [40] | Australia | Behavior | 298 physicians: | N/A | 68% | Strong association between taking active steps and belief that such action was ‘right’ |
Age: NR | Reasons why they felt they had done the ‘right’ thing: | |||||
% male: NR | • This action had relieved pain, suffering and distress experienced by the patient | |||||
• The patient was near death | ||||||
• The situation was hopeless | ||||||
• The patient had no prospect of a meaningful or independent existence | ||||||
• Acted on orders | ||||||
Stevens & Hassan [41] | Australia | Behavior | 278 nurses: | N/A | 55% | Sex: male vs. female |
Age range: 20-59 | ||||||
6.5% male |
Reference | Response rate ≥ 60% | Verified whether respondents differed from non-respondents | Cases-to-predictors ratio > 15 for multivariate analyses |
---|---|---|---|
Asch & DeKay [20] | √ | √ | |
Back et al. [21] | √ | N/A | |
Davis et al. [22] | NR | NR | |
DeKeyser Ganz & Musgrave [23] | NR | N/A | |
Doukas et al. [24] | √ | N/A | |
Essinger [25] | N/A | ||
Folker et al. [26] | √ | √ | NR |
Inghelbrecht et al. [42] | √ | √ | N/A |
Kinsella & Verhoef [27] | √ | √ | N/A |
Kohart [28] | NR | ||
Kuhse & Singer [29] | NR | ||
Kuhse & Singer [30] | NR | ||
Kunene & Zungu [31] | √ | NR | |
Maitra et al. [32] | √ | ||
Matzo [33] | √ | √ | √ |
Meeusen et al. [43] | √ | NR | |
Meier et al. [34] | √ | √ | |
Obstein et al. [44] | √ | NR | |
Onwuteaka-Philipsen et al. [35] | √ | √ | |
Onwuteaka-Philipsen et al. [45] | √ | NR | |
Oz [36] | N/A | ||
Parker et al. [37] | N/A | ||
Richardson [38] | √ | N/A | |
Shapiro et al. [39] | √ | √ | |
Smets et al. [46] | √ | √ | |
Stevens & Hassan [40] | √ | NR | |
Stevens & Hassan [41] | N/A |
Characteristics of the participants
Most consistent variables associated with behavior and/or intention
Variables measured | Number of time | Ratio | |
---|---|---|---|
Assessed | Significant (p < 0.05) | (%) | |
Psychological variables* | |||
Past behavior | 3 | 3 | 100% |
Beliefs about consequences | 5 | 2 | 40.0% |
Social/professional role and identity | 6 | 2 | 33.3% |
Beliefs about capabilities | 3 | 1 | 33.3% |
Moral norm | 9 | 2 | 22.2% |
Emotions | 1 | 0 | N/A |
Total | 27 | 10 | 37.0% |
Socio-demographic variables** | |||
Medical specialty, unit and work setting | 9 | 6 | 66.6% |
Religion | 17 | 7 | 41.2% |
Number of terminal patients | 3 | 1 | 33.3% |
Gender | 10 | 3 | 30.0% |
Level of education | 4 | 1 | 25.0% |
Years of work experience | 5 | 1 | 20.0% |
Age | 12 | 2 | 16.6% |
Marital status | 3 | 0 | 0% |
Place of birth | 2 | 1 | N/A |
Had training in palliative care | 1 | 1 | N/A |
Income | 1 | 0 | N/A |
Ethnicity | 1 | 0 | N/A |
Total | 68 | 23 | 33.8% |
Patient variables** | |||
Patient depressed | 3 | 2 | 66.6% |
Patient’s life expectancy | 5 | 3 | 60.0% |
Patient’s symptoms and suffering | 10 | 4 | 40.0% |
Family agreement | 4 | 1 | 25.0% |
Patient’s wish | 7 | 1 | 14.3% |
Condition with no prospect of improvement | 4 | 0 | 0% |
Loss of dignity | 1 | 0 | N/A |
To reallocate resources | 1 | 0 | N/A |
Total | 35 | 11 | 31.4% |
Most consistent variables associated with behavior and/or intention according to health profession
Variables measured | Number of time | Ratio | |
---|---|---|---|
Assessed | Significant (p < 0.05) | (%) | |
Physicians (k = 17) | |||
Psychological variables
| |||
Beliefs about consequences | 5 | 2 | 40.0% |
Social/professional role and identity | 6 | 2 | 33.3% |
Moral norm | 7 | 1 | 14.3% |
Beliefs about capabilities | 2 | 1 | N/A |
Past behavior | 1 | 1 | N/A |
Emotions | 1 | 0 | N/A |
Total | 22 | 7 | 31.8% |
Socio-demographic variables
| |||
Medical specialty, unit and work setting | 6 | 4 | 66.6% |
Religion | 9 | 5 | 55.5% |
Number of terminal patients | 3 | 1 | 33.3% |
Age | 5 | 1 | 20.0% |
Gender | 6 | 1 | 16.6% |
Had training in palliative care | 1 | 1 | N/A |
Place of birth | 1 | 1 | N/A |
Years of experience | 1 | 0 | N/A |
Marital status | 1 | 0 | N/A |
Total | 33 | 14 | 42.4% |
Patient variables
| |||
Patient’s life expectancy | 4 | 3 | 75.0% |
Patient’s symptoms and suffering | 7 | 4 | 57.1% |
Patient’s wish | 5 | 1 | 20.0% |
Condition with no prospect of improvement | 4 | 0 | 0% |
Patient depressed | 2 | 2 | N/A |
Family agreement | 2 | 1 | N/A |
Loss of dignity | 1 | 0 | N/A |
To reallocate resources | 1 | 0 | N/A |
Total | 26 | 11 | 42.3% |
Nurses (k = 9) | |||
Psychological variables
| |||
Past behavior | 2 | 2 | N/A |
Moral norm | 2 | 1 | N/A |
Total | 4 | 3 | 75% |
Socio-demographic variables
| |||
Medical specialty, unit and work setting | 3 | 2 | 66.6% |
Gender | 4 | 2 | 50.0% |
Religion | 8 | 2 | 25.0% |
Level of education | 4 | 1 | 25.0% |
Age | 6 | 0 | 0% |
Years of experience | 3 | 0 | 0% |
Marital status | 2 | 0 | N/A |
Place of birth | 1 | 0 | N/A |
Income | 1 | 0 | N/A |
Ethnicity | 1 | 0 | N/A |
Total | 33 | 7 | 21.2% |
Patient variables
| |||
Patient’s symptoms and suffering | 2 | 0 | N/A |
Patient’s wish | 2 | 0 | N/A |
Family agreement | 2 | 0 | N/A |
Patient’s life expectancy | 1 | 0 | N/A |
Total | 7 | 0 | 0% |
Most consistent variables associated with behavior and/or intention according to legal status of euthanasia
Variables measured | Number of time | Ratio | |
---|---|---|---|
Assessed | Significant (p < 0.05) | (%) | |
Countries were euthanasia is not legal (k = 22) | |||
Psychological variables
| |||
Beliefs about consequences | 3 | 2 | 66.6% |
Social/professional role and identity | 5 | 2 | 40.0% |
Beliefs about capabilities | 3 | 1 | 33.3% |
Moral norm | 8 | 2 | 25.0% |
Past behavior | 2 | 2 | N/A |
Emotions | 1 | 0 | N/A |
Total | 22 | 9 | 40.9% |
Socio-demographic variables
| |||
Medical specialty, unit and work setting | 7 | 4 | 57.1% |
Religion | 15 | 5 | 33.3% |
Years of experience | 4 | 1 | 25.0% |
Gender | 9 | 2 | 22.2% |
Age | 10 | 1 | 10.0% |
Level of education | 3 | 0 | 0% |
Marital status | 3 | 0 | 0% |
Place of birth | 2 | 1 | N/A |
Number of terminal patients | 2 | 0 | N/A |
Income | 1 | 0 | N/A |
Ethnicity | 1 | 0 | N/A |
Total | 57 | 14 | 24.6% |
Patient variables
| |||
Patient depressed | 3 | 2 | 66.6% |
Patient’s life expectancy | 5 | 3 | 60.0% |
Patient’s symptoms and suffering | 9 | 4 | 44.4% |
Family agreement | 4 | 1 | 25.0% |
Patient’s wish | 5 | 1 | 20.0% |
Condition with no prospect of improvement | 2 | 0 | N/A |
To reallocate resources | 1 | 0 | N/A |
Total | 29 | 11 | 37.9% |
Countries where euthanasia is legal (k = 5) | |||
Psychological variables
| |||
Beliefs about consequences | 2 | 0 | N/A |
Past behavior | 1 | 1 | N/A |
Social/professional role and identity | 1 | 0 | N/A |
Moral norm | 1 | 0 | N/A |
Total | 5 | 1 | 20.0% |
Socio-demographic variables
| |||
Medical specialty, unit and work setting | 2 | 2 | N/A |
Religion | 2 | 2 | N/A |
Age | 2 | 1 | N/A |
Gender | 1 | 1 | N/A |
Had training in palliative care | 1 | 1 | N/A |
Number of terminal patients | 1 | 1 | N/A |
Level of education | 1 | 1 | N/A |
Total | 10 | 9 | 90.0% |
Patient variables
| |||
Patient’s wish | 2 | 0 | N/A |
Condition with no prospect of improvement | 2 | 0 | N/A |
Patient’s symptoms and suffering | 1 | 0 | N/A |
Loss of dignity | 1 | 0 | N/A |
Total | 6 | 0 | 0% |