Department of Epidemiology, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina 27514 , USA.
Environ Health Perspect. 2010 May;118(5):673-8. doi: 10.1289/ehp.0901158. Epub 2010 Jan 14.
Studies examining the health effects of particulate matter <or= 2.5 microm in aerodynamic diameter (PM2.5) commonly use ambient PM2.5 concentrations measured at distal monitoring sites as proxies for personal exposure and assume spatial homogeneity of ambient PM2.5. An alternative proxy-the residential outdoor PM2.5 concentration measured adjacent to participant homes-has few advantages under this assumption.
We systematically reviewed the correlation between residential outdoor PM2.5 and personal PM2.5 (-rj) as a means of comparing the magnitude and sources of measurement error associated with their use as exposure surrogates.
We searched seven electronic reference databases for studies of the within-participant residential outdoor-personal PM2.5 correlation.
The search identified 567 candidate studies, nine of which were abstracted in duplicate, that were published between 1996 and 2008. They represented 329 nonsmoking participants 6-93 years of age in eight U.S. cities, among whom -rj was estimated (median, 0.53; range, 0.25-0.79) based on a median of seven residential outdoor-personal PM2.5 pairs per participant. We found modest evidence of publication bias (symmetric funnel plot; pBegg = 0.4; pEgger = 0.2); however, we identified evidence of heterogeneity (Cochran's Q-test p = 0.05). Of the 20 characteristics examined, earlier study midpoints, eastern longitudes, older mean age, higher outdoor temperatures, and lower personal-residential outdoor PM2.5 differences were associated with increased within-participant residential outdoor-personal PM2.5 correlations.
These findings were similar to those from a contemporaneous meta-analysis that examined ambient-personal PM2.5 correlations (rj = median, 0.54; range, 0.09-0.83). Collectively, the meta-analyses suggest that residential outdoor-personal and ambient-personal PM2.5 correlations merit greater consideration when evaluating the potential for bias in studies of PM2.5-mediated health effects.
研究表明,在大气动力学直径(PM2.5)<2.5 微米的颗粒物对健康的影响,常使用远程监测站点测量的环境 PM2.5 浓度作为个人暴露的替代物,并假设环境 PM2.5 是空间均匀的。而另一种替代物,即毗邻参与者居所测量的住宅外 PM2.5 浓度,在这种假设下几乎没有优势。
我们系统地回顾了住宅外 PM2.5 与个人 PM2.5 (-rj)之间的相关性,旨在比较使用这两种替代物作为暴露代理时,其测量误差的大小和来源。
我们在七个电子参考数据库中搜索了关于参与者内在的住宅外个人 PM2.5 相关性的研究。
搜索共确定了 567 项候选研究,其中 9 项研究进行了重复摘要,这些研究发表于 1996 年至 2008 年期间,代表了美国八个城市的 329 名不吸烟参与者,年龄在 6 至 93 岁之间。基于每位参与者的中位数为 7 对住宅外个人 PM2.5 配对,估计了 -rj(中位数为 0.53;范围为 0.25-0.79)。我们发现存在适度的发表偏倚证据(对称漏斗图;pBegg = 0.4;pEgger = 0.2);然而,我们发现存在异质性证据(Cochran's Q 检验 p = 0.05)。在检查的 20 个特征中,较早的研究中期、东部经度、较老的平均年龄、较高的室外温度以及个人与住宅外 PM2.5 差值较低,与参与者内在的住宅外个人 PM2.5 相关性增加相关。
这些发现与同时进行的一项元分析相似,该分析检查了环境个人 PM2.5 相关性(rj = 中位数 0.54;范围 0.09-0.83)。总体而言,这些元分析表明,在评估 PM2.5 介导的健康影响研究中,住宅外个人 PM2.5 与环境个人 PM2.5 相关性值得进一步考虑。