Work-related fatal injuries in older California workers, 1979–1985

Journal of Occupational Elsevier

Accidents,

12 (1990)

223

223-235

Work-Related Fatal Injuries in Older California Workers, 1979-1985” JESS

F. KRAUS,

JUDITH

MACURDA,

JACK

SAHL

Department of Epidemiology and UCLA Occupational Los Angles, CA 90024-l 772, U.S.A.

and CRAIG

ANDERSON

Health Center,

University

of California,

ABSTRACT Kraus, J., Macurda, fornia workers, Accurate

J., Sahl, J. and Anderson,

1979-1985.

information

Journal of

C., 1990. Work-related

fatal injuries

in older Cali-

Occupational Accidents, 12: 223-235.

on those injured while at work depends

on the quality

of the reporting

mechanisms in place. There is ample evidence that such reporting mechanisms in the United States are flawed, and injuries to some segments of the work force may be grossly underenumerated. This research reports on a new system to identify, more accurately, work-related fatal injuries with particular reference to those past normal retirement age. The system relies on the death certificate and involves a computer search of data fields possibly indicative of a work association. In addition, the actual certificate is examined, and when necessary, the coroner’s record is obtained to clarify the work-related connection. From 1979 through 1985,195 deaths were confirmedas work-related, all but ten among working males. The rate in males was ten times higher than for females. Homicide was the most frequent external cause of death. Rates were highest in mining, agriculture, transportation, communication and utilities, and business services, cooks, bartenders, farmers, drivers, and security guards. Fortysix percent of the deaths occurred among self-employed persons.

INTRODUCTION

Information on the association of occupation and industry with the occurrence of fatal and nonfatal work-related injuries has importance for etiological research, planning for injury-prevention countermeasures, and occupational health surveillance to describe workplace hazards (Baker et al., 1989). The accurate identification and epidemiologic description of those who are injured while at work depends on the quality of the reporting mechanisms in place. Pollack and Keiming (1987), reporting for the Panel on Occupational Safety and Health Statistics of the United States National Research Council, *Presented Stockholm,

at the International Conference on Strategies Sweden, 21-22 September 1989.

0376-6349/90/$03.50

0 1990-Elsevier

Science

Publishers

for Occupational

B.V.

Accident

Prevention,

224

concluded that the U.S. Bureau of Labor Statistics (BLS, 1987) data systems were inadequate for providing the U.S. Occupational Safety and Health Administration (OSHA) with the data it needs for maintaining an effective program for prevention of workplace injuries and illnesses. For example, the injury report from the BLS for 1985 depended entirely on an annual survey which, in turn, depends on the timeliness and completeness of responses from a sample of about 280,000 private-sector employers. Intentional failure to report illness or injuries in some industries, as well as the exclusion of the selfemployed, establishments with fewer than 11 employees, state, federal, and local government agencies, and establishments regulated by other federal safety and health laws diminishes the value of the survey results to portray the injuries among the working population of the country. Even if the annual BLS survey was designed to be representative of all industries and occupations, the data collected are limited in that details of the incident, individual factors such as work experience or exposure description, and nature of the injury are not recorded or reported (Hanrahan and Moll, 1989). The U.S. National Institute of Occupational Safety and Health, Division of Safety Research, has developed a system called the National Traumatic Occupational Fatality system (NTOF) to partially overcome the shortcomings in the BLS data system by using the death certificate as the data source for fatal injuries (Division of Safety Research, 1989). Problems remain, nonetheless, with the ability to accurately identify those deaths which are truly workrelated because those responsible for completing the certificate lack standards, guidelines, or even definitions to apply in filling out the document with respect to the relationship of the fatal injury to a work exposure. The injury reporting exceptions in OSHA (and the BLS) mentioned above are not a difficulty in the NTOF system because almost all deaths in the United States are reported. Of concern, however, are differences in reporting practices by state or local agencies which affect the amount or type of information recorded on the death certificate. For example, fatal injuries to persons under the age of 16 might not be related to work exposures because occupation and industry for the decedent might be routinely recorded as “student” and “education,” respectively, regardless of the actual circumstances of death. Self-inflicted injuries likewise might not be relatable to work exposures because of the difficulty in establishing the validity of such an association. Fatal workrelated injuries to persons past normal retirement age may also be overlooked because of uncertainty regarding membership in the work force (Harrison and Frommer, 1986) or the common practice of designating “retired” in the “occupation” field on the death certificate. PURPOSE

This research has two specific purposes: to report on a newly developed system to more accurately identify work-related fatal injuries in a defined work-

225

force and to describe, epidemiologically, work-related deaths among those past common retirement age, i.e., 65 years of age and older. METHODS

Case definition The definition of a work-related fatal injury for this research was conceptual, namely, a fatal injury to a worker resulting from activities related to compensatable work. This broad definition does not restrict the work-related activity to any specific location or place, to any type of employer, or to any time of exposure to hazard. (This latter factor is important for some workers who, at times, are “on duty” 24 hours a day.) Time from injury to death has not been specified because it is subject to local practices of medical examiner/ coroner jurisdictions following injury. For example, some deaths occur months or years postinjury and become difficult to link to an injury per se much less to a work-connected exposure. The definition does preclude (1) nonworking bystanders killed as a result of the action of workers such as persons being struck by falling beams from building construction sites, (2) self-inflicted injury because the association with a work-related exposure is difficult to establish and lacks accepted standards or criteria, (3) those dying from external causes that are not strictly traumatic injuries such as therapeutic misadventures, and (4) deaths resulting from illegal activities which, in some quarters, may be viewed as work-related such as prostitution or illegal drug sales. Case-finding To carry out the objectives of this research, it was necessary to develop a system of case-finding which did not rely on OSHA reports, workers’ compensation records, or survey data from the BLS. The system developed relied on death certificate information found in the California Master Mortality File (California Department of Health Services, 1987), a computerized system which includes selected certificate information on deaths to residents, regardless of place of death, as well as nonresidents dying in California. The steps in the process of case-finding are seen in Figs. 1 and 2. All injury deaths with an International Classification of Disease (9th Revision, Clinical Modification) External-cause codes 800-999 for California residents aged 65 years or older were computer-identified (Commission of Professional and Hospital Activities, 1987 ). Deaths from iatrogenic causes (EGO-858)) therapeutic misadventures (E870-879 or E930-949)) or operations of war (E990-999) were excluded. Next, three data fields routinely completed by California medical examiners were examined sequentially to identify further those cases that might be work-

226 STEP 1 Caiifornia f&s&r

Mortality

Fig. 1. Step 1 of case-finding 1985.

File

computer

aIgorithm for work-related

fatal injuries, California,

1979-

STEP 2 AllPossible Work-Related Cases -

Fig. 2. Steps 2 and 3 of case-finding 1979-1985.

computer

algorithm

for work-related

fatal injuries, California,

related. The three fields were: ( 1) a positive response to “injury at work”, (2 ) place of death, or (3) specific external causes listed in Table 1. If the death record was marked positive to injury at work, or occurred at a work location such as a factory or farm, or had one of the external-cause codes associated with a work-related activity such as injury to railway employees or were members of water or commercial aircraft (see Table 1)) it was considered as possibly work-related. The second step (Fig. 2 ) in case-finding involved review of the actual death certificate for evidence of work-related activity. Such information is often recorded, albeit briefly, in the section of the certificate which asks how the injury occurred. For some of the certificates, it was not clear whether the death was work-related or not, hence a final step was employed; that is, review of the coroner’s or medical examiner’s record. In California, all injury deaths are coroner cases, and the circumstances of death recorded in these reports can clarify doubtful work-related associations indicated on the death certificate.

227 TABLE

1

Possible work-related external Classification of Diseases* Rubric

cause of death codes and titles in the 9th Revision,

International

Title

800-803

(.O only)

830-838 840-845 846 848 910 918-21 923 925

(.2,.6,.8 only) (.1,.2,.5,.6,.8 only)

Railway employee Crew member in watercraft,

etc.

Crew of aircraft Power vehicle used in industry Other power vehicle Commercial diving operations Caught in machinery, pressure vessel, etc. Explosion (industrial) Electrocution (industrial)

“The International Classification of Diseases, 9th Revision, Clinical Modification, eases Tabular List, effective date, January 1, 1979.

Volume 1, Dis-

Calculation of rates

Occupation and industry, as recorded on the death certificate for each decedent, were coded using the 1980 U.S. Department of Commerce Classified Index of Occupation and Industry (U.S. Bureau of the Census, 1980-1982). U.S. census counts of the workforce over age 64 for 1980 were used to calculate rates by occupation and industry categories. Workforce enumeration for more recent years was not available. RESULTS

During the seven-year period 1979-1985, 381 possible work-related deaths were identified, and 195 of these were verified, that is, the injury which resulted in death was found to be a direct result of performance of a work-connected activity (Fig. 2). The names of all 219 deaths from 1979-1983 were crosschecked against the California OSHA log sheets which contain the names and circumstances of purported work-connected deaths. Deaths for 1984 and 1985 were not included since the log sheets may not have been complete for these years. Thirty-six of 118 deaths identified by the algorithm were also found in the official logs - an agreement of only 30.5 percent (Fig. 3). Nineteen deaths were recorded in the log sheets but were not found in the group identified by the algorithm. None of these certificates were marked “injury at work”, or an injury at work location, or had an external cause of death as listed in Table 1. The true work association of these 19 cases has not been established since many of the deaths were not injuries per se but appeared to be caused by acute events such as “heart attacks.”

228

AGREEMENT ALGORITHM vs OFFICAL LOGS (1979-1983) ALGORITHM CASE YES NO LOG SHEET CASE

TOTAL

YES

36

19

55

NO

02

l

t

116

101

TOTAL/

1 219

Agreement = 36/116 = 30.5% ‘Log sheets do not indicate negative disposition.

Fig. 3. Agreement in identification sheets, California, 1979-1983.

of fatal-injury

TABLE

2

Number 1985.

and percent of work-related

External cause Homicide Machinery or electrocutions Motor-vehicle crashes Falls Other transport Fire/flames Poisoning Submersion of suffocation All others All causes

fatal injuries among males over age 64, California,

Number of deaths 50 44 34 28 18 4 2 2 3 185

deaths computer algorithm and official state log

1979-

Percent

27.0 23.8 18.4 15.1 9.7 2.2 1.1 1.1 1.6 99.9

Type of injury. More than 42 percent of all injuries involved extensive multiple trauma. Over 24 percent died from injuries to the head, and about 10 percent died from late effects or complications of their injuries. Four percent died from spinal cord injuries, and the remainder from internal injury to thorax or abdomen, from burns, poisoning, or open wounds. External cause. The external causes of injuries are summarized in Table 2. Homicide accounted for the single largest cause (27.0% ), followed by machinery or electrocutions (23.8% ), motor-vehicle traffic crashes (18.4% ), and falls (15.1% ). About 10 percent of the deaths involved tractor overturns (other transport. )

229

Validity

All deaths identified by the algorithm were classified as “true” cases in order to evaluate the validity of the “injury at work” notion on the death certificate. The data in Table 3 shows that the notation of “injury at work”, at least with this group of deaths among older persons, has a sensitivity of about 92 percent but only a specificity of 77 percent (and a false positive rate of 23 percent). We point out, however, that we did not select a sample of death certificates with a known negative notation for “injury at work”. Overall rates Table 4 gives the number of work-related deaths, estimated annual size of the working population, and average annual rate per 100,000, by gender, over the seven-year period. The rate for males of 15 per 100,000 per year is more than ten times higher than the rate for females. Ten (5% ) of the 195 deaths were to females. Because of the small number, TABLE 3 Validity of the “Injury at Work” Designation, California Death Certificates, 1979-1985 Truth + “Injury at work”

-

Yes

179

42

No

16

140

195

186”

381

Note: Sensitivity= 179/195=91.8%, “Includes 4 unknowns.

and Specificity= 140/182=76.9%

TABLE 4 Number of deaths, size of the working population, and death rates per 100,000 working persons over age 64, California, 1979-1985. Gender

Number of deaths

Estimated working population

Death rates per 100,000

Male Female Total

185 10 195

176,767 109,074 285,841

15.0 1.3 9.7

230

the analysis which follows was restricted to males. It is noteworthy that four of the ten deaths to older working females involved a homicide. Age. Data on the age distribution of older members of the work force are not available, hence it was not possible to construct age-specific death rates. The proportions of deaths by age were: aged 6569,53%; aged 70-74,23%; aged 75 79,17%; aged 80 and older, 7%. The distribution by age of the 185 male deaths is given in Fig. 4. Industry and occupation. Industry-specific work-related death rates are given in Table 5. As expected, rates were highest in mining and agriculture industries. Elevated rates also were seen for older workers in transportation, communication, utilities industries, and business services. Table 6 gives rates of work-related-injury deaths by major occupational categories. Cooks and bartenders have the highest rates, followed by farmers, transport workers (mostly drivers), and security guards or police. Work-related fatal injuries by occupation within industry are given in Table 7. All but two of the deaths in agriculture or fisheries industries were to farmers. In the absence of data on the numbers of workers by occupation and industry, rates could not be calculated. Self-employed. Overall, 46 percent of the male deaths in older workers involved persons who were self-employed. More than 56 percent of farmers and 52 percent of those in the skilled trades were self-employed.

Age

Fig. 4. Age distribution 1985.

(years)

of work-related

fatal injuries, California workers, ages 65 and older, 1979-

231 TABLE 5 Number and average annual rate of fatal work-related injuries among males over age 64, by industry, California, 1979-1985 Industry category

Deaths

Workers

Mining Agriculture/fisheries Transportation/communication/ Utilities Business services Public administration Trade Construction Manufacturing Other Services Finance/insurance/real estate Total

Rate/lOO,OOO

15,364

5 49

105.2 45.6

7,832 13,681 6,009 37,119 9,774 26,287 41,755 18,267 176,767

22 22 7 31 7 16 17 6 185’

40.1 23.0 16.6 11.9 10.2 8.7 5.8 4.7 15.0

679

“Includes three deaths with unknown industries.

TABLE 6 Number and average annual rate of fatal work-related injuries among males over Age 64, by occupation, California, 1979-1985 Occupation category Cooks /bartenders Farmers Transport workers Police/guards Skilled trades Laborers Professional/technical Proprietors/sales Managers Clerks Service workers Total

Workers

Deaths

Rate/lOO,OOO

1,130 15,445 5,911 6,118 29,440 4,397 28,051 30,404 29,871 10,822 14,764

6 49 18 14 30 4 20 21 14 3 3

45.3 43.5 32.7 14.6 13.0 10.2 9.9 6.7 4.0 2.9

176,353

185”

15.0

“Includes three deaths with unknown occupation.

75.9

1 0 0 0 1 16 4 1 1 0 24

4 4 2 3 10 3 34

Proprietors Sales Clerks

0 1 2 5

Managers Professionals Technicians

0 1 0 7 1 3 13

0 1 0 0

Police Guards

0 6 0 1 1 0 9

0 0 0 1

Service Workers (including cooks and bartenders)

injuries among males over age 64, by industry and occupation,

“Excludes four injuries in workers with other or unknown industry or occupation.

Agriculture/fisheries Mining Construction Manufacturing Transportation/communication/ Utilities Trade Finance/insurance/real estate Business services Other services Public administration Total”

Industry

Number of fatal work-related

TABLE 7

0 0 0 0 0 1 49

47 0 0 1 2 2 0 10 1 0 30

0 3 5 7

Skilled Trades

1979-1985

Farmers/ Farm Laborers

California,

15 2 0 0 2 0 22

1 0 0 2

Transport Workers and Laborers

233 DISCUSSION

Data limitations The algorithm for finding work-related fatal injuries depends, or course, on the accuracy of the information recorded on the death certificate. Without definitions, criteria, or standards for this purpose, the death certificate will remain, at best, an approximation of the aggregate of fatal work-related injuries. In some counties in California, for example, deaths to individuals commuting to and from work are noted as work-related, whereas, in other counties, this practice is not used. The death certificate can be very useful for workrelated fatal-injury surveillance, but only if standards are developed for that purpose. Of course, it cannot provide information on nonfatal work-related injuries. Until a better system is developed, continued reliance on OSHA documents for enumeration of even fatal work-related injuries will continue to be troublesome, as pointed out in the report from the National Academy of Sciences. The importance in developing and maintaining a work-related-injury surveillance system cannot go unrecognized. A recent issue of the Supplement of the American Journal of Public Health (see Baker et al., 1989) highlights the potential data sources available, but all of these sources, even in the aggregate, have problems of uniform reporting. The entire work-injury reporting system needs to be completely reorganized and restructured. Until that occurs, the ability to count correctly fatal and nonfatal serious work-related injuries will be diminished significantly. The work-related fatal-injury rates reported herein are possibly subject to some sources of bias, namely, the lack of exact information on the worker population size by age, occupation, and industry beyond that for the 1980 California census. While years close to the census year may be a meaningful estimate for this purpose, with population growth and the increasing proportion of the population over age 65 who are continuing work, the accuracy of the counts are open to criticism, and hence the work must be properly enumerated more frequently. The findings Our findings show that 83 percent of all fatal work-related injuries among people over 64 years of age are missed by the current notification system in California. This finding may apply to other states (or countries) that use a similar process. Deaths among older workers cannot be ignored by the uncertainty of their contribution in the work force. Our results do confirm the earlier findings reported by NIOSH, Division of Safety Research (1989)) where the highest traumatic occupational fatal-injury rates were observed among those over the age of 65. Our findings with regard to the intentionality of the injury

234

vary from the Division of Safety Research (DSR) report. The DSR, from 1980 to 1985, reports that 13 percent of the fatal injuries were from homicide, whereas, our findings for older workers are more than double that figure (27% ) . There is very little information in the scientific literature on fatal injuries among older workers, possibly because members in the older work force represents a small proportion of the total number gainfully employed in the United States. Nonetheless, our data indicate that older workers are exposed to energy sources and high risk of injury, particularly those who use motor vehicles, those exposed to assault, etc. The information on homicide is very remarkable in its own right in that the workers are exposed to the probability of assault by the nature of their occupations as security guards, bartenders, etc. (Kraus, 1987). It is now time for those in government and the private sector to combine energies to address exposure factors in these occupations and all segments of the older work force. Countermeasures to reduce exposure to assaults have long been available, but standards for their implementation are lacking. OSHA must evaluate, critically, the nature of the fatal and nonfatal injuries in this segment of the work force and address more carefully strategies to reduce significantly these exposures. Studies of specific occupation and industrial groups at high risk of injury are needed, including the self-employed. This segment of the work force is estimated to be between 30 to 40 percent of the total work force in California, yet standards to reduce fatal and nonfatal injury exposures are lacking. It should also be recognized that the older work force is not often employed full-time, but for many, part-time employment is a necessity to augment retirement income. This was evident on examination of the occupation and industry on the death certificate. “Usual” occupation and industry are recorded on the certificate, but the nature of the exposure and circumstances of death often indicated different types of work associated with the death. Careful documentation of the nature of the exposures among older workers is essential if we are to reduce exposure to fatal injuries while at work. Significant numbers of deaths in older persons in California were associated with farm-tractor overturns not unlike the farm-tractor associated death rates reported by the Centers for Disease Control (1983). The frequency of these incidents among persons whose “usual” occupations were not farming suggests that some of these deaths may involve “gentleman” farmers who may have little or no skills in operating complex and hazardous farm implements. Farmers and farm laborers are exposed to numerous sources of injury, and even in small-scale operations, risks are genuine (Center for Disease Control, 1983) and should be the focus of countermeasures. Responsibility for these countermeasures appears to be lost in the bureaucratic gaps among OSHA, the U.S. Department of Agriculture, U.S. Department of Health and Human Services, and related state or local agencies.

235 REFERENCES Baker, E.L., Honchar, P.A., Fine, L.J., 1989. Surveillance in occupational health and safety. I. Surveillance in occupational illness and injury: Concepts and content. Amer. J. Public Health, Suppl., 79: 9-11. Bureau of Labor Statistics, 1987. Occupational Injuries and Illnesses in the United States by Industry, 1985. U.S. Department of Labor, Bulletin 2278, U.S. Government Printing Office, Washington, DC May. California Department of Health Services, 1987. California Occupational Mortality, Health Data and Statistics Branch, Sacramento, CA. Centers for Disease Control, 1983. Farm-tractor tality Weekly Rep., 32: 481-483.

associated

deaths - Georgia. Morbidity

and Mor-

Commission on Professional and Hospital Activities, 1978. The International Classification of Diseases, 9th Revision, Clinical Modification. Edwards Brothers, Inc., Ann Arbor, MI. Division of Safety Research, 1989. National Traumatic Occupational Fatalities: 1980-1985. DHHS (NIOSH) Publication No. 89,116, Cincinnati, OH. Hanrahan, L.P. and Mob M.B., 1989. Surveillance in occupational health and safety. VIII. Injury surveillance. Amer. J. Public Health, Suppl., 79: 38-45. Harrison, J.E. and Frommer, M.S., 1986. Work-Related Fatilities in Australia. A review and proposals for a study of traumatic work-related deaths. Worksafe Australia National Occupational Health and Safety Commission. Syndey, NSW, Australia, July. Kraus, J., 1987. Homicide while at work: Persons, industries, and occupations at high risk. Amer. tJ. Public Health, 77: 830-832. Pollack, E.A. and Keiming, D.G., 1987. Counting Injuries and Illnesses in the Workplace: Proposals for a Better System. National Academy Press, Washington, DC, p. 4. U.S. Bureau of the Census, 1980-1982. Alphabetical Index of Industries and Occupations, U.S. Government Printing Office, July 1980 through November 1982.

1980,