School of Public Health, Drexel University, 1505 Race Street, MS 1034, Philadelphia, PA 19102, USA.
Int J Environ Res Public Health. 2012 Apr;9(4):1216-26. doi: 10.3390/ijerph9041216. Epub 2012 Apr 11.
The Philadelphia Lead Safe Homes (LSH) Study was designed to evaluate whether educational and environmental interventions in the first year of life for families of newborns increased knowledge of lead exposure prevention and were associated with less elevation of blood lead levels (BLLs) for these children, when compared to children receiving standard care.
The current study performed descriptive statistics on the second-year BLL data for both groups and compared these using chi-square tests for proportions and unpaired t-tests for means.
A BLL result was found for 159 (50.6%) of the 314 LSH cohort children and 331 (52.7%) of the 628 control children (p = 0.1). Mean and standard deviation for age at draw was 23.8 (3.4) months versus 23.6 (3.1) months (P = 0.6). Geometric mean BLLs were 3.7 versus 3.5 µg/dL (P = 0.4). The percentages of the cohort group with a BLL of ≥ 20, ≥ 10 and ≥ 5 μg/dL, respectively, were 0.6%, 5% and 30%; for the controls 1.2%, 6.6%, and 25%. These percentages were not significantly different between groups.
A comparison of geometric mean BLLs and percentages above several BLL cut points drawn at age two years in a group of urban newborns benefitting from study interventions versus a group of similar urban children did not yield statistically significant differences. Both groups had relatively lower lead levels when compared to historical cohort groups, which may reflect a continuing downward trend in BLLs in U.S. children. The interventions did result in benefits to the families such as an increase in parental knowledge about lead exposure prevention and in-home wet cleaning activity, and a decrease in lead dust levels in study homes.
费城铅安全家园（LSH）研究旨在评估在新生儿家庭的生命的第一年中，教育和环境干预措施是否增加了对铅暴露预防的认识，并与接受标准护理的儿童相比，是否与这些儿童的血铅水平（BLL）升高减少有关。
本研究对两组儿童的第二年 BLL 数据进行了描述性统计，并使用比例的卡方检验和均值的未配对 t 检验对这些数据进行了比较。
在 LSH 队列的 314 名儿童和对照组的 628 名儿童中，有 159 名（50.6%）和 331 名（52.7%）儿童的 BLL 结果（p = 0.1）。抽取时的年龄平均值和标准差分别为 23.8（3.4）个月和 23.6（3.1）个月（P = 0.6）。几何平均 BLL 分别为 3.7 和 3.5 µg/dL（P = 0.4）。队列组中 BLL 分别为≥20、≥10 和≥5 µg/dL 的百分比分别为 0.6%、5%和 30%；对照组分别为 1.2%、6.6%和 25%。两组之间的百分比无显著性差异。
在接受研究干预的一组城市新生儿与一组类似的城市儿童相比，比较两岁时的几何平均 BLL 和几个 BLL 切点以上的百分比，并没有得出统计学上的显著差异。与历史队列组相比，两组的血铅水平相对较低，这可能反映了美国儿童血铅水平的持续下降趋势。这些干预措施确实为家庭带来了好处，例如增加了父母对铅暴露预防的认识以及家庭内湿清洁活动，并降低了研究家庭中的铅尘水平。
