Gaëlle Lièvre’s research while affiliated with Institut Pasteur and other places

Background The capacity of the 7C model’s psychological antecedents, which include confidence in vaccines, complacency, convenience, calculation, collective responsibility, confidence in the wider system, and social conformism, to explain variance in COVID-19 vaccine intentions and behaviours has been documented. However, it remains unclear whether the attitudes represented by the 7C psychological antecedents are specific to vaccination or if they are, in fact, an expression of underlying personality traits. Methods From February to June 2022, French adults completed self-administered questionnaires assessing COVID-19 vaccination history, the 7C antecedents, and personality traits (“ComCor” and “Cognitiv” studies). Vaccination behaviours were studied through three outcomes: at-least-one-dose vaccination status by 2022 (N = 49,019), up-to-date vaccination status (N = 46,566), and uptake speed of first dose (N = 25,998). Personality traits were evaluated using the French version of the Big Five Inventory (BFI-Fr). Multivariable logistic regressions and Cox models predicting vaccine behaviours were run with the 7C antecedents, both with and without personality traits. Results Among the 49,019 participants, 95.0% reported receipt of at least one dose and 89.8% were up to date with recommendations. All 7C antecedents were significantly associated with the outcomes. The inclusion of personality traits did not substantially alter the effect estimates of the association between the 7C antecedents and vaccination behaviours, with differences between effect sizes of models with and without personality traits being < 5%. Conclusions Our results suggest that the 7C psychological antecedents of vaccination are not the mere expression of personality and that their impact on vaccine behaviours is independent of personality traits. As such, the 7C antecedents may be modifiable by appropriate information and vaccine promotion. Trial registration The “ComCor” study received ethical approval by the Comité de Protection des Personnes Sud Ouest et Outre Mer 1 on 21/09/2020. The addition of the “Cognitiv” questionnaire received ethical approval by the Comité de Protection des Personnes Sud Ouest et Outre Mer 1 on 01/02/2022. The data protection authority Commission Nationale de l’Informatique et des Libertés (CNIL) authorised the processing of data on 21/10/2020. The study is registered with ClinicalTrials.gov under the identifier NCT04607941.

Background Widely documented psychological antecedents of vaccination are confidence in vaccines, complacency, convenience, calculation, collective responsibility (5C model) with the recent addition of confidence in the wider system and social conformism. While the capacity of these seven antecedents (7C) to explain variance in COVID-19 vaccine intentions has been previously documented, we study whether these factors also are associated with vaccine behaviours, beyond intentions. Methods From February to June 2022, we recruited a sample of adults in France, including persons with notified recent SARS-CoV-2 infection, along with relatives and randomly selected non-infected persons. Participants completed self-administered questionnaires assessing COVID-19 vaccination history and the 7C antecedents. We defined vaccination behaviours as three outcomes: at-least-one-dose vaccine status by 2022 (N = 49,019), up-to-date vaccination status (N = 46,566), and uptake speed of first dose (N = 25,998). We conducted multivariable logistic regressions and Cox models. Results Among the 49,019 participants, 95.0% reported receipt of at least one dose and 89.8% were up to date with recommendations. All 7C antecedents were significantly associated with the outcomes, although effects were weaker for up-to-date vaccination status and uptake speed. The strongest effects (most vs. least vaccine-favourable attitude level, at-least-one-dose vaccination status) were observed for collective responsibility (OR: 14.44; 95%CI: 10.72–19.45), calculation (OR: 10.29; 95%CI: 7.53–14.05), and confidence in the wider system (OR: 8.94; 95%CI: 6.51–12.27). Conclusion This study demonstrates that the 7C not only explain vaccine intention, but also vaccine behaviours, and underpins the importance of developing vaccine promotion strategies considering the 7C antecedents.