Risk stratification for prediction of spread and severity by Covid-19 in Brazilian federation units

Abstract Objectives: To perform risk stratification for dissemination and mortality by COVID-19 from Brazilian federal units (FU), based on characteristics identified as risk situations. Methods: Social, demographic and health indicators were selected and underwent principal components analysis. Then, it was possible to divide the FUs by cluster analysis. Based on the factor load of the components created, a final score for the UF was obtained and they were then stratified with regard to the risk of dissemination and mortality by COVID-19. Findings: Components created refer to assistance, health (including risk factors), demographic and social conditions. These components allowed for the final classification of the 27 FU, with a difference in order with regard to the potential for dissemination and mortality. Conclusions: We believe risk stratification may be a measure to support public health, defining areas with the greatest potential for damage and on that basis, allow for the creation of priority intervention strategies.

**摘要**
研究目的：基于已被识别为风险情境的特征，针对巴西联邦辖区（Federal Units, FU）开展新型冠状病毒肺炎（COVID-19）传播与死亡风险分层研究。
研究方法：选取社会、人口及健康指标开展主成分分析，随后通过聚类分析对各联邦辖区进行分组。基于所提取成分的因子载荷，计算得到各联邦辖区的最终得分，并据此对其新冠传播与死亡风险进行分层。
研究结果：所提取的成分涵盖医疗救助、健康（含风险因素）、人口与社会状况四大维度。借助上述成分可完成27个联邦辖区的最终分类，且各辖区在传播与死亡风险潜力上存在显著层级差异。
研究结论：本研究认为，风险分层可作为支撑公共卫生决策的有效手段，能够明确潜在损害风险最高的区域，并据此制定优先干预策略。