Worker Health Chartbook 2004

Centers for Disease Control and Prevention (CDC): The Centers for Disease Control and Prevention (CDC) is headquartered in Atlanta, Georgia, and is an agency of the U.S. Department of Health and Human Services. CDC is recognized as the lead Federal agency for protecting the safety and health of people at home and abroad. CDC provides credible information to enhance health decisions and promote health through strong partnerships with other public and nongovernment organizations. CDC serves as the national focus for developing and applying disease prevention and control, occupational and environmental health, and health promotion and education activities designed to improve the health of the people of the United States.

Civilian labor force: The civilian labor force comprises all civilians classified as employed and unemployed.

Employed persons: Employed persons are all persons who fit into one of the following categories during the reference week of the U.S. Census Bureau’s Current Population Survey: (1) persons who did any work at all as paid employees, worked in their own business or profession or on their own farm, or worked 15 or more hours as unpaid workers in a family-operated enterprise; and (2) all persons who did not work but had jobs or businesses from which they were temporarily absent because of illness, bad weather, vacation, child-care problems, labor disputes, maternity or paternity leave, or other family or personal obligations—whether or not they were paid by their employers for the time off and whether or not they were seeking other jobs.

Fatal occupational injury rate: Fatal occupational injury rates are determined by combining the number of fatal occupational injuries identified by the Census of Fatal Occupational Injuries (CFOI) with the average annual number of employed workers from the Current Population Survey (CPS). These rates depict the risk that certain workers (such as those in a given occupation or industry) have of incurring a fatal injury. The formula for calculating a fatal occupational injury rate is

Fatal injury = (N/W) × 100,000

where N = the number of fatally injured workers aged 16 and older and W = the number of employed workers aged 16 and older.

For example, in computing the fatal occupational injury rate for 1994,

N = 6,588 – 25 workers under age 16

= 6,563 (from 1994 CFOI)

and

W = 124,469,000

(from Current Population Survey 1994 annual average plus resident military figures derived from Census Bureau data). Thus

Fatality rate = (6,563/124,469,000) × 100,000

= 5 deaths per 100,000 workers

Because neither hours nor employment figures are collected in the Bureau of Labor Statistics (BLS) census (CFOI), fatality rates are calculated using annual average employment estimates from the Current Population Survey, conducted for BLS by the Census Bureau. Employment-based fatality rates measure the incidence of a fatal injury for all workers in the group regardless of exposure time. Such measures do not reflect the movement of persons into and out of the labor force, the length of their workweek or work year, or the effect of multiple jobholders.

Hispanic workers: Hispanic workers are those who trace their origins to a Spanish-speaking country or culture. Origins may include the heritage, nationality group, ancestry, or country of birth of the person or person’s parents or ancestors. People who identify their origin as Hispanic may be of any race.

Incidence rate for nonfatal injury or illness: Incidence rates for nonfatal injury or illness are calculated using the total obtained through the weighting and benchmarking procedures. The adjusted estimates for a particular characteristic (for example, for injury and illness cases involving days away from work) are aggregated to the appropriate level of industry detail. The total is multiplied by 200,000 (the base of hours worked by 100 full-time workers for 1 year). The product is then divided by the weighted and benchmarked estimate of hours worked as reported in the survey for a particular industry segment.

The formula for calculating the incidence rate at the lowest level of industry detail is

Incidence rates for higher levels of industry detail are produced using aggregated, weighted and benchmarked totals. Rates may be computed by industry, employment size, geographic area, extent or outcome of case, and case characteristic category. Rates for illnesses and rates for case characteristic categories are published per 10,000 full-time employees using 20 million hours instead of 200,000 hours in the above formula. Rates per 10,000 workers can be converted to rates per 100 workers by moving the decimal point two places to the left and rounding the resulting rate to the nearest tenth.

Industry: An industry consists of a group of establishments primarily engaged in producing or handling the same product or group of products or in rendering the same service or services. For more than 60 years, the Standard Industrial Classification (SIC) system has served as the structure for the collecting, aggregating, presenting, and analyzing data on the U.S. economy. Industry definitions used in BLS programs come from the 1987 Standard Industrial Classification (SIC) Manual of the Office of Management and Budget. Because the SIC is used by many other Federal government statistical programs, it is possible for users to assemble a comprehensive statistical picture of an industry.

Lost-workday cases: Lost-workday cases are cases of nonfatal injury or illness that involve days away from work, or days of restricted work activity, or both.

Lost-workday cases involving days away from work: Lost-workday cases are cases that result in days away from work or a combination of days away from work and days of restricted work activity.

Lost-workday cases involving restricted work activity: Lost-workday cases involving restricted work activity are those cases that result in restricted work activity only.

Median: A median is a measure of central tendency: it constitutes the middle value in a distribution. The simplest division of a set of measurements is into two parts—the lower and the upper half. The point on the scale that divides the group in this way is the median. Median days away from work is the measure used in many Chartbook figures to summarize the varying lengths of absences from work among the cases with days away from work.

Noise-induced hearing loss: Noise-induced hearing loss refers to a sensorineural hearing loss caused by repeated exposure to high-intensity sound levels. Noise-induced hearing loss is characterized by irreversible damage to the sensory hair cells located in the inner ear. The condition is usually preventable by limiting noise exposures or by using personal hearing protection devices.

Occupation: Occupation is a set of activities or tasks that workers are paid to perform. Workers that perform essentially the same tasks are in the same occupation whether or not they are in the same industry. Some occupations are concentrated in a few industries, and others may be found in the majority of industries.

Current, recent, or usual job activity information is collected by many agencies to help characterize an occupation. Questions are used to obtain information about the kind of work and the most important activities or duties. This information, in conjunction with industry or employer and class of worker (e.g., private or public sector, nonprofit, self-employed), is used to classify jobs by occupational class. BLS data on the occupation of the injured or ill worker was coded from job titles supplied by the employer, supplemented at times by employer descriptions of how the incident occurred.

The 1990 Occupational Classification System developed by the Census Bureau was used to classify thousands of job titles supplied by employers into several hundred individual occupations such as registered nurse, licensed practical nurse, or nursing aide or orderly. Each occupation is tied to one of six major occupational groups: (1) managerial and professional specialty, (2) technical, sales, and administrative support, (3) service occupations, (4) farming, forestry, and fishing, (5) precision production, craft, and repair; and (3) operators, fabricators, and laborers.

Occupational injury: An occupational injury is any injury such as a cut, fracture, sprain, amputation, etc. that results from a work-related event or from a single instantaneous exposure in the work environment.

Occupational illness: An occupational illness is any abnormal condition or disorder (other than one resulting from an occupational injury) caused by exposure to factors associated with employment. Occupational illness includes acute and chronic illnesses and diseases that may be caused by inhalation, absorption, ingestion, or direct contact.

Proportionate mortality ratio (PMR): The proportionate mortality ratio (PMR) is defined as the observed number of deaths with the condition of interest (mentioned as either underlying or contributing) in an industry/occupation from selected States and years, divided by the expected number of deaths with that condition. The expected number of deaths is the total number of deaths in the industry or occupation classification of interest multiplied by a proportion. This proportion is defined as the number of cause-specific deaths for the condition of interest in all industries/occupations divided by the total number of deaths in all industries/occupations. The PMRs in this report have been internally adjusted by 5-year age groups (i.e., 15–19, 20–24, . . . , 110–114, and 115 years and over), sex, and race (i.e., white, black, and all other). Confidence intervals were calculated assuming Poisson distribution of the data. A PMR greater than 1.0 indicates that more deaths were associated with the condition in an occupation or industry than expected. This report includes only those industries/occupations with 5 or more decedents with the condition and a lower 95% confidence limit exceeding 1.0.

Race: Race refers to a human population distinguished as a group by certain physical characteristics. However, the concept of race involves self-identification. Racial categories are sociopolitical constructs and should not be interpreted as being scientific or anthropological. Racial categories include both racial and national-origin groups. The racial classifications used by most Federal agencies since 1997 follow the standards set forth in the October 30, 1997, Federal Register Notice entitled Revisions to the Standard Classification of Federal Data on Race and Ethnicity. The Office of Management and Budget (OMB) requires five minimum categories for race: white; black or African American; American Indian or Alaska Native; Asian; and Native Hawaiian or other Pacific Islander. OMB also states that respondents should be offered the option to select one or more races.

Reader: Reader is a designation granted by NIOSH to physicians who demonstrate proficiency in classifying chest X-rays for the pneumoconioses using the International Labour Office (ILO) Classification system. NIOSH has established a two-tier system for designating readers: A Readers have completed a training course or have otherwise demonstrated competence in the use of the ILO Classification; B Readers have successfully completed a certification examination and must be recertified every 4 years. A final determination about the classification of each X-ray requires agreement between at least two Readers, one of whom must be a B Reader.

Rates: See incidence rates or fatal occupational injury rates.

Sentinel Event Notification System for Occupational Risk (SENSOR): The Sensor program is a NIOSH cooperative agreement program with State health departments or other State agencies that develops generalizable, condition-specific strategies for State-based surveillance of occupational diseases and injuries. Efforts have focused on standardization of variables collected by the State programs, creation of software to facilitate adoption of the surveillance systems by additional States, comparison of SENSOR findings to other surveillance data sources, collaboration with the Council of State and Territorial Epidemiologists (CSTE) on building infrastructure for State-based surveillance, further development of State-based hazard surveillance, and publication and dissemination of SENSOR reports.

Severity: Severity of an injury or illness is estimated by using information provided by employers about the number of days away from work to recuperate from each disabling condition. If, as a result of injury or illness, the worker did not return to work by the end of the survey year, the employer reports an approximate return date that, in conjunction with the date of injury or illness, yields an estimated number of days away from work for that case. Two basic measures of severity are used with the characteristics of days-away-from-work cases: (1) median days away from work (the point at which half of the days-away-from-work cases have a longer duration and half have a shorter duration; and (2) the distribution of days-away-from-work cases involving various lengths of absences from work, ranging from 1 or 2 days to 31 days or longer.

Surveillance: Surveillance is the systematic, ongoing collection or acquisition of information about occupational diseases, injuries, and hazards. Surveillance includes the analysis and interpretation of surveillance data, the dissemination of data or information derived from surveillance to appropriate audiences for prevention and control, and the development of surveillance methodology.

Abbreviations

Acknowledgments