Granerod J, White J M, Andrews N, Crowcroft N S
Immunisation Department, Health Protection Agency Centre for Infections, 61 Colindale Avenue, London NW9 5EQ, UK.
Arch Dis Child. 2006 Oct;91(10):805-7. doi: 10.1136/adc.2005.088625. Epub 2006 Feb 16.
To evaluate the impact of reorganisation of the health service and a change in the definition used to collect immunisation coverage statistics on vaccine coverage data in England.
Denominator data from the Cover Of Vaccination Evaluated Rapidly (COVER) programme, the national programme for the collection of immunisation coverage statistics, were compared to the Office for National Statistics (ONS) population data; the impact of any discrepancies between the two data sources on vaccine coverage was assessed.
ONS populations were generally larger than COVER populations. This was particularly true for 2002, the year Primary Care Trusts (PCTs) came into existence, suggesting that some children are being missed by the COVER programme. On average, in 1998-2001 around 10,000 children per year (approximately 2%) were lost to the COVER population estimates compared to data from ONS. This increased to around 20,000-40,000 (approximately 3-8%) children in 2002, but decreased again in 2003 to 2000-8000 (approximately 1%) children. Assuming all the "lost" COVER children were vaccinated, vaccine coverage appeared very similar to that seen in the COVER programme for all antigens. However, assuming all the "lost" children were unvaccinated, coverage would be substantially lower for all antigens (range 2.7-3.5%).
This analysis provides a quantitative example of how changes such as restructuring of the health service directly impact on public health surveillance. Such changes have potential risks for information and may affect important data used to inform public health policy.
评估卫生服务重组以及用于收集免疫接种覆盖率统计数据的定义变化对英格兰疫苗接种覆盖率数据的影响。
将免疫接种评估快速覆盖（COVER）计划（收集免疫接种覆盖率统计数据的国家计划）的分母数据与国家统计局（ONS）的人口数据进行比较；评估两个数据源之间的任何差异对疫苗接种覆盖率的影响。
ONS的人口通常比COVER的人口多。2002年初级保健信托基金（PCT）成立的那一年尤其如此，这表明COVER计划遗漏了一些儿童。平均而言，与ONS的数据相比，1998 - 2001年每年约有10,000名儿童（约2%）未被纳入COVER人口估计数。2002年这一数字增加到约20,000 - 40,000名儿童（约3 - 8%），但在2003年又降至2000 - 8000名儿童（约1%）。假设所有“遗漏”的COVER儿童都接种了疫苗，所有抗原的疫苗接种覆盖率与COVER计划中的情况非常相似。然而，假设所有“遗漏”的儿童都未接种疫苗，所有抗原的覆盖率将大幅降低（范围为2.7 - 3.5%）。
该分析提供了一个定量示例，说明卫生服务重组等变化如何直接影响公共卫生监测。此类变化存在信息方面的潜在风险，并可能影响用于为公共卫生政策提供依据的重要数据。
