Cross-cultural adaptation and validation of an Urdu version of the Vaccine Attitudes Examination (VAX-U) scale

Abstract

Background Martin and Petrie developed the Vaccine Attitudes Examination (VAX) scale with an aim to document general vaccination attitudes. Vaccine acceptance plays an important role in curbing COVID-19 infections. Thus, it was important to assess vaccination attitudes of Pakistani people towards novel COVID-19 vaccines. The VAX scale was not available in Urdu language for Pakistani population. Aim The study aimed to carry out cross-cultural adaptation and validation of an Urdu version of the Vaccine Attitude Examination (VAX) scale in a selected population sample from Pakistan. Methods A cross sectional study was conducted in September 2021 in an outpatient department of a healthcare facility in Karachi, Pakistan. Adult visitors, eligible for COVID-19 vaccine and spoke Urdu as first language were invited. Convenient sampling was used, and sample size was based on an item response ratio of 1:20. An Urdu version of the VAX scale was developed. The reliability was assessed using Cronbach's alpha (α) and intraclass correlation coefficient (ICC). The model fitness was evaluated using confirmatory factor analysis (CFA) and fit indices namely goodness of fit index (GFI), adjusted goodness of fit index (AGFI), Tucker Lewis index (TLI), comparative fit index (CFI), and root mean square error of approximation (RMSEA). A structural equation model (SEM) was also developed. IBM SPSS and AMOS were used to analyse the data. The study had ethical clearance. Results A total of 211 responses were analysed. The reliability (Cronbach's α) was 0.821. The ICC was 0.831 (95% CI: 0.795-0.863). CFA using a 4-factor model revealed the following values for fit indices; GFI = 0.944, AGFI = 0.909, TLI = 0.953, CFI = 0.966, and RMSEA = 0.051. All values reported were in the acceptable range. Conclusion The VAX Urdu version is a reliable and valid instrument for use in an Urdu speaking population and will enable clinicians to assess the public's attitude towards general vaccination including COVID-19 vaccination. Clinicians can use the VAX-U to document a person's vaccine hesitancy and tailor their counselling to address the issues in vaccine uptake.