Ledogar Robert J, Fleming John, Andersson Neil
CIETinternational, 511 Avenue of the Americas #132, New York, NY, USA.
BMC Int Health Hum Rights. 2009 Oct 14;9 Suppl 1(Suppl 1):S6. doi: 10.1186/1472-698X-9-S1-S6.
In preparation for a cluster-randomized controlled trial of a community intervention to increase the demand for measles vaccination in Lasbela district of Pakistan, a balance sheet summarized published evidence on benefits and possible adverse effects of measles vaccination.
The balance sheet listed: 1) major health conditions associated with measles; 2) the risk among the unvaccinated who contract measles; 3) the risk among the vaccinated; 4) the risk difference between vaccinated and unvaccinated; and 5) the likely net gain from vaccination for each condition.
Two models revealed very different projections of net gain from measles vaccine. A Lasbela-specific combination of low period prevalence of measles among the unvaccinated, medium vaccination coverage and low vaccine efficacy rate, as revealed by the baseline survey, resulted in less-than-expected gains attributable to vaccination. Modelled on estimates where the vaccine had greater efficacy, the gains from vaccination would be more substantial.
Specific local conditions probably explain the low rates among the unvaccinated while the high vaccine failure rate is likely due to weaknesses in the vaccination delivery system. Community perception of these realities may have had some role in household decisions about whether to vaccinate, although the major discouraging factor was inadequate access. The balance sheet may be useful as a communication tool in other circumstances, applied to up-to-date local evidence.
为在巴基斯坦拉斯贝拉地区开展一项社区干预的整群随机对照试验做准备，该试验旨在提高麻疹疫苗接种需求，一份资产负债表总结了已发表的关于麻疹疫苗接种益处和可能不良反应的证据。
资产负债表列出了：1）与麻疹相关的主要健康状况；2）未接种疫苗而感染麻疹者的风险；3）接种疫苗者的风险；4）接种疫苗者与未接种疫苗者之间的风险差异；以及5）每种状况下接种疫苗可能带来的净收益。
两种模型显示麻疹疫苗净收益的预测差异很大。基线调查显示，拉斯贝拉地区未接种疫苗者中麻疹的低时期患病率、中等疫苗接种覆盖率和低疫苗有效率的特定组合，导致接种疫苗带来的收益低于预期。以疫苗效力更高的估计值为模型，接种疫苗的收益会更大。
特定的当地情况可能解释了未接种疫苗者比例较低的原因，而高疫苗失败率可能是由于疫苗接种实施系统存在缺陷。社区对这些现实情况的认知可能在家庭关于是否接种疫苗的决策中起到了一定作用，尽管主要的阻碍因素是接种机会不足。该资产负债表作为一种沟通工具，在其他情况下应用于最新的当地证据时可能会很有用。
