Agreement of occupation and industry data on Rhode Island death certificates with two alternative sources of information

There is increasing interest in documenting the putative health effects of occupational hazards, prompting Federal and State efforts that rely primarily on occupational information obtained from the death certificate. Previous studies have assessed the agreement of occupational data on death certificates with actual lifetime employment by using current employment data from census records for comparisons. Such analyses have largely been confined to males. We compared lifetime occupational information obtained from a panel survey for both sexes with death certificate data for 446 deceased panel members. After adjusting for inadequate information, the occupation recorded on the death certificates of the men agreed with the occupation recorded in the survey 66 percent of the time. The comparable percentage for the industry where the deceased had been employed was 78 percent. Among the women's records, agreement on occupation was 65 percent, and on industry, 69 percent. Using another sample of death certificates, comparisons of the information for 322 decedents with city directory data produced similar results. The higher level of agreement for women was due in part to the large number who were reported as "housewives." In a separate analysis, the agreement rate for nonhousewives declined. Suggestions for improvements in the recording of occupational data and the constraints imposed by the use of death certificate data in occupational epidemiology are presented.     

An assessment of occupation and industry data from death certificates and hospital medical records for population-based cancer surveillance

This study analyzed 30,194 incident cases and 4,301 death certificates for completeness of occupational reporting. Analysis of data accuracy was based upon a comparison of more than 2,000 death certificates with incident abstracts and 352 death certificates with interview data. Death certificates had a higher proportion with occupation (94.3%) and industry (93.4%) reported than did incident abstracts of hospital medical records (39.0% and 63.5%, respectively). Compared with occupational history data obtained by interview, 76.1% of the death certificates were exact matches for usual occupation and industry.     

Representativeness of deaths identified through the injury-at-work item on the death certificate: implications for surveillance.

BACKGROUND. This research investigated the accuracy of the injury-at-work item on the death certificate for surveillance of occupational injury deaths in Oklahoma during 1985 and 1986. METHODS. Representativeness of occupational injury deaths identified by death certificates was assessed by comparing these deaths with all occupational injury deaths identified through death certificates, workers' compensation reports, medical examiner reports, and OSHA records for categories of occupation, industry, and external causes of death. RESULTS. Certain external causes of death (e.g., motor vehicle traffic deaths) and certain occupations (e.g., farming) and industries (agriculture and services) are more often underidentified through death certificates. CONCLUSIONS. The findings of this study support Baker's observation that no single data source contains all deaths or all the data elements necessary to describe occupational injury deaths. Data sources may be combined to improve representativeness through more complete case ascertainment.     

Organic solvents and presenile dementia: a case referent study using death certificates

Occupational exposure to organic solvents has been implicated in the development of "presenile dementia" in several studies. The death certificates of all men aged under 65 dying in England and Wales bearing presenile dementia as cause of death were collected for the years 1970-9 (n = 557): control death certificates were obtained, matched for age and sex. No significant differences were found between the groups as regards estimated occupational exposure to either organic solvents or lead.     

Organic solvents and presenile dementia: a case referent study using death certificates.

Occupational exposure to organic solvents has been implicated in the development of "presenile dementia" in several studies. The death certificates of all men aged under 65 dying in England and Wales bearing presenile dementia as cause of death were collected for the years 1970-9 (n = 557): control death certificates were obtained, matched for age and sex. No significant differences were found between the groups as regards estimated occupational exposure to either organic solvents or lead.     

A comparison of occupational data from death certificates and interviews

A comparison was made of the occupational data reported on the death certificates of 586 men with their employment history obtained by interviews. Agreement was assessed for 19 occupational and 14 industrial categories of usual employment, with the highest levels of concordance (greater than or equal to 80%) found for agricultural, medical, and public administration activities. Between the two sources of information, there was overall agreement of 56% for usual occupation and 51% for usual industry of employment. Concordance was highest among the 68 self-respondents (usual occupation 66%; usual industry 53%). Among the 518 surrogates, spousal agreement was highest (58% for occupation and 51% for industry). For other surrogate types, agreement was 49% for both industry and occupation. Agreement varied by duration of employment and by level of education, with concordance tending to increase as length of employment and educational attainment rose. These relationships remained when examined by respondent type. Evaluation of agreement levels by age and other study subject characteristics showed little effect on concordance. Review of verbatim data from the interviews and death certificates revealed that most disagreements could be attributed to coding problems caused by vague or misleading information on the death certificates, although some disconcordance was due to uncodable and missing information in the interview history. Based on results from this and prior studies, the value of occupational data derived from death certificates in epidemiologic studies may be limited, although the addition of explicit instructions on the death certificate itself may aid in providing more useful and complete information for usual employment.     

Occupational disease surveillance data sources, 1985.

Health department epidemiologists in 50 states, New York City, and the District of Columbia were surveyed in 1985 about seven potential data sources for occupational disease surveillance. Reported sources of occupational disease data were: automated workers' compensation claims (63 per cent of the 52 respondents); provider reports (62 per cent); death certificates with occupation or industry (60 per cent); cancer registries with occupational histories (35 per cent); birth certificates with parent's occupation (27 per cent); non-cancer disease registries (13 per cent); and hospital or insurance records (8 per cent).     

Sentinel health event surveillance: skin cancer of the scrotum in New York State.

Skin cancer of the scrotum is a disease that has been identified as a sentinel health event (occupational) (SHE(O] that is necessarily occupationally related. The present paper examines the feasibility of using this disease in active cancer surveillance in New York State. After consulting cancer case reports, hospital records, death certificates, and city directories, we obtained occupational data for 17 of 22 cases of nonmelanoma skin cancer of the scrotum diagnosed between 1979 and 1984. Only three cases had occupations previously linked to scrotal cancer, while 11 of 19 cases had one or more possibly contributory medical conditions. The probable under-reporting of scrotal cancer cases and incompleteness of occupational data may limit the usefulness of scrotal cancer as a sentinel health event (occupational) unless additional steps are taken.     

Death certificates in epidemiological studies, including occupational hazards: inaccuracies in occupational categories.

We compared death certificates for asbestos-associated diseases (mesothelioma, lung cancer, asbestosis) in two asbestos workers' cohorts. One (insulation workers) had current or recent employment and a strong, continuing union support system which gave them much information about the effects of asbestos exposure. The second cohort, asbestos factory workers, had no such advantage. The factory had closed almost 30 years before, and its workers had dispersed into many areas of the state and nation. Accuracy of medical diagnosis was comparable in the two groups, but occupational listings were not. Three-quarters of the insulators' death certificates told of asbestos work, while virtually none of the factory workers' certificates provided such information, even for deaths of mesothelioma and asbestosis. The data indicate that disease categories, based on medical and pathological diagnoses, at least for asbestos-associated disease, tend to be accurate. Attempts to identify groups at risk by sorting occupational categories can give variable results, good for those with current exposures, much less satisfactory for those with long-past occupational exposures.     

Occupation recorded on certificates of death compared with self-report: the Atherosclerosis Risk in Communities (ARIC) Study

Background  

Death certificates are a potential source of sociodemographic data for decedents in epidemiologic research. However, because this information is provided by the next-of-kin or other proxies, there are concerns about validity. Our objective was to assess the agreement of job titles and occupational categories derived from death certificates with that self-reported in mid and later life.     

A case-control study of bladder cancer using city directories as a source of occupational data

Commercial city directories, currently produced in 1,250 United States cities, potentially provide yearly information on occupation and employer for all city residents over age 18 years. To investigate the usefulness of these occupational data, the authors have conducted a case-control study of male bladder cancer mortality in Hamilton County, Ohio (which includes Cincinnati). A total of 731 bladder cancer cases who died during 1960-1982 were matched on age, sex, race, date-of-death, and residence at death to two controls per case. Risks of bladder cancer death were calculated by occupation, industry, and specific employer, using both city directories (multiple statements) and death certificates (single statement). Four companies showed a significant excess bladder cancer risk when using city directories. Only one would have been identified using death certificates, which ask for usual lifetime type of industry rather than a specific company name. Using city directories, significant positive associations were found between bladder cancer and occupation as an engineer, tailor, carpenter, furnace operator, blending machine operator, chemist, pressing machine operator, house cleaner, or salesman. For industry, the authors found significant positive associations for the textile, chemical, grain mill, foundry, petroleum, building service, entertainment, and advertising industries. A significant increase in risk for those with 20 or more years of employment was seen for those employed as truck drivers and furnace operators, or those employed in the railroad industry. A check of the validity of city directory data indicated that 77 per cent of the listings agreed with Social Security earnings reports for employer in any given year. One limitation of Hamilton County city directory data was the fairly large number of yearly listings without any occupational data (15 per cent for occupation, 36 per cent for employer). While city directory data do provide work history over time, unlike death certificates, such data are available only for years of residence in the city in question.     

Correcting for numerator/denominator bias when assessing changing inequalities in occupational class mortality, Australia 1981 -2002

OBJECTIVE: Comparisons of the changing patterns of inequalities in occupational mortality provide one way to monitor the achievement of equity goals. However, previous comparisons have not corrected for numerator/denominator bias, which is a consequence of the different ways in which occupational details are recorded on death certificates and on census forms. The objective of this study was to measure the impact of this bias on mortality rates and ratios over time. METHODS: Using data provided by the Australian Bureau of Statistics, we examined the evidence for bias over the period 1981 -2002, and used imputation methods to adjust for this bias. We compared unadjusted with imputed rates of mortality for manual/non-manual workers. FINDINGS: Unadjusted data indicate increasing inequality in the age-adjusted rates of mortality for manual/non-manual workers during 1981 -2002. Imputed data suggest that there have been modest fluctuations in the ratios of mortality for manual/non-manual workers during this time, but with evidence that inequalities have increased only in recent years and are now at historic highs. CONCLUSION: We found that imputation for missing data leads to changes in estimates of inequalities related to social class in mortality for some years but not for others. Occupational class comparisons should be imputed or otherwise adjusted for missing data on census or death certificates.     

Occupation and industry on death certificates of long-term chemical workers: concordance with work history records

This study evaluated the concordance between occupation and industry listed on death certificates with actual work history information for a group (n = 5,882) of long-term (10 years or more) workers at a chemical company. Match rates were calculated as the percent of death certificate occupation and company entries that were confirmed by work history data using 3-digit 1980 U.S. Census Bureau group codes. The concordance rate for industry differed by employment status at death: employed, 94.9%; inactive, 30.8%; and retired, 91.1%. Concordance on occupation was analyzed for employed (n = 467) and retired (n = 932) subjects who had computerized work histories (randomly done prior to the study) and who had matched on the company on the death certificate. Concordance ranged from 0 to 50% for the first job, to 50 to 70% for the last job, longest job, and longest job in the last 10 years of company employment. The most consistent predictor of concordance was job duration. Misclassification was reviewed by occupational category. Results from this and other investigations lead to the inevitable conclusion that usual occupation data from death certificates are grossly inadequate for studies of occupational risks.     

Occupational information on death certificates: a survey of state practices.

A national survey was conducted in 1979 to determine the extent to which state and local vital registration offices coded and stored occupational information reported on death certificates. This survey found that 11 states routinely code occupation, seven routinely code industry, and six have coded occupation and/or industry on a limited basis. State and federal cooperation is needed to facilitate increased use of mortality data for environmental and occupational health research.     

Estimating the total number of newly-recognized silicosis cases in the United States

BACKGROUND: The US employer-based surveillance system for documenting occupational injuries and illnesses undercounts chronic diseases. We suggest a method to estimate the number of individuals who are newly-recognized with silicosis each year in the United States. METHODS: Data from US death certificates, the Michigan state-based surveillance system, and capture-recapture analysis were used to calculate national estimates of silicosis. RESULTS: From 1987 to 1996, 2,787 deaths occurred in the United States where silicosis was mentioned on the death certificates. During the same period, in Michigan 77% of death certificates with a mention of silicosis were confirmed as silicosis-related deaths and the ratio of the number of living to deceased confirmed silicosis cases was 6.44. The proportion of confirmed silicosis deaths, the ratio of the living to deceased silicosis cases and capture-recapture analysis from the Michigan surveillance system, were used to estimate that there were 3,600-7,300 cases per year of silicosis in the United States from 1987 to 1996. CONCLUSIONS: Our estimate of the annual number of newly-recognized silicosis cases is significantly larger than the estimate from the employer-based reporting system used for counting occupational disease in the United States. This employer-based surveillance system is inadequate for determining the frequency of occupational disease. Our analysis which combines a readily-available and relatively inexpensive national administrative database (i.e., death certificates) with a more costly state-based active surveillance system is a cost-effective model that could be used to provide better estimates of a number of different occupational diseases. Accurate estimates of occupational illnesses are essential to both determine temporal trends and evaluate efforts to prevent silicosis.     

Risk factors associated with the classification of unspecified and/or unexplained causes of death in an occupational cohort.

In a matched case-control study of an occupational cohort in East Tennessee, data from the death certificates of 608 cases and controls were abstracted and analyzed in order to investigate possible risk factors associated with the certification on the death certificate of an ill-defined cause of death. There was a very strong association between the ill-defined classification and the certifier, especially if the certifier was a medical examiner (OR = 10.4, 95% CI: 6.0, 18.0).     

Reporting of diabetes on death certificates of 1872 people with type 2 diabetes in Tayside, Scotland

BACKGROUND: It has been suggested that diabetes is under-recorded on death certificates. METHODS: We examined the death certificates of 1,872 people with type 2 diabetes in Tayside, Scotland, to determine how frequently diabetes was recorded. RESULTS: Diabetes was mentioned on the certificates of 42.8% and was the underlying cause of death for 6.4%. There was mention of diabetes for 51.3% of the 811 people for whom cardiovascular disease was the underlying cause of death. Being male was associated with less frequent mention of diabetes, with more frequent mention associated with increasing duration of diabetes, increasing age and underlying cardiovascular cause of death. CONCLUSIONS: This study highlights the limitations of using routine mortality data for monitoring the burden of diabetes in populations.     

Cost-effectiveness of hospital discharge records for reaching selected endpoints in the surveillance of silicosis

Background The Sentinel Event Notification System for Occupational Risks (SENSOR) is a state/federal system for the surveillance and intervention of occupational conditions. The Ohio SENSOR program identifies silicosis cases from a number of data sources, although hospital discharge records have largely been considered the most successful means of carrying out SENSOR objectives. However, the cost-effectiveness of hospital discharge records has not been evaluated. Thus, a cost analysis was conducted to compare the effectiveness of hospital discharge records with other data sources for achieving prevention-related endpoints of silicosis surveillance. Methods Total costs of reaching three endpoints (obtaining case names, identifying work sites, and identifying silica problems in work sites) were estimated retrospectively and measured in 1996 dollars for four data sources: hospital discharge records, physician reports, workers' compensation claims, and death certificates. Total costs were then divided by output for each source/endpoint combination to produce estimates of average costs. Results The average cost per case was $30 for hospital records, $212 for physician reports, $19 for workers' compensation claims, and $7 for death certificates. However, for identifying problem work sites, hospital records were most expensive at $2,883 per work site, compared with $2,558 for physician reports, $1,318 for workers' compensation claims, and $1,310 for death certificates. Conclusions Hospital discharge records were least cost-effective for accomplishing prevention-related goals of surveillance. A change in the mix of resources applied to silicosis surveillance and intervention under SENSOR, i.e., a shift away from follow-up of hospital records toward more cost-effective methods for identifying work sites with silica problems may result in more efficient use of public health resources devoted to the prevention of silicosis. Am. J. Ind. Med. 34:484–492, 1998. © 1998 Wiley-Liss, Inc.     

The use of sentinel injury deaths to evaluate the quality of multiple source reporting for occupational injuries

PURPOSE: This study sought to develop an efficient method for evaluating the validity and completeness of routinely available sources of occupational injury fatality data. METHODS: Deaths due to falls from elevations, machinery, and electrocutions were selected as sentinel injuries likely to have occurred at work. Deaths from these injuries were identified from Maryland vital statistics over 7 years. The work-relatedness of these injuries and sensitivity of reporting were determined from death certificates, medical examiner reports, the National Traumatic Occupational Fatality System (NTOF), the Maryland Occupational Safety and Health Administration (MOSH), and Workers' Compensation (WC) data. RESULTS: A total of 527 deaths were identified for ages 16 and above, of which, 45% were work-related. Identification of work-related deaths varied by source: medical examiner (100%), death certificates (89%), NTOF (68%), MOSH (59%), and WC (44%). Reporting differed by age, cause of injury, year, occupation, and industry. CONCLUSIONS: Examination of work-relatedness for deaths from certain causes is an efficient means of evaluating the quality of occupational injury reporting source data. These sentinel injuries uncovered significant underreporting in sources used by national surveillance systems, resulted in improved NTOF reporting, and suggest the need to make more use of medical examiner data when available.     

Der Bremer Mortalitätsindex

The Bremen Mortality Index (BreMI) is an electronic data file providing all information found on death certificates of former Bremen citizens who have died after December 31, 1997. BreMI follows the example of the National Death Index (NDI) in the USA, which has provided information on the vital status of US citizens and cause of death since 1979. The Bremen Mortality Index has been linked successfully to the Bremen Cancer Registry and has improved the efficiency of following up cancer patients. A substantial number of death certificates may be checked automatically for the presence of a cancer diagnosis or any other diagnosis. The Bremen Mortality Index may be used as a primary source for data on particular causes of death. It will be used for developing a German thesaurus for automated coding of medical entities and for determining causes of death.