Characteristics of survey participants
Between September 2016 and July 2020 several emails were sent via professional and private mailing lists and postings in social media groups were placed. Therefore, it is unknown to us, how many persons received an invitation for this questionnaire. 1223 people started the questionnaire, 164 only clicked on the link of the questionnaire and 7 started to answer the questions but did not submit any answers, therefore 1052 questionnaires were available for analysis. The mean age of respondents was 44 (44;45), 396 (37.6%) were male, 653 (62.1%) were female and 3 (0.3%) preferred not to tell. Male respondents were significantly older than female (46 (44;49) versus (42 (41;44) years, p < 0.0001). The majority (890; 84.6%) were Christian, 108 (10.3%) were atheists. 531 (50.5%) of the respondents considered themselves as religious, 510 (48.5%) said that they are not religious and 11 (1%) did not answer this question. The majority (693; 65.9%) reported a university degree as highest education, followed by apprenticeship (202; 19.2%) and high school education (140; 13.3%). By far the most respondents were from Austria (932; 88.6%), a few were from Germany (38; 3.6%), Italy (14; 1.3%) and Switzerland (13; 1.2%) and the remaining participants were from 24 countries with no more than 6 respondents from the same country. More women than men (53.6% versus 46.3%, p = 0.025) reported that they are religious, more male respondents came from other countries than Austria (15.9% versus 7.0%, p < 0.0001), and more men had a university education (76.6% versus 60% of the women, p < 0.0001). Religion influenced the rate of respondents who considered themselves as religious (Christian: 57.2%, other religions 30% and atheists 13%, p < 0.0001), whereas being religious or not was not associated with education and nationality. Table 1 summarizes the characteristics of the participants
Table 1
Description of the study population
|
|
N
|
Percentage (from total participants n = 1052)
|
Gender
|
Female
|
653
|
62.1
|
|
Male
|
396
|
37.6
|
|
No answer
|
3
|
0.3
|
Religion
|
Christian
|
890
|
84.6
|
|
Atheist
|
108
|
10.3
|
|
Buddhism
|
10
|
1.0
|
|
Islam
|
2
|
0.2
|
|
Other
|
30
|
2.9
|
|
No answer
|
12
|
1.1
|
Religious
|
Yes
|
531
|
50.5
|
|
No
|
510
|
48.5
|
|
No answer
|
11
|
1
|
Country
|
Austria
|
932
|
88.6
|
|
Germany
|
38
|
3.6
|
|
Italy
|
14
|
1.3
|
|
Switzerland
|
13
|
1.2
|
|
Other*
|
43
|
4.1
|
|
No answer
|
12
|
1.1
|
Education
|
University
|
693
|
65.9
|
|
High school
|
140
|
13.3
|
|
Apprenticeship
|
202
|
19.2
|
|
Compulsory education
|
14
|
1.3
|
|
No answer
|
3
|
0.3
|
*Algeria, Argentina, Australia, Azerbaijan, Bahamas, Bosnia and Herzegovina, Bulgaria, Burkina Faso, Canada, Croatia, Czech Republic, Greece, Hungary, India, Kazakhstan, Netherlands, Poland, Romania, Serbia, Slovakia, Slovenia, South Korea, Spain, Thailand
|
The majority of the respondents were health care professionals (73.1%), and from those the majority (86%) reported to work with critically ill patients. From those who reported to work with critically ill patients, 65.5% reported that they are professionally involved in treatment decisions in critically ill patients. (Fig. 1) 21.6% reported that they already were critically ill or in a life-threatening situation themselves and of those, 65.6% were personally involved in treatment decisions. 77.6% reported that a closely related person has been critically ill or in a life-threatening situation. Of those, 58.6% stated that they were personally involved in treatment decisions. Male respondents were more likely to work with critically ill than women (92.3% versus 86.3%, p = 0.017) and to be professionally involved in treatment decisions (83.5% versus 55.6%, p < 0.0001). Interestingly, more people who reported that they had been critically ill themselves, also considered themselves to be religious (60.3% versus 48.3% who were not critically ill, p = 0.002). A similar association was found for those who reported that one of their relatives was critically ill (53.0% versus 44.2% who had no relatives who were critically ill, p = 0.002). Level of education was significantly associated with working as a health care professional (university 81.9%, high school 44.9%, apprenticeship 68.9%, compulsory education 50%, p < 0.0001), working with critically ill (university 91.0%, high school 76.3%, apprenticeship 85.6%, compulsory education 57.3%, p < 0.0001), and being professionally involved in treatment decisions (university 82.5%, high school 20%, apprenticeship 12.6%, compulsory education 25%, p < 0.0001), the numbers of participants with compulsory education are very low and it is unlikely that people with compulsory education only are professionally involved in treatment decisions of critically ill patients; therefore results for this group are questionable. For multivariate analysis education was grouped into university and other (combining high school, apprenticeship and compulsory education).
Participant´s answers regarding necessary survival chances and acceptable risks of intensive care treatments
Participants were asked to imagine that they are in the hospital with a life-threatening disease and to give their opinion for which survival chance they would undergo a risky and uncomfortable treatment on a slide scale between 0 and 100%. Next, they were asked to choose for a close friend or relative. And finally, all participants were asked to imagine that they are in a situation for which a risky and uncomfortable treatment will ensure survival, but there is a risk of severe disability after the treatment. They were asked, which risk of severe disability with the need for long-term care they would consider acceptable. Those, who stated that they were health care workers and were professionally involved in treatment decisions of critically ill patients, were also asked to imagine that they are treating a critically ill patient who is unconscious and to decide which survival chance they would consider necessary to begin a risky and uncomfortable treatment on this patient and which risk of severe disability with the need for long-term care they would consider acceptable.
Responses of all five questions covered the complete span from 0-100%. The distribution shows a triphasic pattern for all answers in the density plots (Fig. 2A-E) The answers regarding the necessary survival chances for the respondents themselves and for their relatives showed the highest density of answers in the middle tercile, the answers regarding necessary patient survival and acceptable risk for disability for themselves and patients showed the highest peak in the lowest tercile. (Table 2)
Table 2
Distribution of answers regarding necessary survival chances and acceptable risks of critical care treatments (grouped into terciles; low 0–33%, medium 34–66%, high 67–100%)
|
|
N
|
percentage
|
self survival
|
low
|
298
|
29,0%
|
|
medium
|
383
|
37,2%
|
|
high
|
348
|
33,8%
|
relative survival
|
low
|
332
|
32,1%
|
|
medium
|
390
|
37,7%
|
|
high
|
312
|
30,2%
|
patient survival
|
low
|
222
|
52,5%
|
|
medium
|
128
|
30,3%
|
|
high
|
73
|
17,3%
|
patient risk
|
low
|
251
|
61,8%
|
|
medium
|
99
|
24,4%
|
|
high
|
56
|
13,8%
|
self risk
|
low
|
676
|
73,0%
|
|
medium
|
195
|
21,1%
|
|
high
|
55
|
5,9%
|
Table 3
Multivariate multinomial logistic regression model for necessary survival chances to accept a risky and uncomfortable procedure during critical illness. The lowest tercile (0–33%) of necessary survival chances was chosen as comparator. Independent predictors are printed in bold.
Variable
|
Comparisons
|
Wald
|
adjusted
odds ratio
|
95% confidence interval
|
adjusted p-value
|
Medium necessary survival chance
|
Constant
|
|
3.469
|
|
|
|
0.063
|
Gender
|
female compared to male
|
10.991
|
1.714
|
1.247
|
2.358
|
0.001
|
Education
|
lower education compared to university education
|
8.622
|
1.728
|
1.199
|
2.489
|
0.003
|
Health care professional
|
no compared to yes
|
0.492
|
1.145
|
0.784
|
1.671
|
0.483
|
High necessary survival chances
|
Constant
|
|
15.817
|
|
|
|
< 0.001
|
Gender
|
female compared to male
|
17.167
|
2.024
|
1.450
|
2.826
|
< 0.001
|
Education
|
lower education compared to university education
|
17.321
|
2.185
|
1.512
|
3.158
|
< 0.001
|
Health care professional
|
no compared to yes
|
1.207
|
1.241
|
0.844
|
1.823
|
0.272
|
Influence of demographic factors on the answers regarding necessary survival chances and acceptable risks of critical care treatments
Male respondents consider a lower chance of survival necessary for themselves (p < 0.0001), for their relatives (p < 0.0001) and for patients (p < 0.039) to undertake a risky and uncomfortable treatment compared to female respondents. (Fig. 3A-C) While religion did not influence the answers, being religious resulted in considering a lower chance of survival necessary to begin a risky and uncomfortable treatment for relatives (p = 0.034) but being religious did not influence any other answer. (Fig. 3D) Nationality was grouped in “Austria” and “other” for this analysis, however, sample size for other nations was still small (n = 108), therefore the results for nationality need to be interpreted with caution. Having a nationality other than Austrian resulted in the acceptance of a higher risk of severe disability with the need for long-term care for themselves (p = 0.014) and respondents considered a lower chance of survival necessary for patients to start a risky and uncomfortable treatment (p = 0.009, only n = 48 answers in this group) (Fig. 3E and F). Respondents with university education (p < 0.0001 compared to apprenticeship, p = 0.016 compared to high school) or high school education (p = 0.008 compared to apprenticeship) would consider a lower chance of survival necessary to begin a risky and uncomfortable treatment for themselves. A comparable result was obtained for the necessary survival chance of relatives. (Fig. 3G and H)
Influence of professional or personal exposure to critical care on the answers regarding necessary survival chances and acceptable risks of critical care treatments
Being a health care professional but not being involved in treating critically ill patients influenced the answers. Health care professionals would accept a lower chance of survival themselves and for relatives necessary to begin a risky and uncomfortable treatment (both p = 0.023). (Fig. 4A and B) When analyzing the results separately for female and male respondents, female health care professionals did not respond differently to non-health care professionals, whereas male health care professionals would accept a lower chance of survival for themselves and for relatives compared to male non-medical respondents. Those, who stated that they are professionally involved in treatment decisions of critically ill patients, would consider a lower chance of survival for themselves (p < 0.0001) and for relatives (p < 0.0001) necessary to begin a risky and uncomfortable treatment and accept a higher risk of severe disability with the need for long-term care for themselves (p = 0.002) (Fig. 4C-E). No gender specific patterns were observed when comparing people who are professionally involved in treatment decisions with those who are not involved. Neither having experienced a critical illness personally nor with a close relative or friend influenced the answers on the necessary survival chance and risk of disability. Also, personal involvement in treatment decisions either when self-affected or for close relatives or friends did not influence the answers on the necessary survival chance and risk of disability.
Multivariate analysis of factors influencing the answers regarding necessary survival chances and acceptable risks of critical care treatments
To understand, which demographic factors influence the necessary survival chances or acceptable disability risks, multinomial logistic regression was used to test the effects of the variables found to influence answers by Mann-Whitney tests (gender, education, religiosity, being a health care professional and being involved in treatment decisions). The choices of the survival chance necessary to accept a risky or uncomfortable procedure for the respondents themselves were influenced by gender (p < 0.001), education (p < 0.001) and making treatment decisions for patients (p < 0.001). In a multivariate model including gender, education and being a health care professional, only gender and education independently influenced the opinion of the participants. (see Table 1)
In a separate model, only health care professionals were analysed to test the influence of being involved in treatment decision and gender on the choice of necessary survival chances of the respondents themselves. Education was excluded from the model because of its strong associations with treatment decision experience. Both, gender (p = 0.001) and being professionally involved in treatment decisions (p < 0.001) were independently influencing the choice of necessary survival chances. (supplementary Table 1)
Since gender, education, and being a health care professional were not independent of each other, subgroup analysis was done to validate the results of the regression model. The choice of necessary survival chances to accept a risky or uncomfortable procedure of university educated health care professionals involved in treatment decisions (n = 406) was only influenced by gender (p = 0.002) while gender did not play a role for university educated participants who were not health care professionals (p = 0.212). For healthcare professionals who were not involved in treatment decisions (n = 220), the main explanatory variable was religiosity (p = 0.020). Participants who claimed not to be religious were more likely to choose medium or high necessary survival chances to accept a risky or uncomfortable procedure compared to religious participants (OR = 2.167, 95%CI: 1.001–4.728, p = 0.05; and OR = 2.919, 95%CI: 1.355–6.289, p = 0.006, for medium and high necessary survival chances, respectively).
Similar patterns were found for the necessary survival chances to accept a risky or uncomfortable procedure for a close relative. Gender (p < 0.001), education (p < 0.001), health care profession (p = 0.035) and being professionally involved in treatment decisions (p < 0.001) significantly influenced the answers. Analogous to the necessary survival changes to accept a procedure for oneself, female participants, non-university educated participants, participants with a health care-unrelated profession as well as health care professionals who were not professionally involved in treatment decisions for critically ill patients, were more likely to require medium or high survival chances to accept a treatment for their relatives, compared to male participants, university educated participants, participants with health care professions and health care professionals involved in treatment decisions, respectively. The respective odds ratios are given in supplementary table 2.
For health care professionals with university level education involved in treatment decisions, the driving force was gender (p < 0.001); female participants were more likely to choose medium or high necessary survival chances compared to male participants (OR = 2.522, 95%CI: 1.598–3.980, p < 0.001, and OR = 1.752, 95%CI: 1.046–2.934, p = 0.033, for medium and high survival chances, respectively). For university educated participants who were not health care professionals as well as for health care professionals who were not professionally involved in treatment decisions for critically ill patients, no prominent influencing factor could be identified.
The multinomial logistic regression model to predict the acceptable disability risks to save one’s life, identified having a health care profession as the only significant influencing factor (p = 0.045). Participants who do not have a health care profession were more likely to accept high risks of disability to save their lives compared to health care professionals (OR = 1.869, 95%CI: 1.036–3.370, 0.038, for medium and high risk, respectively). No other factor showed significant influence on this decision, neither in the whole study population nor when health care professionals and non-health care professionals were examined separately.
When health care professionals were asked to choose the necessary survival rate of patients to start a risky or uncomfortable treatment, the answers were mainly influence by gender (p = 0.007) and education (p = 0.020). Female participants were more likely to require medium necessary survival chances compared to male participants and non-university educated participants were more likely to require high necessary survival chances compared to university educated participants. This pattern was validated in a multivariate model (supplementary table 3)
Since gender was such a prominent influence on most of the categories, we further analysed female and male participants separately. For male participants, a university education (p = 0.002), being a health care professional (p = 0.006) and being professionally involved in treatment decisions for critically ill patients (p = 0.002) were the most influential factors for the necessary survival chances for themselves to accept a risky or uncomfortable treatment. Thereby, being a health care professional was dependent on education and only education was identified as independent predictor by a multivariate model (including education and health care profession). Being professionally involved in treatment decisions and education were highly dependent on each other and could therefore not be fitted in one model. For female participants, education (p = 0.001), being professionally involved in treatment decisions (p = 0.004) and religiosity (p = 0.003) were the most influential factors in this decision. In a multivariate model including education and religiosity, both proved to be independent influencing factors. In a multivariate model including religiosity and being professionally involved in treatment decisions also both factors independently predict the necessary survival chances. All relevant odds ratios are listed in supplementary table 4, multivariate models in the subsequent tables 5–9.
For males, the necessary survival chances for a relative were influenced by education (p = 0.003), health care profession (p = 0.020), being professionally involved in treatment decision for a patient (p = 0.001) and having been involved in treatment decisions for a critically ill relative before (p = 0.020). Interestingly, having been involved in treatment decisions for a critically ill relative was not relevant as influencing factors in any other decision or group. In a multivariate model, education and having been involved in treatment decisions (but not being a health care professional) proofed to be independent predictors for the necessary survival chances. Answers of female participants were influenced by education (p = 0.011) and religiosity (p = 0.003), which both showed significant but oppositional influence on the necessary survival chances for relatives. There was no difference in education between religious and non-religious women (p = 0.221).
The answers of male participants to the question of the acceptable risk for disability could not be predicted by any of our demographic factors. For females, a marginal influence of being a health care professional could be found (p = 0.040). Non-health care professional women were more likely to choose to accept higher risks over lower risks compared to female health care professionals (OR = 2.259, 95%CI: 1.058–4.824, p = 0.035). Neither for the necessary survival rate nor the acceptable disability risk for a patient, gender-specific influential factors could be identified.
Relation between answers regarding necessary survival chances and acceptable risks of critical care treatments
When comparing the answers regarding the necessary chance of survival for the respondents, for relatives and for patients to start a risky and uncomfortable treatment, respondents would start a risky and uncomfortable treatment for patients with lower survival chances than for themselves or relatives (p < 0.0001). Accordingly, the acceptable risk of severe disability was lower for the respondents themselves compared to the patients. (p < 0.0001) The necessary chance of survival for the respondents themselves, for relatives and for patients positively correlated with each other (r = 0.870, p < 0.0001; r = 0.657, p < 0.0001). Also, the acceptable risk of severe disability for oneself correlates with the result for patients (r = 0.452, p < 0.0001). A weak negative correlation between the necessary chances of survival for themselves and for relatives with the acceptable risk of severe disability was also observed (r=-0.127, p < 0.0001, p=-0.128, p < 0.0001) respectively). (Fig. 5)
A substantial proportion of respondents would consider either a lower (27.8%) or higher (18.2%) survival chance necessary to start a risky or uncomfortable treatment for their relatives as compared to themselves. 20.6% would consider a lower and only 9.8% a higher survival chance necessary for patients than for themselves for starting a risky or uncomfortable treatment. When asked for the acceptable risk of disability, 16.9% would accept a higher and 10.5% a lower risk of disability for patients than for themselves. Differing answers for the necessary survival for respondents themselves compared to relatives were not influenced by any of the demographic variables. Differing answers for the necessary survival of respondents themselves compared to patients was influenced by gender, 79.9% of female participants but only 67.7% of male participants gave a differing answer for patients compared to themselves. No influence of demographic variables on the difference between the acceptable risk of the respondents compared to the risk of patients was observed.