Knox E G
Br J Ind Med. 1973 Jan;30(1):54-63. doi: 10.1136/oem.30.1.54.
54-63. A computer simulation system for a range of industrial hazards provided for model experiments which manipulated () the sub-structure of an exposed population in terms of age-distributions and levels of exposure, () the nature of the dose/response relationship, () the latent interval and its variability, () normal life-table expectations, and () employment turnover rates. The development of the system led to clarification of terms and concepts with ambiguous current usages, notably in relation to latency. Distinction is made between the notions of biological' and observable' latent intervals. Hypothetical exercises with the model tested its technical validity and at the same time demonstrated in quantitative terms the relationships between biological' and observable' latent intervals, employment turnover rates, total mortalities, and the distribution of illnesses and death between those currently employed in the exposing industry, those employed elsewhere, and those retired. Prospects of success for personnel engineering techniques, which manipulate age-distributions of exposed work people in relation to diseases with long latent intervals, were examined. Published asbestos cancer data were used as a basis for specific model fitting and resulted in a numerical formulation of the exposure/response relationships. Severe exposure results in an increment of risk of death of about 0·02 unit per person per annum for those exposed for around six years, but with higher rates for shorter exposures and lower rates for longer ones. The mean biological latent interval was about 25 years with a coefficient of variation of about 25%. These suppositions explained a range of published data comprehensively and at the same time predicted that () persons exposed at severe levels for a working lifetime of 50 years have a 40% risk of dying from asbestos cancer, and () industrial populations with moderate to high turnover rates effect a form of extended dose sharing, and non-linearity of the exposure/response relationship results in substantially more deaths than would be the case if the turnover rate were lower.
54 - 63. 一个针对一系列工业危害的计算机模拟系统，用于进行模型实验，这些实验可操控：（1）暴露人群按年龄分布和暴露水平划分的子结构；（2）剂量反应关系的性质；（3）潜伏期及其变异性；（4）正常生命表预期；（5）人员更替率。该系统的开发使得当前使用存在歧义的术语和概念得到了澄清，尤其是与潜伏期相关的内容。明确区分了“生物学”潜伏期和“可观察”潜伏期的概念。利用该模型进行的假设性实验检验了其技术有效性，同时从数量上展示了“生物学”潜伏期和“可观察”潜伏期、人员更替率、总死亡率以及暴露行业当前在职人员、其他行业在职人员和退休人员之间疾病与死亡分布之间的关系。研究了人员工程技术（即针对潜伏期较长的疾病操控暴露工人年龄分布）的成功前景。已发表的石棉癌数据被用作特定模型拟合的基础，得出了暴露/反应关系的数值公式。对于暴露约六年的人群，严重暴露导致每年每人死亡风险增加约0.02单位，但暴露时间较短时风险率较高，暴露时间较长时风险率较低。平均生物学潜伏期约为25年，变异系数约为25%。这些假设全面解释了一系列已发表的数据，同时预测：（1）在严重水平下暴露50年工作寿命的人员有40%的死于石棉癌的风险；（2）人员更替率中等至高的工业人群会产生一种延长剂量分担的形式，并且暴露/反应关系的非线性导致的死亡人数比人员更替率较低时要多得多。
