Reforming the workers' compensation process for occupational lung disease among miners in South Africa: an efficiency study of claims assessment.

PURPOSE: The large burden of silicosis and tuberculosis (TB) in the South African mining industry, coupled with an under-resourcing of the compensation agencies responsible for certifying occupational lung disease, have resulted in serious backlogs. This work aimed to measure the efficiency gains from triaging occupational lung disease claims using claim type, years of mining exposure and computer aided detection (CAD) to save on scarce medical adjudicators. METHODS: During 2020, the compensation authority started to triage claims for TB and those of miners with < 10 years of service to two-person panels instead of the four-person panel plus radiologist used previously. Efficiency gain was calculated in medical person-units saved and reduction in delays. Different service thresholds predictive of silicosis were simulated, as well as the impact of pre-classification of chest X-rays with CAD using different combinations of sensitivity and specificity. RESULTS: The new triage system saved 20.3% in person-time units and reduced delays by 10-20 days. Without CAD the greatest efficiency gain (28%) was projected from dispensing with a mining service threshold and routing all non-TB claims to the small panels at the outset. Simulation of four different CAD sensitivity/specificity combinations yielded efficiency gains of 18.2-36.1%, with 31.1% judged the most realistic. Use of sensitivity of close to 100% would not be feasible because of the very low resulting specificity. CONCLUSION: Pre-adjudication triage of claims at the compensation agency is capable of saving a substantial proportion of adjudicator time and reducing certification delays. Additional efficiency gains are achievable by referring all claims to small panels to begin with and improvement of CAD performance for this ex-miner population.

Computer-aided detection for tuberculosis and silicosis in chest radiographs of gold miners of South Africa.

BACKGROUND: For over one hundred years, the gold mining sector has been a considerable source of tuberculosis (TB) and silicosis disease burden across Southern Africa. Reading chest radiographs (CXRs) is an expert and time-intensive process necessary for the screening and diagnosis of lung disease and the provision of evidence for compensation claims. Our study explores the use of computer-aided detection (CAD) of TB and silicosis in CXRs of a population with a high incidence of both diseases.METHODS: A set of 330 CXRs with human expert-determined classifications of silicosis, TB, silcotuberculosis and normal were provided to four health technology companies. The ability of each of their respective CAD systems to predict disease was assessed using receiver operating characteristic curve analysis of the under the curve metric.RESULTS: Three of the four systems differentiated accurately between TB and normal images, while two differentiated accurately between silicosis and normal images. Inclusion of silicotuberculosis images reduced each system's ability to detect either disease. In differentiating between any abnormal from normal CXR, the most accurate system achieved both a sensitivity and specificity of 98.2%.CONCLUSION: The current ability of CAD to differentiate between TB and silicosis is limited, but its use as a mass screening tool for both diseases shows considerable promise.

Tuberculosis in commerce and industry in a Western Cape suburb, South Africa, 1987.

A postal questionnaire of 557 industries in a defined area of the Western Cape, South Africa, aimed to determine the incidence of pulmonary tuberculosis (TB) in 1987 as well as the provision of health services. A 65% response rate was obtained. A random sample of non-respondents did not differ from respondents with respect to factory size or sector. The overall incidence rate for 1987 was 472 per 100,000 workers (95% confidence interval 386-558). Tuberculosis rates of Africans and "coloureds" were substantially higher than those of Asians and whites. There was considerable variation in the rates by employment sector. We found highest rates of TB in the textile and iron and steel industries and the lowest rates are reported among the printing and paper industry, in trade and commerce, and in the transport sectors. It is likely that the differences in the rates by sector reflect the different social class composition of their work force. TB incidence rates also varied by factory size, with the highest rates being reported in the smallest factories. The implications of the study are that the current policy of not screening workers in industry on a routine basis for TB needs to be urgently reviewed. The provision of health services, shown to vary according to factory size, was found to be inadequate in the smaller factories. Alternative methods of providing such care to workers need to be implemented.

Ocular health status of chemical industrial workers.

BACKGROUND: Approximately 1.2 million workers are employed within chemical industries throughout South Africa. Very little basic data exists regarding the ocular health status and prevalence of occupationally related eye disorders of these workers. METHOD: A questionnaire was administered and an ocular health examination was carried out on 78 workers in a chemical factory. Workers and the ocular disorders found were then classified according to those exposed and those not exposed to chemicals. RESULTS: Ocular disorders were more prevalent in exposed workers (73.1%) than in nonexposed workers (43.6%). Statistically significant differences between exposed and nonexposed workers were found with respect to the prevalence of certain anterior segment disorders, viz., tear disorders, dry eye conditions, allergic conjunctivitis, and conjunctival melanosis. In respect to the prevalence of ocular disorders found, 40.8% were attributed to occupational exposure to chemicals. CONCLUSION: This pilot study shows that further research is required to explore the cause-effect relation between chemical exposure and development of certain anterior segment disorders. Occupational exposure to chemicals should be reduced and exposure protocols at work need to be revised in order to reduce the prevalence of occupationally related eye disorders.