Vaccine hesitancy (VH) is considered a top-10 global health threat. The concept of VH has been described and applied inconsistently. This systematic review aims to clarify VH by analysing how it is operationalized. We searched PubMed, Embase and PsycINFO databases on 14 January 2022. We selected 422 studies containing operationalizations of VH for inclusion. One limitation is that studies of lower quality were not excluded. Our qualitative analysis reveals that VH is conceptualized as involving (1) cognitions or affect, (2) behaviour and (3) decision making. A wide variety of methods have been used to measure VH. Our findings indicate the varied and confusing use of the term VH, leading to an impracticable concept. We propose that VH should be defined as a state of indecisiveness regarding a vaccination decision.

疫苗犹豫 (VH) 被认为是全球十大健康威胁。 VH 概念的描述和应用不一致。本系统综述旨在通过分析 VH 的运作方式来阐明 VH。我们于 2022 年 1 月 14 日检索了 PubMed、Embase 和 PsycINFO 数据库。我们选择了 422 项包含 VH 操作化的研究纳入。一个限制是不排除质量较低的研究。我们的定性分析表明，VH 被概念化为涉及 (1) 认知或情感、(2) 行为和 (3) 决策。已使用多种方法来测量 VH。我们的研究结果表明 VH 一词的使用多种多样且令人困惑，从而导致了一个不切实际的概念。我们建议 VH 应定义为对于疫苗接种决定犹豫不决的状态。