Development, validity, and reliability of the Japanese version of the 7C of vaccination readiness scale.

BACKGROUND: The 7C of the vaccination readiness scale measures the 7 psychological components that structure people's vaccination readiness. We aimed to develop the Japanese version of this scale (7C scale Japanese version) and to assess its validity and reliability. METHODS: The full and short versions of 7C scale Japanese were developed based on translation guidelines provided by the ISPOR Task Force. An Internet survey, including 709 participants, was performed to assess the scale's validity and reliability within a confirmatory factor analysis (CFA) framework (men: 38.8%, age range: 20-92 years). Invariance analysis using multiple-group CFA was conducted to test cross-cultural validity between participants in this study and those in the 7C original version study. McDonald's omega and intraclass correlation coefficient were calculated to evaluate internal consistency and test-retest reliability, respectively. To clarify the criterion validity, regression analysis, with previous COVID-19 vaccination status as the dependent variable, was performed to calculate pseudo R2. RESULTS: The 7C scale Japanese version exhibited good content validity, structural validity, configural invariance, and criterion validity. The results showed good internal consistency, and test-retest reliability, except for the "calculation" component. CONCLUSIONS: 7C scale Japanese version exhibited acceptable reliability and validity; however, "calculation" may be a less reliable subscale.

Measuring parents' readiness to vaccinate themselves and their children against COVID-19.

To reach high vaccination rates against COVID-19, children and adolescents should be also vaccinated. To improve childhood vaccination rates and vaccination readiness, parents need to be addressed since they decide about the vaccination of their children. We adapted the 7C of vaccination readiness scale to measure parents' readiness to vaccinate their children and evaluated the scale in a long and a short version in two studies. The study was first evaluated with a sample of N = 244 parents from the German COVID-19 Snapshot Monitoring (COSMO) and validated with N = 464 parents from the Danish COSMO. The childhood 7C scale showed acceptable to good psychometric properties in both samples and explained more than 80% of the variance in vaccination intentions. Additionally, differences in parents' readiness to vaccinate their children against COVID-19 were strongly determined by their readiness to vaccinate themselves, explaining 64% of the variance. Vaccination readiness and intentions for children changed as a function of the children's age explaining 93% of differences between parents in their vaccination intentions for their children. Finally, we found differences in correlations of components with self- versus childhood vaccination, as well as between the children's age groups in the prediction of vaccination intentions. Thus, parents need to be targeted in specifically tailored ways, based on the age of their child, to reach high vaccination rates in children. The scale is publicly available in several languages (www.vaccination-readiness.com).