Division of Occupational Medicine, School of Public Health and Family Medicine, University of Cape Town, Cape Town 7925, South Africa.
School of Population and Public Health, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
Int J Environ Res Public Health. 2022 Mar 17;19(6):3562. doi: 10.3390/ijerph19063562.
In the wake of a large burden of silicosis and tuberculosis among ex-miners from the South African gold mining industry, several programmes have been engaged in examining and compensating those at risk of these diseases. Availability of a database from one such programme, the Q(h)ubeka Trust, provided an opportunity to examine the accuracy of length of service in predicting compensable silicosis, and the concordance between self-reported employment and that officially recorded. Compensable silicosis was determined by expert panels, with ILO profusion ≥1/0 as the threshold for compensability. Age, officially recorded and self-reported years of service, and years since first and last service of 3146 claimants for compensable silicosis were analysed. Self-reported and recorded service were moderately correlated (R = 0.66, 95% confidence interval 0.64−0.68), with a Bland−Altman plot showing no systematic bias. There was reasonably high agreement with 75% of the differences being less than two years. Logistic regression and receiver operating characteristic curve analysis were used to test prediction of compensable silicosis. There was little predictive difference between length of service on its own and a model adjusting for length of service, age, and years since last exposure. Predictive accuracy was moderate, with significant potential misclassification. Twenty percent of claimants with compensable silicosis had a length of service <10 years; in almost all these claims, the interval between last exposure and the claim was 10 years or more. In conclusion, self-reported service length in the absence of an official service record could be accepted in claims with compatible clinical findings. Length of service offers, at best, moderate predictive capability for silicosis. Relatively short service compensable silicosis, when combined with at least 10 years since last exposure, was not uncommon.
在南非金矿开采业中，大量的矽肺和肺结核矿工面临着沉重的负担，因此开展了多项计划来检查和补偿那些处于患病风险中的矿工。其中一个名为 Q(h)ubeka 信托的计划的数据库为我们提供了一个机会，来检验服务年限对矽肺的预测准确性，以及自我报告的就业情况与官方记录的一致性。补偿性矽肺是由专家小组确定的，ILO 密集度≥1/0 作为补偿的阈值。对 3146 名补偿性矽肺索赔者的年龄、官方记录和自我报告的服务年限以及首次和最后一次服务年限进行了分析。自我报告的服务年限和记录的服务年限中度相关（R=0.66，95%置信区间为 0.64-0.68），Bland-Altman 图显示没有系统偏差。差异小于两年的比例为 75%，具有较高的一致性。逻辑回归和受试者工作特征曲线分析用于测试补偿性矽肺的预测。单独使用服务年限和调整服务年限、年龄和最后一次接触后的年限的模型进行预测，差异不大。预测准确性中等，存在显著的潜在误分类。20%的补偿性矽肺索赔者的服务年限<10 年；在几乎所有这些索赔中，最后一次接触和索赔之间的间隔为 10 年或更长。总之，在没有官方服务记录的情况下，自我报告的服务年限可以在与临床发现相符的索赔中被接受。服务年限提供了矽肺的中度预测能力。相对较短的服务年限且至少 10 年未接触矽尘，这并不罕见。
