National Centre for Immunisation Research and Surveillance, and Discipline of Paediatrics and Child Health, The University of Sydney, Australia.
Vaccine. 2013 Jan 30;31(6):967-72. doi: 10.1016/j.vaccine.2012.11.099. Epub 2012 Dec 13.
Hospital discharge records and laboratory data have shown a substantial early impact from the rotavirus vaccination program that commenced in 2007 in Australia. However, these assessments are affected by the validity and reliability of hospital discharge coding and stool testing to measure the true incidence of hospitalised disease. The aim of this study was to assess the validity of these data sources for disease estimation, both before and after, vaccine introduction.
All hospitalisations at a major paediatric centre in children aged <5 years from 2000 to 2009 containing acute gastroenteritis (AGE) ICD 10 AM diagnosis codes were linked to hospital laboratory stool testing data. The validity of the rotavirus-specific diagnosis code (A08.0) and the incidence of hospitalisations attributable to rotavirus by both direct estimation and with adjustments for non-testing and miscoding were calculated for pre- and post-vaccination periods.
A laboratory record of stool testing was available for 36% of all AGE hospitalisations (n=4948) the rotavirus code had high specificity (98.4%; 95% CI, 97.5-99.1%) and positive predictive value (96.8%; 94.8-98.3%), and modest sensitivity (61.6%; 58-65.1%). Of all rotavirus test positive hospitalisations only a third had a rotavirus code. The estimated annual average number of rotavirus hospitalisations, following adjustment for non-testing and miscoding was 5- and 6-fold higher than identified, respectively, from testing and coding alone. Direct and adjusted estimates yielded similar percentage reductions in annual average rotavirus hospitalisations of over 65%.
Due to the limited use of stool testing and poor sensitivity of the rotavirus-specific diagnosis code routine hospital discharge and laboratory data substantially underestimate the true incidence of rotavirus hospitalisations and absolute vaccine impact. However, this data can still be used to monitor vaccine impact as the effects of miscoding and under-testing appear to be comparable between pre and post vaccination periods.
在澳大利亚，2007 年开始实施轮状病毒疫苗接种计划，医院出院记录和实验室数据显示该计划对疾病产生了重大的早期影响。然而，这些评估受到医院出院编码和粪便检测的有效性和可靠性的影响，因为这些数据用于衡量住院疾病的真实发病率。本研究的目的是评估在疫苗接种前后这些数据来源对疾病估计的有效性。
将 2000 年至 2009 年期间，一家主要儿科中心 5 岁以下儿童的所有急性肠胃炎（AGE）ICD 10 AM 诊断代码编码的住院治疗与医院实验室粪便检测数据相关联。在疫苗接种前后，分别计算轮状病毒特异性诊断代码（A08.0）的有效性和轮状病毒引起的住院病例归因发病率，包括直接估计和非检测及错误编码调整。
所有 AGE 住院治疗（n=4948）中有 36%的住院治疗可获得实验室粪便检测记录，轮状病毒编码具有很高的特异性（98.4%；95%CI，97.5-99.1%）和阳性预测值（96.8%；94.8-98.3%），敏感性适中（61.6%；58-65.1%）。所有轮状病毒检测阳性的住院治疗中，只有三分之一的患者有轮状病毒编码。在调整非检测和错误编码后，每年平均轮状病毒住院治疗人数分别比单独检测和编码估计的人数高出 5 倍和 6 倍。直接和调整后的估计结果表明，每年平均轮状病毒住院治疗人数减少了 65%以上。
由于粪便检测的使用有限，以及轮状病毒特异性诊断代码的敏感性较差，常规医院出院和实验室数据大大低估了轮状病毒住院治疗的真实发病率和绝对疫苗效果。然而，由于在疫苗接种前后，错误编码和检测不足的影响似乎相当，因此这些数据仍可用于监测疫苗效果。
