Nocebo-Effekte nach Impfungen: Der Einfluss von Einstellungen und Framing-Effekten auf die Impfbereitschaft und Impfreaktionen
Loading...
Files
Date
relationships.isAuthorOf
Publisher
Philipps-Universität Marburg
item.page.supervisor-of-thesis
Abstract
Vaccination is a cost-effective protective measure against infectious diseases. However, despite the preventive benefits of vaccination for the individual and for society as a whole, target vaccination rates are often not achieved. Vaccine hesitancy, which means the delayed acceptance or refusal of vaccination despite available vaccination offers, is a much-studied phenomenon and has already been declared one of ten global health threats by the World Health Organization in 2019. Adverse treatment effects attributable to nocebo phenomena can be demonstrated in clinical practice in the context of various interventions. However, despite their significant influence on quality of life and treatment adherence, these effects in connection with vaccinations have received little consideration so far. Findings about the influence of nocebo mechanisms in the vaccination process can serve to better understand vaccine hesitancy and to derive suitable measures to counteract it.
First, to test the assumption of the presence of nocebo phenomena associated with vaccination, two meta-analyses summarizing adverse events in placebo arms of 31 randomized controlled trials of influenza vaccines and 12 SARS-CoV-2 vaccination trials were conducted. After an alleged influenza vaccination, which was exclusively a pharmacologically inactive sham vaccination, 25.3% reported at least one systemic adverse event such as headache or fatigue. In the placebo groups of the COVID-19 studies, 35.2% of the participants reported systemic reactogenicity symptoms after a first sham vaccination and 31.8% after a second application. There was evidence of nocebo effects associated with vaccination.
Based on the known influence of attitudes and expectations on the occurrence of nocebo effects, a third study was conducted, translating the English version of the Vaccination Attitude Examination (VAX) Scale by Martin and Petrie (2017) into German. The translated questionnaire was validated in two pre-/pandemic samples with 297 and 260 participants. The psychometric parameters of the translated scale indicated a valid and reliable instrument for assessing general anti-vaccination attitudes in German-speaking countries. In addition, there were significant correlations between average VAX scale values and willingness to be vaccinated.
In a fourth online study, the treatment expectations of an imagined vaccination were addressed using an expectation-optimizing communication strategy derived from placebo/nocebo research. In a 2x2 study design, 652 participants received information on influenza vaccination or vaccination against COVID-19, formulated according to standard or adapted using framing strategies and supplemented with information on nocebo effects. The communication strategy showed an effect on the cost-benefit expectations of influenza vaccination. Furthermore, the groups of both vaccines expected fewer unpleasant vaccination reactions if they had been informed in an expectation-optimizing manner. There was no influence on the willingness to be vaccinated, but moderation analyzes indicated that people who were more critical of vaccinations were even less willing to be vaccinated after the adapted information was provided.
The results of the present dissertation show that nocebo phenomena are associated with vaccinations or reactogenicity symptoms and can be influenced using communication strategies that optimize expectations. These strategies should not be used without restrictions due to the different effects on people who are particularly critical of vaccination.
Review
Metadata
Contributors
Supervisor:
Dates
Created: 2023Issued: 2025-03-13Updated: 2025-03-13
Faculty
Fachbereich Psychologie
Publisher
Philipps-Universität Marburg
Language
ger
Data types
DoctoralThesis
Keywords
communicationvaccinationadverse events following immunizationquestionnaire validationframing effectvaccination readinessMeta-Analysevaccine reactogenicityAEFIvaccination attitudesFragebogenvalidierungvaccine hesitancyimmunizationmeta-analysis
DFG-subjects
ImpfmüdigkeitKommunikationFraming-EffektImpfungenImpfbereitschaftImpfeinstellungenImpfreaktionen
DDC-Numbers
150
show more
Bender, Friederike (M.Sc.) (0000-0002-2915-7509): Nocebo-Effekte nach Impfungen: Der Einfluss von Einstellungen und Framing-Effekten auf die Impfbereitschaft und Impfreaktionen. : Philipps-Universität Marburg 2025-03-13. DOI: https://doi.org/10.17192/z2024.0051.