Examining age, period and cohort effects in attitude change to childhood vaccinations in a representative New Zealand survey: a multiyear cohort-sequential growth modelling study.

Abstract

Vaccinations are an important preventative measure in reducing the spread of infectious diseases worldwide. However, concerns of undervaccination during childhood have become increasingly common. The current study aims to investigate changes in attitudes towards childhood vaccinations prior to the COVID-19 pandemic using a national sample from New Zealand. Age-based, period-based, and cohort-based changes were assessed using cohort-sequential latent growth modelling in 11 overlapping birth cohorts, which spanned the ages of 23-79 years. Data were taken from the New Zealand Attitudes and Values Study where 58 654 adults completed at least one wave across a 7-year period (2013 and 2015-2019). The period-based and cohort-based models fit the data equally well (χ²(282)=8547.93, p<0.001, comparative fit index, CFI=0.894, root mean square error of approximation, (RMSEA)=0.074, standardised root mean square residual, SRMR=0.105; χ²(273)=8514.87, p<0.001, CFI=0.894, RMSEA=0.075, SRMR=0.105, respectively) suggesting societal factors contribute to childhood vaccination attitudes. Additionally, the findings suggest attitudes towards childhood vaccinations were becoming increasingly more positive in all birth cohorts (ps<0.001), with younger and older birth cohorts exhibiting even positive attitudes compared with middle-aged cohorts. Overall, both the cohort-based and period-based models reveal changes in vaccination attitudes suggesting that even prior to the COVID-19 pandemic, societal influences had an impact on attitudes towards childhood vaccination.