Wolowich W R, Casavant M J, Fisher C A
Central Ohio Poison Center, Children's Hospital, Ohio State University, Columbus, USA.
J Toxicol Clin Toxicol. 2001;39(4):367-70. doi: 10.1081/clt-100105157.
The American Association of Poison Control Centers defines penetrance as the number of exposures per 1000 residents of a population during one year. This metric fails to account for confounding by age group variability. We demonstrate the error caused by using raw penetrance and present two alternate methods of calculation, age-specific penetrance and age-adjusted penetrance.
Data from the toxic exposure surveillance system were collected from calls to our 41 county regional poison centers in 1998. Age-specific penetrance (ASP) was calculated by dividing the number of exposures (E) in age interval "i" in county "A" by 1000 population in age interval "Pi" in county "A" or ASP = Ei/Pi. AAP is the summation of the weighted age-specific penetrance. Weights (w(si)) represent the relative age distribution of a standard population, in this case the 1998 US population. AAP = sigma(i) w(si) * Ei/Pi.
[table: see text] County C has low raw penetrance and is known to have relatively fewer toddlers and presumably a lower incidence of poisoning. This demonstrates that raw penetrance misrepresents populations with small proportions of children and should not be used to compare promotion or prevention activities between populations.
We recommend poison centers and the American Association of Poison Control Centers replace raw penetrance with age-adjusted penetrance as one measure of the effectiveness of a poison center's awareness efforts.
美国中毒控制中心协会将渗透率定义为一年内每1000名居民中的暴露次数。该指标未能考虑年龄组变异性造成的混杂因素。我们展示了使用原始渗透率所导致的误差，并提出了两种替代计算方法，即年龄特异性渗透率和年龄调整渗透率。
1998年从我们41个县的区域中毒控制中心接到的电话中收集了来自有毒暴露监测系统的数据。年龄特异性渗透率（ASP）通过将“A”县年龄区间“i”内的暴露次数（E）除以“A”县年龄区间“Pi”内的1000人口来计算，即ASP = Ei/Pi。年龄调整渗透率（AAP）是加权年龄特异性渗透率的总和。权重（w(si)）代表标准人群的相对年龄分布，在这种情况下是1998年美国人口。AAP = sigma(i) w(si) * Ei/Pi。
[表格：见正文] C县的原始渗透率较低，已知其学步儿童相对较少，中毒发生率可能也较低。这表明原始渗透率不能准确反映儿童比例小的人群情况，不应被用于比较不同人群之间的宣传或预防活动。
我们建议中毒控制中心和美国中毒控制中心协会用年龄调整渗透率取代原始渗透率，作为衡量中毒控制中心宣传工作成效的一项指标。
