Favato Giampiero, Noikokyris Emmanouil, Vecchiato Riccardo
Institute of Leadership and Management in Health, Kingston University London, London, UK.
Kingston Business School, Kingston University London, Kingston Hill, Kingston-upon-Thames, KT2 7LB, London, UK.
Syst Rev. 2017 Jan 25;6(1):17. doi: 10.1186/s13643-017-0409-7.
Sexually transmitted infection with high-risk, oncogenic strains of human papillomavirus (HPV) still induces a relevant burden of diseases on both men and women. Although vaccines appear to be highly efficacious in preventing the infection of the most common high-risk strains (HPV 6, 11, 16, 18), important questions regarding the appropriate target population for prophylactic vaccination are still debated. Models in the extant literature seem to converge on the cost-effectiveness of high coverage (>80%) of a single cohort of 12-year-old girls. This vaccination strategy should provide an adequate level of indirect protection (herd immunity) to the unvaccinated boys. This argument presupposes the ecological validity of the cost-effectiveness models; the implicit condition that the characteristics of the individuals and the sexual behaviours observed in the models is generalisable to the natural behaviours of the population. The primary aim of this review is to test the ecological validity of the cost-effectiveness models of universal HPV vaccination available in the literature. The ecological validity of each model will be defined by the number of representative characteristics and behaviours taken into consideration.
Nine bibliographic databases will be searched: MEDLINE (via PubMed); Scopus; Science Direct; EMBASE via OVID SP, Web of Science, DARE, NHIR EED and HTA (via NHIR CRD); and CINHAL Plus. An additional search for grey literature will be conducted on Google Scholar and Open Grey. A search strategy will be developed for each of the databases. Data will be extracted following a pre-determined spreadsheet and then clustered and prioritised: the main outcomes will report the inputs to the demographic and epidemiological model, while additional outcomes will refer to basic inputs to the cost-effectiveness valuation. Each study included in the review will be scored by the number of representative characteristics and behaviours taken into consideration (yes or no) on both dimensions. Individual study's scores will be plotted in a 2 by 2 matrix: studies included in the upper right quadrant will be defined as ecologically valid, since which both individuals' characteristics and their sexual behaviours are representative.
The proposed systematic review will be the first to assess the ecological validity of cost-effectiveness studies. In the context of sexually transmitted diseases, when this condition is violated, an error in predicting the protective impact of herd immunity would occur. Hence, a vaccination policy informed on ecologically invalid models would potentially expose boys to a residual risk of contracting HPV-induced malignancies.
PROSPERO CRD42016034145.
高危致癌型人乳头瘤病毒（HPV）的性传播感染依然给男性和女性带来了相当大的疾病负担。尽管疫苗在预防最常见的高危型毒株（HPV 6、11、16、18）感染方面似乎非常有效，但关于预防性疫苗接种的合适目标人群仍存在重要争议。现有文献中的模型似乎都认为，对单一队列的12岁女孩进行高覆盖率（>80%）接种具有成本效益。这种疫苗接种策略应为未接种疫苗的男孩提供足够水平的间接保护（群体免疫）。这一论点预先假定了成本效益模型的生态有效性；即模型中观察到的个体特征和性行为特征能够推广到人群的自然行为这一隐含条件。本综述的主要目的是检验文献中通用HPV疫苗接种成本效益模型的生态有效性。每个模型的生态有效性将由所考虑的代表性特征和行为的数量来定义。
将检索九个文献数据库：MEDLINE（通过PubMed）；Scopus；Science Direct；通过OVID SP检索的EMBASE、Web of Science、DARE、NHIR EED和HTA（通过NHIR CRD）；以及CINHAL Plus。还将在谷歌学术和Open Grey上额外搜索灰色文献。将为每个数据库制定检索策略。数据将按照预先确定的电子表格进行提取，然后进行聚类和优先级排序：主要结果将报告人口统计学和流行病学模型的输入，而其他结果将涉及成本效益评估的基本输入。纳入综述的每项研究将根据在两个维度上所考虑的代表性特征和行为的数量（是或否）进行评分。个体研究得分将绘制在一个2×2矩阵中：右上角象限中的研究将被定义为生态有效，因为其个体特征及其性行为均具有代表性。
拟议的系统综述将首次评估成本效益研究的生态有效性。在性传播疾病的背景下，如果违反了这一条件，就会在预测群体免疫的保护作用时出现错误。因此，基于生态无效模型的疫苗接种政策可能会使男孩面临感染HPV诱发恶性肿瘤的残余风险。
PROSPERO CRD42016034145。
