在疫情趨緩的後疫情時代下，人們是否還願意接種第四劑疫苗？本研究以展望理論為基礎，透過線上實驗調查法探討個體在已接種滿三劑 COVID-19 疫苗的情況下，利得與損失框架、個人主義與集體主義之文化觀點組成之訊息如何影響其對 COVID-19 第四劑疫苗的感知風險，進一步影響其對該疫苗的態度與接種行為意圖，又對該疫苗的感知障礙如何影響其態度與行為意圖間的關係。研究結果發現，訊息框架對於個體在該疫苗的感知風險上具有顯著效果，然而文化觀點卻無顯著影響，甚至兩者交互作用也無任何影響，而感知風險與態度呈顯著負相關，即當個體對於 COVID-19 疫苗感知風險越高，對該疫苗態度越負面，反之則越正面，而態度與行為意圖呈顯著正相關，不過感知障礙對於疫苗態度與接種疫苗行為意圖之關係並無顯著影響。 

 In the post-epidemic era, are people still willing to receive a fourth dose of the vaccine? Based on prospective theory, this study investigates how the message of gain and loss framework, individualism and collectivism cultural perspectives affects individuals' perceived risk of the fourth dose of COVID-19 vaccine, further influences their attitude and behavioral intention toward the vaccine through an online experimental survey. It was found that message framing had a significant effect on individuals' perceived risk of the vaccine, but cultural views did not have any significant effect, even when they interacted with each other, and perceived risk was significantly negatively related to attitude, while attitude was significantly positively related to behavioral intention. However, there was no significant effect of perceived barrier on the relationship between vaccine attitudes and behavioral intentions to receive the vaccine.