Objective  To construct a decision-making process model on vaccination of coronavirus disease 2019 (COVID-19) vaccine and to explore reasons of unwilling to have the vaccination from public perspective for providing theoretical evidences to COVID-19 vaccination promotion.

  Methods  Using a self-designed open-ended questionnaire on COVID-19 vaccine hesitancy, we conducted a survey among 347 students in a medical university during March 27 – 29, 2021 – one week after the students′ applying voluntarily for COVID-19 vaccination. Word frequency and text node analysis on collected information were carried out and word cloud maps were generated with NVivo 12 software. A theoretical framework for vaccination decision-making process model was constructed based on grounded theory.

  Results  Valid information were collected from all the participants. In the respondents′ responses in writing about reasons for having COVID-19 vaccination, the words with high frequency included COVID-19, prevention, vaccination, and free of charge; while, safety, vaccine, effectiveness and adverse reaction were among the high frequency words in the writings on COVID-19 vaccine hesitancy. In the respondents′ writing texts, 3 parent nodes and 9 child nodes were identified. According to theoretical models of bio-psycho-social medicine, protective behavior decision, and vaccine hesitation/vaccination willingness and considering the results of previous studies, the public motivation for COVID-19 vaccination could be summarized into three aspects with nine causal factors as following: objective biological determination (factors relevant to virology/pharmacology and physiology/pathology), subjective psychological determination (personal risk and benefit judgment, vaccine safety, vaccine efficacy, and perceived social responsibility), and social determination (service accessibility, information accessibility). The three determinant aspects with nine relevant factors ought to be concerned in the construction of theoretical framework of vaccination decision-making process model for the public.

  Conclusion  A vaccination decision-making process model for the public was preliminarily constructed for the promotion of COVID-19 vaccination willingness and behavior in Chinese population.