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Work-Related Lung Disease Surveillance System (eWoRLD)

Sources of Data

Address and Employment Data, MSHA

Address and Employment data are submitted to Mine Safety and Health Administration (MSHA) by mine operators on a quarterly basis. Each record includes demographic data for the mine, injury summary by quarter and employment average by quarter and operation. NIOSH downloads the data quarterly from the MSHA's web site.

Miner employment figures are averages of the employment at all underground mines. These figures under-represent total employment (those every employed during the period) due to continuous turnover in the workforce during each period.

For more information: U.S. Department of Labor, Mine Safety and Health Administration, Information Technology Center, P.O. Box 25367, Denver, CO 80225 (http://www.msha.gov/STATS/PART50/p50y2k/p50y2k.htm)

Black Lung Benefit Awards, SSA and DOL

Title IV of the Coal Mine Health and Safety Act of 1969 authorizes a benefits program, providing medical payments and cash stipends for miners totally disabled because of pneumoconiosis arising out of employment in underground coal mining, as well as for surviving spouses of coal miners whose death resulted from the disease or who were entitled to Black Lung benefits at the time of death. The Social Security Administration (SSA) was assigned initial responsibility for operating the benefits program. The Black Lung Benefits Act of 1972 continued SSA responsibility for payments to miners granted claims before July 1973, assigned the Department of Labor (DOL) responsibility for claims filed after July 1973, and extended eligibility for benefits to surface coal miners and to surviving children of miners. This latter provision allowed children to receive benefits if both parents were deceased, or if a surviving spouse ceased to qualify for benefits through remarriage. In September 1997, in an effort to enhance customer service to Black Lung program beneficiaries, the responsibility for managing all active SSA Black Lung claims was assigned to DOL. This program change was made permanent in 2002 when the Black Lung Consolidation of Administrative Responsibility Act placed the administration of both programs with DOL.

For more information: U.S. Department of Labor, Office of Workers' Compensation Programs, 200 Constitution Avenue, NW, Washington, DC 20210; and Division of Coal Mine Workers' Compensation, or Federal Black Lung Program at http://www.dol.gov/owcp/dcmwc/index.htm.

Coal Workers' Health Surveillance Program, NIOSH

The Coal Workers' Health Surveillance Program (CWHSP), formerly known as the Coal Workers' X-Ray Surveillance Program (CWXSP), is a NIOSH-administered occupational health program initially mandated by the Coal Mine Health and Safety Act of 1969. The primary objective of the CWHSP is to screen miners for coal workers' pneumoconiosis (CWP). Since 1970, coal mine operators have been required to offer a chest radiograph to all workers at U.S. underground coal mines at the time of hire and again three years later. Subsequently, miners are offered radiographs at approximately five-year intervals. The examinations are done at no cost to the miners. In addition to the posterior-anterior chest x-ray, other information is collected, including miner identification, age, tenure, and specific job in the mine. Beginning in September 2005, NIOSH, in collaboration with the Mine Safety and Health Administration (MSHA), initiated an outreach component for the CWHSP, labeled the Enhanced Coal Workers' Health Surveillance Program (ECWHSP). The ECWHSP uses a mobile examination unit to provide chest x-ray examinations at easily accessible locations.

The chest radiographs are read by physicians who have demonstrated proficiency to NIOSH in the use of the International Labour Office (ILO) system for classifying radiographs of the pneumoconioses. Each chest image is read by at least two readers, and a consensus rule is used to reach a final determination. The CWHSP defines radiographic evidence of CWP as a final determination of small opacity profusion category of at least 1/0 or large opacities (i.e., larger than one centimeter in diameter). Any miner with CWP on his/her chest radiograph is offered the option to work in an area of the mine with a respirable coal mine dust level of 1 mg/m3 or less and have personal dust exposures monitored at frequent intervals.

The large numbers of chest x-ray examinations since 1970 provide a means of monitoring the prevalence of CWP among active coal miners at underground mines. Due to selective participation, the reported tenure-specific prevalence estimates may not be representative of the entire underground coal mine work force. Also, overall crude prevalence estimates may reflect over-representation of newly employed miners. Current tabulations of CWHSP data may vary from those presented in earlier tables and figures (see Archives) due to revised criteria for categorizing tenure and time periods.

For more information: Coal Workers' Health Surveillance Program, Surveillance Branch, Division of Respiratory Disease Studies, NIOSH, 1095 Willowdale Road, Morgantown, WV 26505 (http://www.cdc.gov/niosh/topics/surveillance/ORDS/CoalWorkersHealthSurvProgram.html).

Integrated Management Information System, OSHA

The Integrated Management Information System (IMIS) includes most of the industrial hygiene sample data from Occupational Safety and Health Administration (OSHA) compliance inspections and consultation surveys conducted since May 1979. The data are reported by OSHA compliance safety and health officers and OSHA state consultants. Each IMIS record includes sample date, substance code, airborne concentration, sample type and exposure type, occupation, OSHA permissible exposure limit (PEL), and Standard Industrial Classification codes. IMIS information is entered as events occur in the course of agency activities. Until cases are closed, IMIS entries concerning specific OSHA inspections are subject to continuing correction and updating. Therefore, numbers of samples reported for a given year, or period of years, may differ from those previously reported. NIOSH receives the data yearly from OSHA's IMIS Database.

For more information: U.S. Department of Labor, Occupational Safety and Health Administration, Directorate of Information Technology, 200 Constitution Avenue, NW, Washington, DC 20210 (http://www.osha.gov/index.html).

Metal/Nonmetal Mine Data, MSHA

The metal/nonmetal mine data (MNMD) are records of industrial hygiene samples collected by Mine Safety and Health Administration (MSHA) inspectors in non-coal surface and underground mines and mills since 1974. Each personal MNMD sample record includes sample date, contaminant code, airborne concentration, occupation, MSHA permissible exposure limit (PEL), percent silica and silica concentration where available, standard industrial classification, and the mine and/or mill at which the sample was obtained. In 1982, Congress temporarily removed the surface stone, and sand and gravel industries from MSHA's jurisdiction. During this year the number of respirable dust samples collected is fewer than in other years. The quartz reference standard used for MNMD samples changed in 1988. As a result, the reported percent quartz content, quartz concentrations, and the percentage of samples exceeding the PEL increased in 1988 from 1987. MSHA occasionally revises and updates MNMD files, so the number of records reported for a given year, or period of years, may differ from those previously reported.

NIOSH receives the data yearly from MSHA's TeraData Query System. It should be noted that MSHA changed the procedures used for entering data into the TeraData Query System from field entry with little or no quality assurance checks to computerized input from the Laboratory Information Management System (LIMS) with built-in quality assurance checks to minimize or eliminate data or coding errors. In short, it appears that MSHA's asbestos data in their preamble and final rule conflicts with the MSHA asbestos data reported by NIOSH because of the data or coding errors existing in TeraData.

For more information: U.S. Department of Labor, Mine Safety and Health Administration, Metal and Nonmetal Mine Safety and Health, Health Division, 1100 Wilson Boulevard, Arlington, VA 22209 (http://www.msha.gov/programs/metal.htm).

For more information on the quartz reference standard used for the MNMD samples: Mine Safety and Health Administration, Pittsburgh Safety and Health Technology Center, Dust Division, P.O. Box 18233, Pittsburgh, PA 15236 (http://www.msha.gov/techsupp/pshtcweb/dust.htm).

Multiple Cause-of-Death Data, NCHS

The National Center for Health Statistics (NCHS) has made available annual public-use multiple cause-of-death data files since 1968. These files contain records of all deaths in the United States (approximately two million annually) that are reported to state vital statistics offices. Each death record includes codes for up to 20 (14 for ICDA-8 data) conditions listed on the death certificate, including both underlying and contributing causes of death in two fields: the entity axis, which preserves diagnostic detail for all listed conditions and their placement on the death certificate; and the record axis, which reorders the codes, removes redundancies, and (infrequently) combines some associated conditions (see Detail Record Layout at http://www.cdc.gov/nchs/nvss/mcd/1998mcd.htm). Other data include age, race, sex, and state and county of residence at time of death. In addition, usual industry and occupation codes are available for decedents from some states, for certain years during 1985–1999 (see States (and Years) for which Industry and Occupation Codes from Death Certificates Met NCHS Quality Criteria, 1985–1999).

Potential limitations of multiple cause-of-death data include: under- or over-reporting of conditions on the death certificate by certifying physicians; incomplete or no reporting of usual industry and occupation; and non-specificity of some industry and occupation codes.

For more information: Centers for Disease Control and Prevention, National Center for Health Statistics, National Vital Statistics System, 3311 Toledo Road, Hyattsville, MD 20782 (http://www.cdc.gov/nchs/deaths.htm); National Center for Health Statistics, National Vital Statistics System publications and reports at (http://www.cdc.gov/nchs/nvss/mortality_products.htm); and Centers for Disease Control and Prevention WONDER at (http://wonder.cdc.gov/).

For more information on usual industry and occupation codes see Technical Appendices for 1995 and 1999 at http://www.cdc.gov/nchs/products/vsus.htm#appendices.

The National Occupational Respiratory Mortality System (NORMS), available at http://webappa.cdc.gov/ords/norms.html, is a data-storage and interactive data-retrieval system developed and maintained by NIOSH. The system contains national census data and national mortality data obtained annually (since 1968, unless otherwise indicated) from the NCHS multiple cause-of-death data files. For the pneumoconioses, malignant mesothelioma, and hypersensitivity pneumonitis, NORMS offers a range of search options for generating tables, charts, and maps of the number of deaths, crude death rates, age-adjusted death rates, and years of potential life lost at national, regional, state, and county levels for U.S. residents by age, race, sex, and Hispanic origin. For all of the respiratory conditions listed in the International Classification of Diseases (ICD) Codes, NORMS users can tabulate deaths, years of potential life lost, and proportionate mortality ratios by usual industry and/or occupation for a subset of states and years (see States (and Years) for which Industry and Occupation Codes from Death Certificates Met NCHS Quality Criteria, 1985–1999).

National Health Interview Survey, NCHS

The National Health Interview Survey (NHIS) is a multi-purpose health survey conducted by the National Center for Health Statistics (NCHS) since 1957. It provides information on the health of the civilian, non-institutionalized population of the United States. NHIS data are collected annually through a personal household interview from approximately 40,000 households and include about 100,000 persons. The households selected for interview in the NHIS are a probability sample representative of the target population. The annual response rate of the NHIS is near 90% of the eligible households in the sample. The sample adult (18 years and older) data were used for analysis.

For more information: National Center for Health Statistics, Division of Health Interview Statistics, 3311 Toledo Road, Hyattsville, MD 20782 (http://www.cdc.gov/nchs/nhis.htm).

National Hospital Discharge Survey, NCHS

The National Hospital Discharge Survey (NHDS), conducted yearly by the National Center for Health Statistics (NCHS) since 1965, collects information on characteristics of inpatients discharged from non-Federal short-stay hospitals in the United States. Federal, military, and Department of Veterans Affairs hospitals are excluded. Only hospitals with six or more beds for patient use and those in which the average length of stay for all patients is less than 30 days are included.

From 1965–1987 the same sample design was implemented and a redesign of the survey occurred in 1988. From 1988–2007 the survey collected data from a sample of approximately 270,000 inpatient records from about 500 hospitals. Beginning in 2008 the sample size was reduced to 239 hospitals. Each discharge record includes information on patient age, race, sex, ethnicity (since 1985), marital status, length of stay, source of payment (since 1977), diagnoses (principal and other diagnosis coded to the International Classification of Diseases, 9th Revision, Clinical Modification) and surgical procedures, hospital size, ownership, and region of the United States.

One limitation of NHDS data is that they represent number of discharges, not number of patients. In addition, information on the number of hospital discharges is available only nationally and by region, but not by state. The NHDS relies on the completeness of hospital medical records, and findings can be influenced by diagnostic practices.

For more information: National Center for Health Statistics, Hospital Care Team Ambulatory and Hospital Care Statistics Branch, 3311 Toledo Road, Hyattsville, MD 20782 (http://www.cdc.gov/nchs/nhds.htm).

Occupational and Environmental Disease Surveillance Database Case Reports, AOEC

The Association of Occupational and Environmental Clinics (AOEC) has maintained a database for occupational and environmental diseases and chronic injuries since 1991. Data summarized and supplied by AOEC in three reports for 1994–1996, 1997–2000, and 2001–2004 were used. The summary reports provide descriptions of cases with diagnoses associated with occupational exposures other than asbestos, asbestos exposures, and environmental exposures. AOEC defines a case as one that must have at least one diagnosed condition that, in the physician's judgment, is more likely than not to be related to occupational or environmental exposures. A case can have up to three diagnosed conditions and each condition can have up to three hazards or exposures.

Sixteen AOEC member clinics contributed cases for the period 1994–2004; 4,720 cases had diagnoses associated with asbestos exposure and 5,280 cases had diagnoses associated with occupational exposures other than asbestos. Five clinics participated in at least nine years of the 11-year period and contributed 85% of the cases. Four other clinics contributed over 150 cases each (13% of all cases). While not necessarily representative of all patients with work-related conditions, these case reports provide insight into the types of occupational conditions being treated by occupational medicine specialists, as well as into the types of exposures that are causing or exacerbating these diseases.

For more information: Association of Occupational and Environmental Clinics, 1010 Vermont Avenue, NW, #513, Washington, DC 20005 (http://www.aoec.org).

Population Data Estimates, BoC and CDC

National population estimates are based on national, state, and county-level data from the Bureau of the Census (BoC). All population estimates used to compute death rates for 1968–1999 have been obtained through the Centers for Disease Control and Prevention (CDC) computer system. Estimates obtained from unmodified intercensal Demo-Detail files were used for 1970–1979 (http://wonder.cdc.gov/wonder/sci_data/census/inter/type_txt/inter708.asp) and for 1980–1989 (http://wonder.cdc.gov/wonder/sci_data/census/inter/type_txt/y8090bur.asp). The unmodified 1970 intercensal population estimates were used for 1968–1969 because no other county-level population estimates were available. Postcensal Demo-Detail estimates (http://wonder.cdc.gov/wonder/sci_data/census/post/type_txt/demo95.asp) were used for 1990–1995. Comparable postcensal estimates prepared by the BoC (http://wonder.cdc.gov/wonder/sci_data/census/post/type_txt/cen9097.asp) were used for 1996–1999. Since 2000, National Center for Health Statistics bridged-race estimates (http://www.cdc.gov/nchs/nvss/bridged_race.htm) have been used. [Note: Comparison of population statistics from Demo-Detail and BoC postcensal estimates for each year from 1990 through 1995 showed that there was a maximum annual difference of less than 0.05 percent, and a difference of 0.01 percent or less in a majority of years. State-specific differences for the same years were less than one percent for individual states, with very rare exceptions.] For more information about the 1990 U.S. Census and 2000 U.S. Census see U.S. Census Bureau at http://www.census.gov/main/www/cen1990.html and http://www.census.gov/main/www/cen2000.html.

For more information on population estimates see http://www.census.gov/popest/estimates.html.

Respirable Coal Mine Dust Data, MSHA

Respirable coal mine dust measurements were collected by Mine Safety and Health Administration (MSHA) inspectors and mine operators at surface and underground coal mines and facilities since 1970. Each record includes sample date, duration, and airborne concentration, as well as occupation and the mine or facility at which the sample was obtained. NIOSH receives the data yearly from MSHA's Laboratory Information Management System (LIMS) Database.

For more information: U.S. Department of Labor, Mine Safety and Health Administration, Information Technology Center, P.O. Box 25367, Denver, CO 80225 (http://www.msha.gov/CONTACTS/PEIRNOS.HTM).

For more information on the Coal Mine Health Inspection Procedures PH89-V-1(21): U.S. Department of Labor, Mine Safety and Health Administration, Coal Mine Safety and Health, 1100 Wilson Boulevard, Arlington, VA 22209 (http://www.msha.gov/READROOM/HANDBOOK/HANDBOOK.HTM).

Respirable Coal Mine Quartz Dust Data, MSHA

Respirable quartz measurements were collected by Mine Safety and Health Administration (MSHA) inspectors and mine operators at surface and underground coal mines and facilities since 1982. Each record includes sample date, duration, percent quartz, and airborne concentration, as well as occupation and the mine or facility at which the sample was obtained. NIOSH receives the data yearly from MSHA's Pittsburgh Quartz Database.

For more information: Mine Safety and Health Administration, Pittsburgh Safety and Health Technology Center, Dust Division, P.O. Box 18233, Pittsburgh, PA 15236 (http://www.msha.gov/techsupp/pshtcweb/dust.htm).

For more information on the Coal Mine Health Inspection Procedures PH89-V-1(21): U.S. Department of Labor, Mine Safety and Health Administration, Coal Mine Safety and Health, 1100 Wilson Boulevard, Arlington, VA 22209 (http://www.msha.gov/READROOM/HANDBOOK/HANDBOOK.HTM).

State-Based Surveillance Case Data, NIOSH

In 1987, NIOSH began funding the Sentinel Event Notification Systems for Occupational Risks (SENSOR) program and awarded cooperative agreements to various state health departments and other state entities to develop models for state-based and condition-specific sentinel surveillance and preventive intervention. Two of the conditions for which states were funded through this program are silicosis and work-related asthma (WRA). In 2002, funding for the program known as SENSOR ended, though state entities continue to employ the sentinel surveillance model and many still use the term "SENSOR" as applied to their state program. The funded program is currently referenced as the State-Based Surveillance (SBS) program: the SBS program consists of the Fundamental Program and the Expanded Program with the Expanded Program most closely mirroring the program formerly known as SENSOR. For more information about the state-based surveillance program for silicosis and work-related asthma see http://www.cdc.gov/niosh/topics/surveillance/ords/StateBasedSurveillance.html.

For silicosis, Michigan and New Jersey have maintained a silicosis surveillance program since 1988 and provide data to NIOSH. Ohio maintained a NIOSH-funded silicosis surveillance program from 1988–2002 under the former SENSOR program and provided data to NIOSH during the funding period. All three states used similar methods to identify potential cases using a variety of sources: review of state death certificate data, case reports from physicians, and review of hospital discharge data or direct hospital reporting to the state health department. In addition, Michigan and Ohio review workers' compensation records. In all three states, demographic, work history, and medical information used for case confirmation and description was obtained through a combination of case report review from the initial case ascertainment source, review of medical records, and follow-up telephone interview with the reported cases or their surviving next-of-kin.

California maintained a NIOSH-funded silicosis surveillance program from 2000–2002, and data for these three years have been provided to NIOSH. California identified potential cases by reviewing data from Doctor's First Report (DFR) of Occupational Injury or Illness, a longstanding statewide physician reporting system linked to physician reimbursement for medical services, as well as data sources mentioned above. Demographic, work history, and medical information used for case confirmation and description was obtained through a combination of case report review from the initial case ascertainment source, review of medical records, and follow-up telephone interview with the reported cases or their surviving next-of-kin.

For surveillance purposes, silicosis case confirmation requires a history of occupational exposure to airborne silica dust and either or both of the following: (a) a chest radiograph or other imaging technique interpreted as consistent with silicosis and/or (b) lung histopathology characteristic of silicosis (see Silicosis State Reporting Guidelines).

For more information on the State-Based Silicosis Program see NIOSH, Occupational Respiratory Disease Surveillance Topic Page, State-Based Surveillance at http://www.cdc.gov/niosh/topics/surveillance/ords/StateBasedSurveillance/Silicosis.html.

For work-related asthma (WRA), Massachusetts, Michigan, and New Jersey have maintained WRA surveillance programs since 1988, and California since 1993. All four states provide data to NIOSH. Physician case reports remain the primary ascertainment source in these four states; however, they have gradually increased the number of data sources for ascertainment of potential cases of WRA. Massachusetts, Michigan, and New Jersey actively solicit physicians for case reports, whereas California identifies potential cases by reviewing data from DFR of Occupational Injury or Illness. All four states solicit and review hospital discharge data for potential WRA cases and each state obtains workers’ compensation data from their state workers’ compensation systems. In 2002, Michigan began to supplement case ascertainment with review of state poison control data.

State surveillance staff collected demographic data, work history, and medical information for surveillance case confirmation, classification, and description purposes through a combination of the initial case ascertainment source, a review of medical records, and follow-up telephone interview with reported cases. WRA case confirmation requires a healthcare professional's diagnosis of asthma (or a related diagnosis consistent with asthma) and an association between symptoms of asthma and workplace exposures or conditions. Confirmed WRA cases are classified according to established criteria (see Work-Related Asthma State Reporting Guidelines). To facilitate consistency in agent coding across states, putative causes of WRA are coded using the Association of Occupational and Environmental Clinics (AOEC) exposure coding scheme (http://www.aoec.org/tools.htm), which flags "known asthma inducers".

For more information on the State-Based Work-Related Asthma Program see NIOSH, Occupational Respiratory Disease Surveillance Topic Page, State-Based Surveillance, Work-Related Asthma at http://www.cdc.gov/niosh/topics/surveillance/ords/StateBasedSurveillance/wra.html.

Survey of Occupational Injuries and Illnesses, BLS

After passage of the Occupational Safety and Health Act of 1970, the responsibility for collecting statistics on occupational injuries and illnesses was delegated to the Bureau of Labor Statistics (BLS). The BLS Survey of Occupational Injuries and Illnesses, done in cooperation with participating state agencies, involves data collection by mail from a sample of private industry establishments each calendar year. Nearly all industries in the private sector (employers covered by the Occupational Safety and Health Act of 1970) are included. Annual BLS reports of these data incorporate corresponding data from mine operators, provided to BLS by the Mine Safety and Health Administration (MSHA), and from railroad transportation employers, provided to BLS by the Federal Railroad Administration. National estimates of injury and illness incidence rates by industry are developed from the survey data. Beginning in 1992, the survey was expanded to provide more information on illnesses resulting in days away from work, allowing for more detailed classification of respiratory system diseases. The BLS reports the number and incidence rates of work-related injuries and illnesses in private industry for each year. Annual summary data on respiratory illnesses were abstracted from BLS annual reports on occupational injuries and illnesses for eWoRLD.

In contrast with injury data, illness data presented in the BLS annual reports are quite limited because employers typically do not recognize and report illnesses, particularly illnesses with a long latency. Also, the survey does not cover all workers since it excludes the self-employed; farm operators with fewer than 11 employees; private households; public sector employees; and independent mining contractors. Since 2008, BLS includes state and local government agencies in the survey.

Since 2003, BLS has classified industry according to the 2002 North American Industry Classification System (NAICS). BLS stopped reporting "dust diseases of the lungs" and "respiratory conditions due to toxic agents" after 2001. Since 2002, BLS combined these conditions and reported them as a new category called "respiratory conditions". BLS defined these conditions as follows: "Dust diseases of the lungs" (pneumoconioses) includes silicosis, asbestosis, coal workers' pneumoconiosis, byssinosis, siderosis, and other pneumoconioses; "Respiratory condition due to toxic agents" includes pneumonitis, pharyngitis, rhinitis or acute congestions due to chemicals, dusts, gases or fumes; "Respiratory conditions" includes silicosis, asbestosis, pneumonitis, pharyngitis, farmer's lung, beryllium disease, tuberculosis, occupational asthma, reactive airways dysfunction syndrome (RADS), chronic obstructive pulmonary disease (COPD), hypersensitivity pneumonitis, rhinitis or acute congestions due to chemicals, dusts, gases or fumes, siderosis, pneumonia, influenza, toxic inhalation injury such as metal fume fever, chronic obstructive bronchitis, other pneumoconioses, and other respiratory system diseases.

For more information: U.S. Department of Labor, Bureau of Labor Statistics, Office of Safety, Health and Working Conditions, Postal Square Building - Suite 3180, 2 Massachusetts Avenue, NE, Washington, DC 20212; http://www.bls.gov/iif/home.htm; and annual reports: Occupational Injuries and Illnesses: Counts, Rates, and Characteristics at http://www.bls.gov/iif/publications.htm.

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