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J Beaumont

Publications and source records attributed to J Beaumont.

29 records · Page 2Linked to original sources
PubMed1990

New developments in the Life Table Analysis System of the National Institute for Occupational Safety and Health.

In the 1970s, the National Institute for Occupational Safety and Health developed a Life Table Analysis System to analyze occupational cohort studies. We have updated the original system by adding two new features: direct standardization with a test for linear trend, and analyses by lagged exposure (either duration of exposure or cumulative exposure). We have also updated US reference rates through 1989. The updated systems and documentation (version F) are available upon request. In collaboration with the National Cancer Institute, we have also developed multiple cause-of-death rate files, which consider contributory as well as underlying cause. These files (also available upon request) will enable investigators to derive the expected prevalence of diseases at death, which can then be compared with the observed prevalence in an exposed cohort. Work is currently underway to produce a personal computer version of the Life Table Analysis System.

Cause of Death↗
PubMed1989

Further follow-up and adjustment for smoking in a study of lung cancer and acid mists.

Follow-up of a cohort of 1,165 steelworkers exposed to acid mists has been extended from 1981 to early 1986 for most cohort members, and information on smoking has also been collected. We obtained an SMR for lung cancer (unadjusted for smoking) of 1.56 (95% CI 1.12-2.11, 41 observed). For those with 20 years or more since first exposure, the SMR was 1.72 (1.21-2.39). However, no trend was found with duration of exposure. To adjust for smoking, we used an indirect adjustment as suggested by Axelson to account for the fact that the exposed cohort smoked slightly more than the U.S. referent population. The SMR for the whole cohort dropped to 1.36 (0.97-1.84), while for those with more than 20 years since first exposure, the SMR was 1.50 (1.05-2.07). These results indicate that an excess risk for lung cancer persists after control for confounding by smoking.

Aerosols↗
PubMed1988

Mortality among California highway workers.

Standardized proportional mortality ratios (PMR) were computed for a population of highway workers. Hazards of highway maintenance work include exposure to solvents, herbicides, asphalt and welding fumes, diesel and auto exhaust, asbestos, abrasive dusts, hazardous material spills, and moving motor vehicles. Underlying cause of death was obtained for 1,570 workers who separated from the California Department of Transportation between 1970 and 1983, and who died in California between 1970 and 1983 (inclusive). Among 1,260 white males, the major findings were statistically significant excesses of cancers of digestive organs (PMR = 128), skin (PMR = 218), lymphopoietic cancer (PMR = 157), benign neoplasms (PMR = 343), motor vehicle accidents (PMR = 141), and suicide (PMR = 154). Black males (N = 66) experienced nonsignificant excesses of cancer of the digestive organs (PMR = 191) and arteriosclerotic heart disease (PMR = 143). Among 168 white females, deaths from lung cancer (PMR = 189) and suicide (PMR = 215) were elevated. White male retirees, a subgroup with 5 or more years of service, experienced excess mortality due to cancers of the colon (PMR = 245), skin (PMR = 738), brain (PMR = 556), and lymphosarcomas and reticulosarcomas (PMR = 514). Deaths from external causes (PMR = 135) and cirrhosis of the liver (PMR = 229) were elevated among white males with a last job in landscape maintenance. White males whose last job was highway maintenance experienced a deficit in mortality from circulatory diseases (PMR = 83) and excess mortality from emphysema (PMR = 250) and motor vehicle accidents (PMR = 196). Further epidemiologic and industrial hygiene studies are needed to confirm the apparent excess mortality and to quantify occupational and nonoccupational exposures. However, reduction of recognized hazards among highway maintenance workers is a prudent precautionary measure.

Accidents, Occupational↗
PubMed1988

Intraocular lens implantation: a model for the Third World.

Intracapsular cataract extraction has long been thought of as the appropriate technique to deal with the backlog of Third World cataract blindness. However, this operation may not be as sight effective as many believe. The authors offer their experience of intraocular lens implantation in the Torres Strait as a model for a more visually appropriate surgical cure for Third World cataract.

Cataract Extraction↗
PubMed1988

Incidence of laryngeal cancer and exposure to acid mists.

To determine the relation between exposure to acid mist and laryngeal cancer, the smoking habits, drinking habits, and incidence of laryngeal cancer of 879 male steelworkers exposed to acid mists during pickling operations was ascertained. Sulphuric acid mist was the primary exposure for most men in this cohort. These men had all worked in a pickling operation for a minimum of six months before 1965, with an average duration of exposure of 9.5 years. Exposures to sulphuric acid in the 1970s averaged about 0.2 mg/m3, and earlier exposures were probably similar. Interviews were conducted with all cohort members or their next of kin in 1986 and medical records of decedents were reviewed. Nine workers were identified who had been diagnosed as having laryngeal cancer, using a conservative case definition that required medical record confirmation for any case among decedents and confirmation by a physician for any case among live individuals. Using data from national surveys of cancer incidence as referent rates, 3.44 laryngeal cancers would have been expected. Excess smoking by the exposed cohort compared with the United States population resulted in an upward adjustment of the expected number of cases of laryngeal cancer to 3.92. The standardised incidence rate ratio for laryngeal cancer was 2.30 (9/3.92), with a one sided p value of 0.01 (assuming a Poisson distribution). The finding of excess laryngeal cancer in this cohort is consistent with four other studies published since 1981.

Alcohol Drinking↗
PubMed1986

A proportionate mortality study of granite cutters.

Several recent studies (animal and human) have suggested an association between lung cancer and silica exposure. To test the hypothesis, we have studied death benefit records of 1,905 members of the Granite Cutters Union. A proportionate mortality analysis (PMR) was conducted, using U.S. deaths as a comparison population. Statistically (PMR) was conducted, using U.S. deaths as a comparison population. Statistically significant excesses were observed for death from nonmalignant respiratory significant excesses were observed for death from nonmalignant respiratory disease (largely silicosis) (183 obs, 43.7 exp) and for tuberculosis (largely silicotuberculosis) (262 obs, 19.3 exp). Other significant excesses were observed for bone cancer (6 obs, 1.9 exp) and arthritis (5 obs, 1.5 exp). A significant decrease was observed for leukemia (5 obs, 13.0 exp). For lung cancer a slight but nonsignificant excess was observed (97 obs, 81.1 exp, PMR = 1.19, 95% CI 0.97-1.46). A proportionate cancer mortality analysis (PCMR) showed similar results for lung cancer (PCMR = 1.09, 95% CI 0.89-1.33). Lung cancer mortality also failed to show any trend with either calendar time or duration of exposure. Although no significant excess of lung cancer was observed for the entire silica-exposed cohort, there was an indication that those who were silicotic had an excess risk of lung cancer, based on a review of contributing causes on the death certificate.

Construction Materials↗
PubMed1986

The use of regression analyses in a cohort mortality study of welders.

Using an internal nonexposed comparison group, and two types of regression analysis, we have reanalyzed the data from a cohort mortality study of 3247 welders and 5432 nonwelders who worked in Western Washington during the period 1950-1976. Previous analyses relied primarily on the standardized mortality ratio (SMR) for lung cancer as a summary statistic to estimate relative risk; welders were compared to the U.S. population, stratified by age, sex, race, and calendar time. In the present study, nonwelders from the same union were used as the reference group; an internal referent group is often preferable to the U.S. population, because it is likely to have shared similar lifestyles (e.g. smoking habits) as the exposed. Cox regression was used to estimate relative risk. In addition, the data was analyzed via logistic regression in order to compare Cox to logistic regression. A regression analysis of these data enabled us to analyze exposure as a continuous variable and simultaneously adjust for potentially confounding variables without stratification. Interactions terms could also be easily tested. The previous analysis found as SMR for lung cancer of 1.32 (p = 0.06). Cox regression with an internal comparison group yielded similar results. Issues discussed include the differences between logistic and Cox regression, the appropriate variable for time in Cox regression, and the definition of risk set in Cox regression. Finally, a newly available program is discussed which selects random samples of the risk sets used in Cox regression, in order to do a case-control analysis.

Age Factors↗
PubMed1984

Methods of control for smoking in occupational cohort mortality studies.

Cohort mortality studies, which compare the observed mortality of a historically exposed cohort to an expected mortality based on figures from a national population, are among the most common and useful types of studies done in occupational epidemiology. Such studies are primarily based on records which lack data on smoking. Hence it is often difficult to determine whether an observed excess of a given smoking-related disease is the result of occupational exposures, an excess consumption of cigarettes among the exposed, or an interaction between the two. The purpose of this paper is to outline the different types of control which may be exercised in cohort mortality studies to control for the effects of smoking. Indirect control, which uses only existing data, may be exercised through (i) analysis of other smoking-related causes of death besides the cause-of-death of primary interest, (ii) use of an internal reference group instead of the national population, (iii) adjustment of the excess risk based on hypothetical smoking habits, or (iv) analysis for a dose-response relationship between occupational exposure and disease. Direct control, which requires interviews, may be exercised through (i) a survey of the smoking habits of currently employed cohort members, (ii) a survey of all cohort members, or (iii) a "nested" case-referent study within the cohort. The choice of which method to use depends on the cost and the degree of accuracy required by the investigator.

Aged↗
PubMed1984

The accuracy of occupation and industry data on death certificates.

To assess the accuracy of occupation and industry data on death certificates, we compared the known occupation and industry of 3,789 individuals with information on their death certificates. All individuals were members of the National Institute for Occupational Safety and Health cohort studies and their occupation and industry were known from personnel or union records. We focused our analysis on 2,198 long-term workers who had 10 or more years of work experience (average, 18 years). Our principal finding was that for the long-term workers in our sample, the probability of the known occupation being listed on their death certificates was 64.7% (SE = 1.1) (for white workers this figure was 73.5% (SE = 1.2). Furthermore, for the long-term workers the probability of the plant or industry being named on their death certificates was 70.1% (SE = 1.2). Women and non-whites had lower matching rates. For women the probability of a matched listing was 45.1% for occupation and 60.4% for industry. For nonwhites, it was only 30.1% for occupation and 49.2% for industry. Our results for white long-term workers generally agree with the results of previous investigators who have used different methods.

Black or African American↗