OBJECTIVE--The survey aimed at studying the associations between prevalent respiratory symptoms in an occupational population and sickness absence due to respiratory disorders. METHODS--A cross ...sectional survey among male workers in an animal feed mill was conducted. A total of 303 production workers and 102 office clerks completed a questionnaire on respiratory complaints, smoking habits, and occupational history. The questionnaire was used to identify workers with respiratory symptoms in the past 12 months. During this period all spells of sickness absence were recorded. Causes of sickness were classified in broad categories encompassing respiratory symptoms, influenza, musculoskeletal disorders, and others. RESULTS--Logistic regression analysis showed that workers with respiratory complaints experienced a higher sickness absence than those without respiratory complaints. Adjusted for age and smoking the odds ratio (OR) for sickness prevalence was 1.9 among office clerks and 2.6 among blue collar workers. Smoking increased the risk on sickness absence with ORs of 2.4 and 1.6, respectively. When restricting the analysis to sickness due to respiratory complaints, subjects with respiratory complaints had significantly higher risks for absence prevalence and absence rate than those without respiratory complaints. There were no differences in sickness absence between workers with asthma like complaints and those with chronic bronchitis like complaints. CONCLUSION--The clear associations between respiratory complaints and prevalence and rate of respiratory sickness absence indicate that workers with respiratory complaints are at risk of temporary disability and, thus, may experience a reduced ability to cope with routine activities at work.
Compensation schemes for asbestos-related diseases have developed different strategies for attributing a specific disease to occupational exposure to asbestos in the past. In the absence of ...quantitative exposure information that allows a valid estimate of an individuals historical exposure, general guidelines are required to retrospectively evaluate asbestos exposure. A risk matrix has been developed that contains qualitative information on the proportion of workers exposed and the level of exposure in particular industries over time. Based on this risk matrix, stepwise decision trees were formulated for decisions regarding the decisive role of historical asbestos exposure in case ascertainment of asbestosis and mesothelioma. Application of decision schemes will serve to speed up the process of verifying compensation claims and also contribute to a uniform decision-making process in legal procedures.
Pulmonary lung-function testing plays an important role in surveillance programs for occupational respiratory disorders, Spirometry is usually utilized by applying preset cut-off values to ...disariminate between healthy and unhealthy subjects. This article demonstrates the usefulness of decision analysis techniques to arrive at an optimal diagnosis. The diagnostic performance of FEV₁ and FEV₁/FVC was evaluated by relative operating characteristics curves (ROCs) applied to data of a cohort gathered in 1965. Both parameters showed quite similar ROCs, with a maximal sensitivity of 40% at a specificity of 95 % relative to the physician's diagnosis of respiratory disorder. The area under the curves was .75 for both FEV₁ and FEV₁/FVC, illustrating that misclassification of 25 % of the subjects is likely to occur. Regarding the consequences of a false-positive and a false-negative decision as of equal importance, the 5%-percentih (FEVj residual less than — 1.2 L) would be the optimal cut-off. An FEV₁ residual below the lower 5%-percentile was six times more likely to appear in subjects with chronic nonspecific lung disease (CNSLD) than in subjects without. The post-test probability of CNSLD was three to four times the pre-test probability. In occupational or public health practice, however, false-positive results need to be avoided, even at the expense of a higher false-negative rate. In those situations, a more rigid cut-off between normal and abnormal values may be warranted.