The influence of admission procedures on trust in vaccines

We investigate whether the duration and type of vaccine admission process affects trust in the vaccine, and intentions to get vaccinated. Therefore, we plan to run a vignette experiment in a nationally representative survey in Germany. We present respondents different hypothetical vignetts that describe a new anti-Covid vaccine. Across vignettes, we vary (i) the duration of the admission process, and (ii) the type of admission. After presenting the vignettes, we elicit respondents’ trust in the vaccine, intentions to get vaccinated.

Subjects will conduct the experiment via an online platform.
Subjects will be randomly assigned to one of four experimental groups, and each subject takes decisions in two consecutive stages.

Stage 1: Hypothetical vignettes — [Wording:]
Treatment 1: Please imagine the following hypothetical situation:
Suppose that a new vaccine against COVID-19 has been developed and tested in Germany. The vaccine is based on a novel mRNA technology and has an efficacy of 90%. One vaccine dose is needed for vaccine protection.
The vaccine received marketing authorization from the European Medicines Agency (EMA) and the European Commission after a new so-called "emergency use authorization" of 5 days (from the date of application by the manufacturer). The approval is valid for all countries of the European Union.
An emergency approval is characterized by the fact that the benefit in the sense of efficacy does not have to be proven. Compared to a "standard approval procedure," the presumed benefit has to be compared to the known risks.

Treatment 2: Please imagine the following hypothetical situation:
Suppose that a new vaccine against COVID-19 has been developed and tested in Germany. The vaccine is based on a novel mRNA technology and has an efficacy of 90%. One vaccine dose is needed for vaccine protection.
The vaccine received marketing authorization from the European Medicines Agency (EMA) and the European Commission after a new so-called "emergency use authorization" of 20 days (from the date of application by the manufacturer). The approval is valid for all countries of the European Union.
An emergency approval is characterized by the fact that the benefit in the sense of efficacy does not have to be proven. Compared to a "standard approval procedure," the presumed benefit has to be compared to the known risks.

Treatment 3: Please imagine the following hypothetical situation:
Suppose that a new vaccine against COVID-19 has been developed and tested in Germany. The vaccine is based on a novel mRNA technology and has an efficacy of 90%. One vaccine dose is needed for vaccine protection.
The vaccine received marketing authorization from the European Medicines Agency (EMA) and the European Commission after a new so-called "fast-track authorization" of 20 days (from the date of application by the manufacturer). The approval is valid for all countries of the European Union.
A fast-track authorization is characterized by the fact that review processes are already carried out in parallel with the development of the vaccine (i.e., even before the manufacturer submits an application). Compared to a "standard approval procedure", there are no quality differences in the testing of the efficacy and safety of the vaccine.

Treatment 4: Please imagine the following hypothetical situation:
Suppose that a new vaccine against COVID-19 has been developed and tested in Germany. The vaccine is based on a novel mRNA technology and has an efficacy of 90%. One vaccine dose is needed for vaccine protection.
The vaccine received marketing authorization from the European Medicines Agency (EMA) and the European Commission after a new so-called "fast-track authorization" of 150 days (from the date of application by the manufacturer). The approval is valid for all countries of the European Union.
A fast-track authorization is characterized by the fact that review processes are already carried out in parallel with the development of the vaccine (i.e., even before the manufacturer submits an application). Compared to a "standard approval procedure", there are no quality differences in the testing of the efficacy and safety of the vaccine.

Stage 2: Questions about trust and incentive to vaccinate — [Question wording:]
[Q01 – Q04]: To what extent do you agree with the following statement in relation to the situation just described?
[Q01] "All in all, I trust the vaccine."
[Q02] "I trust that the vaccine is safe."
[Q03] "I trust that the vaccine is effective."
[Q04] "I would get vaccinated with the vaccine."

[Answer categories:]
5-point scale: 1: “I fully agree”, 2: “I rather agree”, 3: “I rather disagree”,
4: “I do not agree at all”, 5: “Neither”

[Q05] Now it's a question of how much the vaccine described above would be worth to you: What is the most you would be willing to pay to be vaccinated with the vaccine tomorrow?
(State the most you would pay out of your own pocket if the vaccine were available for you to purchase. Please indicate "0" euros if you do not want to be vaccinated with this vaccine. If you have already been vaccinated, please put yourself in the situation as if you have not yet been vaccinated.)
____ Euro
[Answer categories:]
Open answer – number.

[Q06] And what is the most you would be willing to pay to have a person of your choice (not you) vaccinated with the vaccine tomorrow?
(State the maximum amount you would pay out of your own pocket if the vaccine were available for you to purchase. Please indicate "0" euro if you do not want a person of your choice to be vaccinated with this vaccine.)
____ Euro
[Answer categories:]
Open answer – number.

[Treatment Variation:]
As explained above, the randomized vignettes differ from one another as follows:
[Treatment 1] — “emergency use authorization" — 5 days
[Treatment 2] — “emergency use authorization" — 20 days
[Treatment 3] — “fast-track authorization" — 20 days
[Treatment 4] — “fast-track authorization" — 150 days

2021-03-26

2021-04-30

Trust in the vaccine (3 outcomes), intention to get vaccinated (1 outcome), and willingness to pay for the vaccine (2 outcomes). In our main analysis, we will create summary indices of these outcomes and estimate treatment effects on these indices. We will also investigate treatment effects on the individual outcomes.

We conduct the experiment in a sample of 2,000 adults aged between 18 and 69 years. The survey is conducted in cooperation with a survey institute. The recruitment and polling is managed by the survey institute, who collects the data via an online platform. That is, our participants answer the survey questions autonomously on their own digital devices. Randomization is carried out by the survey institute at the individual level, using a computer.
Our experiment is structured as follows:
Respondents of the survey will be randomly assigned (between subject) to
Treatment I (p=0.25), Treatment II (p=0.25), Treatment III (p=0.25), or Treatment IV (p=0.25).

Treatment I:
Stage 1: Presentation of vignette (version 1)
Stage 2: Questions: trust in the vaccine + intentions to get the vaccine.
Treatment II:
Stage 1: Presentation of vignette (version 2)
Stage 2: Questions: trust in the vaccine + intentions to get the vaccine.
Treatment III:
Stage 1: Presentation of vignette (version 3)
Stage 2: Questions: trust in the vaccine + intentions to get the vaccine.
Treatment IV:
Stage 1: Presentation of vignette (version 4)
Stage 2: Questions: trust in the vaccine + intentions to get the vaccine.

Randomization is carried out by the survey company respondi, using a computer.

at the individual level

No

2,000 individuals (adults aged between 18 and 69 years)

2,000 individuals — 500 per treatment

2,000 individuals — 500 per treatment