How Motives Related to Benefits for Oneself and Others Would Affect COVID-19 Vaccination in a Hong Kong Chinese General Adult Population?

Outcome expectancies involving self-directed and others-directed domains are potential determinants of completed or scheduled first-dose COVID-19 vaccination (CSFCV). This study investigated factors of CSFCV, including (a) self-directed motives [personal positive outcome expectancies (POE) and personal negative outcome expectancy (NOE)], and (b) others-directed motives (societal POE and the personality trait of prosociality). It also investigated the mediations of personal POE between societal POE and CSFCV, and moderations of prosociality between personal POE/personal NOE/societal POE and CSFCV. A cross-sectional population-based telephone survey interviewed 500 people aged 18–75 in Hong Kong in May 2021. The prevalence of CSFCV was 21.0%. Significant factors of CSFCV included personal POE (i.e., physical/practical/emotional/interpersonal benefit), personal NOE, and societal POE. The association between societal POE and CSFCV was fully mediated by the overall scale and some domains of personal POE. Furthermore, the association between physical benefit and CSFCV was stronger at lower levels of prosociality; prosociality showed a stronger effect on CSFCV at lower levels of physical benefit. The results suggest that self-directed motives might be more important than others-directed motives in affecting CSFCV. The findings require confirmations from longitudinal studies and cross-country comparisons.