Faculty of Geo-Information Science and Earth Observation (ITC), University of Twente, Enschede, Netherlands.
Sci Rep. 2019 Sep 13;9(1):13217. doi: 10.1038/s41598-019-49549-4.
In 2012, nearly 644,000 people died from diarrhea in sub-Saharan Africa. This is a significant obstacle towards the achievement of the Sustainable Development Goal 3 of ensuring a healthy life and promoting the wellbeing at all ages. To enhance evidence-based site-specific intervention and mitigation strategies, especially in resource-poor countries, we focused on developing differential time trend models for diarrhea. We modeled the logarithm of the unknown risk for each district as a linear function of time with spatially varying effects. We induced correlation between the random intercepts and slopes either by linear functions or bivariate conditional autoregressive (BiCAR) priors. In comparison, models which included correlation between the varying intercepts and slopes outperformed those without. The convolution model with the BiCAR correlation prior was more competitive than the others. The inclusion of correlation between the intercepts and slopes provided an epidemiological value regarding the response of diarrhea infection dynamics to environmental factors in the past and present. We found diarrhea risk to increase by 23% yearly, a rate far exceeding Ghana's population growth rate of 2.3%. The varying time trends widely varied and clustered, with the majority of districts with at least 80% chance of their rates exceeding the previous years. These findings can be useful for active site-specific evidence-based planning and interventions for diarrhea.
2012 年，撒哈拉以南非洲地区有近 64.4 万人死于腹泻。这是实现可持续发展目标 3（确保健康的生活并促进各年龄段人群的福祉）的重大障碍。为了加强基于证据的特定地点干预和缓解策略，特别是在资源匮乏的国家，我们专注于开发腹泻的差异化时间趋势模型。我们将每个地区的未知风险的对数建模为时间的线性函数，并具有空间变化的影响。我们通过线性函数或双变量条件自回归（BiCAR）先验来诱导随机截距和斜率之间的相关性。相比之下，包含变截距和斜率之间相关性的模型表现优于不包含的模型。具有 BiCAR 相关性先验的卷积模型比其他模型更具竞争力。截距和斜率之间相关性的纳入提供了有关腹泻感染动态对过去和现在环境因素的反应的流行病学价值。我们发现腹泻风险每年增加 23%，这一增长率远远超过加纳 2.3%的人口增长率。变化的时间趋势差异很大且呈聚类分布，大多数地区的发病率至少有 80%的可能性超过前几年。这些发现可用于针对腹泻的主动、基于特定地点的循证规划和干预。
