VARIATIONS IN PM-10 CONCENTRATIONS WITHIN 2 METROPOLITAN-AREAS AND THEIR IMPLICATIONS FOR HEALTH-EFFECTS ANALYSES
VARIATIONS IN PM-10 CONCENTRATIONS WITHIN 2 METROPOLITAN-AREAS AND THEIR IMPLICATIONS FOR HEALTH-EFFECTS ANALYSES
复制标题
DOI：
10.3109/08958379509014477
复制
发表时间：
1995-07-01
影响因子：
2.1
通讯作者：
THURSTON, GD
中科院分区：
文献类型：
--
作者：
ITO, K;KINNEY, PL;THURSTON, GD
在1985年和1990年之间在两个主要的大都市地区，库克县，IL，和洛杉矶县，CA，在多个站点的PM-10水平的时间变化的特点，和死亡率PM-10协会的敏感性进行了检查，以选择替代网站。在这两个城市中，多个站点之间PM-10水平的相关性随着距离的增加而降低。虽然在多个地点平均PM-10浓度通常会提高PM-10死亡率关联的重要性，但库克县的PM-10死亡率关联最高的是单个地点。在库克县，平均6个PM-10地点的死亡率关联程度，表示为每100 μ g/m3 PM-10的“相对风险”，与具有类似模型规格的其他PM-10研究报告的结果相似（RR = 1.06，95%CI 1.01-1.10）。然而，个别PM-10站点的回归系数的显著性差异很大，其比值范围为-0.62至3.30）。此外，在库克县的一个站点的每日数据的每6天的子样本显示了广泛的回归系数的显着性（t比范围-0.17至3.44）。这六个地点之间的显著性差异可能部分是由于它们的样本量小（n约为300），这引起了人们对“短"研究期内健康影响分析的统计能力可能受损的担忧（
Temporal variations of PM-10 levels at multiple sites between 1985 and 1990 in two major metropolitan areas, Cook County, IL, and Los Angeles County, CA, were characterized, and sensitivity of mortality-PM-10 associations to the choice of alternate sites was examined. In both cities, the correlation of PM-10 levels among multiple sites decreased as their distance increased. While averaging PM-10 concentrations over multiple sites generally improved the significance of PM-10-mortality associations, the highest PM-10-mortality association in Cook County was found for an individual site. In Cook County, the magnitude of the mortality association for the average of 6 PM-10 sites, as expressed as ''relative risk'' per 100 mu g/m(3) PM-10, was similar (RR = 1.06, 95% CI 1.01-1.10) to those reported in other PM-10 studies with similar model specifications. However, the significance of regression coefficients for individual PM-10 sites varied considerably it ratios range -0.62 to 3.30). Furthermore, every-6-days subsamples of the daily data at a site in Cook County showed a wide range in the significance of regression coefficients (t ratios range -0.17 to 3.44). This variability of significance among the six sites may be partly due to their small sample sizes (n approximate to 300), which raises concern regarding the potential for compromised statistical power of health effects analyses in ''short'' study periods (