Table 1. Measures used in both studies with sample items, answer formats, and quality indicators (where applicable).
| Construct | Sample item and source | Answer format | Number of items, format, quality indicators | Used in Study 1 | Used in Study 2 |
|---|---|---|---|---|---|
| Attitude (affective, cognitive, and general attitude) | Affective: “According to my spontaneous gut instinct, organ donation is…” Cognitive: “Considering the advantages and disadvantages of organ donation, I think organ donation is…” General: “Now we want to know your personal evaluation of the topic organ donation. How do you evaluate organ donation in general?” [31] |
Affective and cognitive: Seven-point semantic differential scales, with “I don’t know” as an additional option (bad-good, unimportant-important, unsafe-safe) General: seven-point Likert scale (very negative/very positive) with “I don’t know” as an additional option |
Seven items; mean across seven items Cronbach’s α’s between .850 and .915 |
T1, T2, T3 | T1, T2, T3 |
| Knowledge | “A brain-dead person can awaken again.“ Based on [32–34] |
true, false, I don’t know | Seven items (all of which referred to topics mentioned during the treatment); sum score, transformed into POMP score | T2, T3 | T1, T2, T3 |
| Fears | “I fear that I’m not really dead after a brain death.” Based on [32–34] |
Seven-point Likert scales (strongly disagree/strongly agree) | Seven items (all of which referred to topics mentioned during the treatment); sum score, recoded, transformed into POMP score | T2, T3 | T1, T2, T3 |
| Behavioral intentions | “In the near future, I intend to”: (1) make a decision about organ donation (2) communicate the decision to my family or friends (3) sign an organ donation card [31] |
Seven-point Likert scales (extremely unlikely/extremely likely) with an extra answer option (already done) | Three items; mean across three items, Cronbach’s α’s between 0.903 and 0.932 | T1, T2, T3 | T1, T2, T3 |
| Previous behavior | Whether participants already: (1) made a decision (2) communicated their decision to others (3) noted their decision on an organ donation card |
Yes, no, I don’t know | Three items; Cronbach’s α = .897 (Study 1); α = .878 (Study 2) | T1 | T1 |
| Immediate behavior | Participants took the organ donation card available in the experiment with them | yes, no | T2 | T2 | |
| Follow-up behavior | Participants indicated whether, during the past four weeks, they had: (1) made a decision (2) communicated their decision to others (3) recorded their decision on an organ donation card |
Yes, no, I don’t know, already done | Three items; Cronbach’s α = .838 (Study 1); α = .855 (Study 2) | T3 | T3 |
| Perceived funniness overall, treatment | “How funny did you perceive the show in general?” “How funny did you perceive the organ donation stand-up?” (intervention group only) [16] | 10-point Likert scale (not at all funny/extremely funny) | Single items | T2 | |
| Perceived funniness treatment | Rating of how information about organ donation was presented | Seven-point semantic differentials (not funny-funny, not amusing-amusing, not humorous-humorous, not entertaining-entertaining) | Four items; mean across four items, Cronbach’s α = .949 | T2 | |
| Reactance | “I felt a resistance inside because of a strong perceived manipulation” [35] | Seven-point Likert scale (strongly disagree/strongly agree) | Three items; mean across three items, Cronbach’s α = .826 (Study 1); α = .825 (Study 2) | T2 | T2 |
| Counter-arguing | “I questioned some statements” [23] | Seven-point Likert scale (strongly disagree/strongly agree) | One item* | T2 | T2 |
| Issue involvement | “Organ donation is a personally relevant topic for me” [36] | Seven-point Likert scale (strongly disagree/strongly agree), with “I don’t know” as an extra option | Seven items; mean across seven items, Cronbach’s α = .879 | T1 |
All questionnaires containing all measures are provided at https://osf.io/vkn4s. POMP = percent of maximum possible score ([observed score-minimum score]/[maximum score-minimum score] x 100). An increase of 1 on a POMP scale corresponds to an increase of 1% on the original scale.
* As the two assessed items were not reliable, we chose the items with greater variance.