Vaccines and Immunity Theme, MRC Unit The Gambia at the London School of Hygiene and Tropical Medicine, Fajara, The Gambia.
Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom.
PLoS One. 2021 Jun 17;16(6):e0253423. doi: 10.1371/journal.pone.0253423. eCollection 2021.
The literature on the timeliness of childhood vaccination (i.e. vaccination at the earliest appropriate age) in low-and middle-income countries has important measurement and methodological issues that may limit their usefulness and cross comparison. We aim to conduct a comprehensive scoping review to map the existing literature with a key focus on how the literature on vaccination timeliness has evolved, how it has been defined or measured, and what determinants have been explored in the period spanning the last four decades. This scoping review protocol was developed based on the guidance for scoping reviews from the Joanna Briggs Institute. We will include English and French language peer-reviewed publications and grey literature on the timeliness of routine childhood vaccination in low-and middle-income countries published between January 1978 through to 2021. A three-step search strategy that involves an initial search of two databases to refine the keywords, a full search of all included electronic databases, and screening of references of previous studies for relevant articles missing from our full search will be employed. The search will be conducted in five electronic databases: MEDLINE, EMBASE, Global Health, CINAHL and Web of Science. Google search will also be conducted to identify relevant grey literature on vaccination timeliness. All retrieved titles from the search will be imported into Endnote X9.3.3 (Clarivate Analytics) and deduplicated. Two reviewers will screen the titles, abstracts and full texts of publications for eligibility using Rayyan-the web based application for screening articles for systematic reviews. Using a tailored data extraction template, we will extract relevant information from eligible studies. The study team will analyse the extracted data using descriptive statistical methods and thematic analysis. The results will be presented using tables, while charts and maps will be used to aid the visualisation of the key findings and themes. The proposed review will generate evidence on key methodological gaps in the literature on timeliness of childhood vaccination. Such evidence would shape the direction of future research, and assist immunisation programme managers and country-level stakeholders to address the needs of their national immunisation system.
儿童疫苗接种及时性的文献（即最早适当年龄的接种）在中低收入国家存在重要的测量和方法学问题，这些问题可能限制了它们的有用性和跨国家比较。我们旨在进行全面的范围综述，以绘制现有文献图，重点关注疫苗接种及时性文献的演变方式、如何定义或衡量及时性，以及在过去四十年期间探索了哪些决定因素。本范围综述方案是根据 Joanna Briggs 研究所的范围综述指南制定的。我们将纳入 1978 年 1 月至 2021 年期间发表的关于中低收入国家常规儿童疫苗接种及时性的英文和法文同行评议出版物和灰色文献。将采用三步搜索策略，包括初步搜索两个数据库以精炼关键词、全面搜索所有纳入的电子数据库，以及筛选以前研究的参考文献，以查找我们全面搜索中遗漏的相关文章。搜索将在五个电子数据库中进行：MEDLINE、EMBASE、全球健康、CINAHL 和 Web of Science。还将在 Google 搜索中搜索关于疫苗接种及时性的相关灰色文献。从搜索中检索到的所有标题都将导入到 Endnote X9.3.3（Clarivate Analytics）并去重。两名审查员将使用基于网络的 Rayyan 筛选文章进行系统综述，筛选出版物的标题、摘要和全文，以确定其是否符合纳入标准。使用定制的数据提取模板，我们将从合格研究中提取相关信息。研究团队将使用描述性统计方法和主题分析对提取的数据进行分析。结果将用表格呈现，图表和地图将用于辅助可视化关键发现和主题。拟议的综述将生成关于儿童疫苗接种及时性文献中关键方法学差距的证据。这些证据将为未来的研究指明方向，并帮助免疫规划管理人员和国家一级的利益攸关方满足其国家免疫体系的需求。
