Respiratory ill-health in dental laboratory technicians: a comparative study of GP consultation rates.

Eighteen Royal Air Force dental laboratory technicians (DLTs) and 69 Service controls matched for age, sex and smoking status were compared by means of incidence rates of GP consultation for respiratory, and all other, illness. By retrospectively calculating for each individual the time served (man-years at risk) at the RAF Station concerned, together with the number of consultations that fell into each of the study categories, it was possible to produce an incidence rate, per man-year at risk, of consultations for both study and control groups. By calculating a relative risk (RR) it was observed that DLTs were nearly three times (RR = 2.95. CI 1.69-5.13), more likely to attend their GP with respiratory problems than members of the control group, and 1.7 times (RR = 1.71. CI 0.98-3.01) more likely to attend their GP with other problems. Comparison of the numbers of individuals continuing to use bronchodilator therapy in each of the two groups suggested that DLTs have a higher prevalence of conditions that require this form of therapy as treatment.