- Email: [email protected]
Epidemiology of ocular trauma in Australia
Epidemiology of Ocular Trauma in Australia Cathy A. McCarty, PhD, MPH, Cara L. H. Fu, GradDip (IT), Hugh R. Taylor, MD, FRACO Purpose: To describe the prevalence and risk factors of ocular trauma in a representative sample of Australians aged 40 and over who reside in the state of Victoria. Design: Population-based cross-sectional study. Participants: Australians aged 40 years and older living in Victoria. Methods: Cluster, stratified sampling was used to identify permanent residents for a population-based study of eye disease. A standardized examination that included visual acuity and information about ocular trauma was conducted. Main Outcome Measures: Self-reported history of ocular trauma and circumstances surrounding the events. Results: A total of 3271 (83% of eligible) Melbourne residents and 1473 (92% of eligible) rural residents were examined. The overall rate of eye injury history in Victoria was 21.1% (95% confidence limits [CL] 19.6%, 22.5%). Men were far more likely than women to have ever experienced an eye injury (34.2% versus 9.9%), and rural men were more likely than Melbourne men to have ever had an eye injury (42.1% versus 30.5%). The workplace accounted for the majority of eye injuries (60%), followed by the home (24%). The location with the highest percent of people reporting the use of eye protection at the time of the injury was the workplace (18.5%); the workplace accounted for the lowest rate of hospitalization (4.9%). The industry with highest cumulative rate of eye injuries was communication (14 per 1000), whereas the highest occupation-specific cumulative rates of eye injury were recorded for tradespersons (18 per 1000). Conclusions: Although ocular trauma is usually not associated with bilateral vision impairment, it is a major public health problem in Australia. Rural men, people engaged in hammering or sport, and those in the trades are at highest risk and require specific, targeted, prevention messages. Ophthalmology 1999;106:1847–1852 Ocular trauma is a major cause of ocular morbidity globally, although it usually does not result in bilateral vision impairment.1,2 Reported risk factors for ocular trauma have included male gender, workplace and road accidents, and lower socioeconomic class.1,2 The impact of ocular trauma on the healthcare system and community is potentially enormous and associated with lost days of work.1 It has been conservatively estimated that 29,000 eye injuries occur annually in Australia, at a total cost of $155 million.3 Despite the public health importance of ocular trauma, there are relatively few population-based data on the prevalence of and risk factors for ocular trauma.4 – 8 Most data are derived from hospital records, where the number of people at risk cannot be determined accurately. Data from hospital sources without reference to the population at risk can bias results toward the more serious cases of ocular
Originally received: December 30, 1998. Revision accepted: May 13, 1999. Manuscript no. 98823. From the Centre for Eye Research Australia, Melbourne, Australia. Supported in part by grants from the National Health and Medical Research Council, Canberra; the Victorian Health Promotion Foundation, Melbourne; the Ansell Ophthalmology Foundation, Sydney; the Estate of the late Dorothy Edols, Melbourne; and the Jack Brockhoff Foundation, Melbourne, Australia. Address correspondence to Cathy A. McCarty, PhD, MPH, Centre for Eye Research Australia, University of Melbourne, 32 Gisborne Street, East Melbourne, VIC 3002, Australia. E-mail: [email protected]. unimelb.edu.au.
trauma in the community and underestimate the true prevalence of ocular trauma. To design targeted public health campaigns to reduce the incidence of ocular trauma in the community, it is first necessary to know which segments of the community are at greatest risk of eye injuries. The purpose of this study is to describe the prevalence of and risk factors for ocular trauma in a representative sample of Victorian adults.
Methods Details of the Visual Impairment Project have been published previously.9 Briefly, a stratified, cluster sample was employed to obtain a representative sample of adults aged 40 and over who had resided in their homes for at least 6 months. In urban Melbourne, nine pairs of census collector districts were randomly selected, and in rural Victoria, four pairs of census collector districts were randomly selected. Participants were recruited via a household census and invited to attend a locally established examination site. A brief questionnaire was administered at the doorstep to collect information about demographics, use of spectacles, and use of eye care services. The protocol was approved by the Human Research and Ethics Committee at the Royal Victorian Eye and Ear Hospital. The standardized examination at the test site included presenting and best-corrected visual acuity, visual fields, intraocular pressure, dilation, personal behavior and health interview, and clinical ophthalmic examination with lens and fundus photography. A slit lamp was used to examine the anterior segment; direct and indirect ophthalmoscopy were used to examine the posterior segment.
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Ophthalmology Volume 106, Number 9, September 1999 Table 1. Self-reported History of at Least One Eye Injury by Age, Gender, and Cohort Age Group (yrs)
Gender
Urban (n ⴝ 3260)
Rural (n ⴝ 1456)
Weighted Population Total (95% CL)
40–49
Male Female Male Female Male Female Male Female Male Female Male Female Male Female
114/356 (32.0%) 51/464 (11.0%) 147/444 (33.1%) 54/531 (10.2%) 136/427 (31.9%) 35/434 (8.1%) 53/220 (24.2%) 26/223 (11.7%) 9/56 (16.1%) 7/88 (8.0%) 0/3 (0%) 1/14 (9.9%) 30.5% (27.6%, 33.3%) 9.9% (8.4%, 11.4%) 19.4% (18.1%, 21.0%)
93/198 (47.0%) 27/236 (11.4%) 86/179 (48.0%) 21/176 (11.9%) 63/148 (42.6%) 17/172 (9.9%) 42/132 (31.8%) 7/137 (5.1%) 8/30 (26.7%) 1/39 (2.6%) 0/6 (0%) 0/3 (0%) 42.1% (36.8%, 47.5%) 9.6% (7.1%, 12.0%) 25.1% (22.2, 27.9%)
36.3% (31.1%, 41.6%) 11.1% (8.09%, 14.1%) 37.4% (32.7%, 42.1%) 10.7% (7.91%, 13.4%) 35.2% (30.5%, 39.9%) 8.7% (6.02%, 11.4%) 26.6% (20.7%, 32.6%) 9.6% (5.62%, 13.6%) 19.4% (8.64%, 30.1%) 6.3% (1.03%, 11.6%) 0% 5.0% (0%, 16.9%) 34.2% (31.5%, 36.9%) 9.9% (8.6%, 11.2%) 21.1% (19.6%, 22.5%)
50–59 60–69 70–79 80–89 90⫹ All ages Standardized total CL ⫽ confidence limits.
Unilateral visual acuity was measured on a 4-meter Early Treatment Diabetic Retinopathy Study LogMAR chart with spectacles if used. A Humphrey autorefractor (model 597, Humphrey Instruments) was used with participants who had presenting distance visual acuity less than 6/6 ⫺ 2 and subjectively refined. Up to three causes of visual impairment were coded on the clinical examination for anyone with corrected visual acuity ⬍6/12 in either eye. Self-reported history of ocular trauma was ascertained with the following question: “Have you ever had any eye injury, such as a sports injury, wound, or trauma requiring doctor’s care?” Participants who had experienced eye injury were asked to provide details about the cause, place of occurrence, and treatment of that injury, as well as whether they were wearing eye protection at the time of the injury. Details related to the circumstances of the eye injuries were queried for the two most recent injuries to each eye or both eyes simultaneously in the urban cohort and the four most recent injuries to each eye or both eyes simultaneously in the rural cohort. These questions were adapted from a questionnaire used in a hospital-based study of eye injuries.4 Interview data were entered directly into specially designed Paradox data entry forms (Carel Corp., Ottawa, Canada) with internal consistency checks. All other data were doubly entered from self-coding forms and verified. All statistical analyses were performed with SAS version 6.1 (SAS Institute, Cary, NC). The rural data were weighted to the Melbourne population using 1996 census data from the Australian Bureau of Statistics.10 Standard errors for the weighted prevalence were adjusted to account for the cluster design of the study.11 Cluster sampling can result in artificially low estimates of the variance because people are more alike within than between clusters. Therefore, the sampling design must be taken into account in the analysis. Ninety-five percent confidence limits (CL) around the age-standardized rates were computed with the standard error of the estimate.12 The age distribution of the Melbourne participants was used as the standard population for direct age standardization. Ninety-five percent CLs around the rates of vision impairment due to ocular trauma and the annual rate of eye injury were calculated based on the expected value of a Poisson random variable. P ⬍ 0.05 was considered statistically significant.
Results A total of 3271 (83% of eligible) urban residents and 1473 (92% of eligible) rural residents were examined. The participants did not
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differ significantly from the nonparticipants, except for the language spoken at home.13 The participation rates were 85% for English speakers, 76% for Greek speakers, 78% for Italian speakers, and 79% for other language speakers. The urban residents ranged in age from 40 to 98 years (mean, 58) and 54% were women. The rural residents ranged in age from 40 to 103 years (mean, 60) and 52% were women. Interview data were available for 3260 (99.7%) of the urban participants and 1456 (98.8%) of the rural participants. A history of at least one eye injury was reported by 633 (19.4%) of the urban participants and 365 (25.1%) of the rural participants (Table 1). The design effect was found to be 1.56 and has been incorporated into all of the 95% CLs around the point estimates. The 95% CLs of the urban and rural cohorts do not overlap after controlling for age and design effect. Men were far more likely than women to have ever experienced an eye injury (34.2%, 95% CL 31.5%, 36.9% versus 9.9%, 95% CL 8.6%, 11.2%) and rural men were more likely than urban men to have ever had an eye injury (42.1%, 95% CL 36.8%, 47.5% versus 30.5%, 95% CL 27.6%, 33.3%). There was a trend toward decreasing lifetime history of eye injury with age in both genders and cohorts. The overall rate of eye injury history in Victoria was 21.1% (95% CL 19.6%, 22.5%). The cohort effect was explored further by plotting the cumulative prevalence of eye trauma at the age that the first trauma occurred by age cohort (Fig 1). A significant linear trend was observed (P ⬍ 0.05), indicating the younger birth cohorts were more likely to experience eye injuries at the same life periods as the older birth cohorts. The data are similar for the genders and locations (data not shown). For most age cohorts, the steepest slope of the line occurs in the late teens/early 20s, indicating the highest risk age group. We estimated the annual rate of eye injuries and hospitalizations based on the average number of injuries and hospitalizations that were reported in the previous 5 years. The estimated weighted annual rate of eye injuries in this cohort was 11.4 per 1000 population (95% CL 8.56%, 14.9%), whereas the estimated weighted annual rate of hospitalizations due to eye injuries was 0.57 per 1000 population (0.12, 1.86). The cumulative number of injuries that occurred per eye was 799 to the right eye, 646 to the left eye, and 143 to both eyes simultaneously. Because details about previous eye injuries were queried for up to 2 episodes in each eye or both eyes simultaneously in the urban cohort and up to 4 episodes per eye or both eyes simultaneously in the rural cohort, data are not available for urban participants who had more than 6 total injuries and rural
McCarty et al 䡠 Ocular Trauma in Australia
Figure 1. Cumulative lifetime prevalence of any eye trauma by age cohort.
participants who had more than 12 total injuries. The maximum cumulative number of injuries reported was 20. Full details are not available for 1 urban resident with 9 reported injuries, 2 urban residents with 10 reported injuries, and 1 urban resident with 20 lifetime injuries. Full details about all lifetime injuries are not available for the following rural participants: 1 person with 10 injuries, 6 people with 12 injuries, and 1 person with 20 injuries. This would affect the results by slightly decreasing the cumulative number of injuries per population at risk. Of the 1426 cumulative eye injuries with complete details about the circumstance of the injury that were reported in this cohort, 117 (8%) resulted in hospitalization. The rate of hospitalization in people who reported use of proper protective eyewear at the time of the injury was less than those who did not wear protective eyewear at the time of the injury (5 of 75 people [6.3%] compared with 117 of 946 [12.4%]). Of the 117 hospitalizations, 6 eyes of 6 people were enucleated because of the trauma; none of these people had visual acuity ⬍6/18 in their other eye. Of the 1197 injured eyes, 75 (6.3%) had visual acuity less than 6/18. In 11
(14.7%) of the eyes with prior injury that had visual acuity ⬍6/18, ocular trauma was the cause of the impaired vision. In this study population, no one had bilateral vision impairment due to ocular trauma, although two people with vision loss due to ocular trauma in one eye had vision impairment due to another cause in the other eye and were thus bilaterally vision impaired. The overall rate of unilateral vision impairment due to ocular trauma was 12/4735 (0.25%; 95% CL, 0.13%, 0.44%). Descriptive information about the circumstances of the eye injuries that occurred in this cohort is summarized in Tables 2– 4. The workplace accounted for the majority of eye injuries (60%), followed by the home (24%; Table 2). The location of the highest percent of people wearing eye protection at the time of the injury was the workplace (18.5%). Correspondingly, the workplace accounted for the lowest rate of hospitalization due to the eye injury (4.9%). The most common causes of eye injury were steel-metal hitting the eye (31%), drilling-grinding-sanding (11%), and welding (9%) (Table 3). The largest proportion of people wearing eye protection at the time of the eye injury was reported in the
Table 2. Cumulative Distribution of Place of Eye Injury, Whether Eye Protection Was Worn at the Time of Injury, and Whether Injury Resulted in Hospital Admission Place of Injury Workplace Home Recreation Travel Sport Other Total
No. of Injuries (% of total)
% (95% CL) Wearing Eye Protection at the Time of Injury
% (95% CL) Admitted to Hospital
838 (60%) 333 (24%) 105 (7.5%) 59 (4.2%) 51 (3.6%) 18 (1.3%)
18.5% (15.9, 21.1) 5.1% (2.7, 7.5) 5.7% (1.3, 10.1) 3.4% (0, 8.0) 0% 5.6% (0, 16.1)
4.9% (3.4, 6.4) 12.9% (9.3, 16.5) 19.0% (11.5, 26.6) 23.7% (12.9, 34.6) 7.8% (0.5, 15.2) 22.2% (3.0, 41.4)
1404
13% (11.1, 14.6)
9.0% (7.5, 10.5)
CL ⫽ confidence limits.
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Ophthalmology Volume 106, Number 9, September 1999 Table 3. Cumulative Distribution of Cause of Eye Injury, Whether Eye Protection Was Worn at the Time of Injury, and Whether Injury Resulted in Hospital Admission
Cause of Eye Injury
No. of Injuries (% of total)
% (95% CL) Wearing Eye Protection at the Time of Injury
% (95% CL) Admitted to Hospital
Steel/metal Drilling/grinding/sanding Welding Other foreign body Garden planting Dust/dirt Other Alkali/chemical burn Sports (other than racquet) Assault/firearm Mower/snipper/wood chopping Hammering Racquet sports Motor car/bike accident Thermal burn/explosion/fire cracker Finger poked in eye Glass Blunt object
430 (30.7) 157 (11.2) 129 (9.2) 100 (7.1) 88 (6.3) 70 (5.0) 67 (4.8) 66 (4.7) 46 (3.3) 42 (3.0) 38 (2.7) 31 (2.2) 28 (2.0) 27 (1.9) 25 (1.8) 24 (1.7) 18 (1.3) 17 (1.2)
13.3% (10.1, 16.5) 30.6% (23.4, 37.8) 31.0% (23.0, 39.0) 1.0% (0, 3.0) 3.4% (0, 7.20) 15.7% (7.19, 24.2) 6.0% (0.30, 11.6) 6.1% (0.30, 11.8) 2.17% (0, 6.4) 2.4% (0, 7.0) 7.9% (0, 16.5) 6.5% (0, 15.1) 0% 11.1% (0, 22.9) 4.0% (0, 11.7) 0% 16.7% (0, 33.9) 5.9% (0, 17.1)
4.9% (2.9, 6.9) 2.5% (0.1, 5.0) 0.8% (0, 2.3) 10.0% (4.12, 15.9) 8.0% (2.30, 13.6) 0% 11.9% (4.2, 19.7) 12.1% (4.3, 20.0) 8.7% (0.6, 16.8) 19.0% (7.2, 30.9) 13.1% (2.4, 23.9) 12.9% (1.1, 24.7) 10.7% (0, 22.2) 70.4% (53.1, 87.6) 40.0% (20.8, 59.2) 4.27% (0, 12.2) 22.2% (3.02, 14.4) 35.3% (12.6, 58.0)
CL ⫽ confidence limits.
circumstances of drilling-grinding-sanding (31%) and welding (31%), whereas the highest proportion of people admitted to hospital was reported for thermal burns-explosion-fire cracker (40%) and motor car or bike accidents (70%). For those people who were wearing eye protection at the time of their eye injury, the most common form of protection was protective spectacles, followed by safety goggles (Table 4). Only 143 (10.2%) people were wearing correct protective eyewear at the time of their eye injury. Caution needs to be taken in interpreting the data in Tables 2– 4 because they reflect only the people who experienced an eye injury and not the people who were at risk but did not experience an injury serious enough to seek medical attention. Cumulative rates of eye injuries that occurred at work were calculated based on the person years at risk in various occupations and industries (Tables 5 and 6). The industry with the highest cumulative rate of eye injuries was communication (14 per 1000), followed closely by construction (13 per 1000) (Table 5), whereas the highest industry-specific cumulative rates of eye injury were recorded for tradespersons (18 per 1000), student or nonclassifiable trainees (16 per 1000), and managers and administrators (11 per 1000) (Table 6).
Discussion To our knowledge, this is the first population-based report of eye injuries in Australia, and the data are important for public health education. We found eye injuries requiring doctor’s treatment to be a significant public health problem, with more than 20% of Victorians aged 40 and over having had at least one eye injury during their lifetime. Our overall rate of 34% in men is substantially higher than the rate of 20% reported in white men in the Baltimore Eye Survey, although our rate of 9.9% in women is comparable to the reported rate of 7.7% in white females in that study.8 Researchers in the Baltimore Eye Survey noted a decrease
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in ocular injuries in the older age groups similar to the decrease that we observed in the Visual Impairment Project. There are several potential explanations for this observed decrease. First, older people might truly have experienced less ocular trauma during their lifetimes owing to decreased exposure to high-risk situations. Second, a systematic recall bias may exist in this cohort about injuries that occurred when the respondents were younger such that they are not recalled. Third, a survivor bias could exist in this cohort, where people who experienced eye injuries during their lifetime are at greater risk of mortality and therefore have not survived long enough to participate in our study. Although the incidence of eye injuries has been shown to decrease with age, the average annual hospital discharge rate for ocular trauma has been shown to increase dramatically after the age of 80 years.5 This increased rate of hospitalization in the elderly could be due to falls leading to more serious injuries in this age group. Not only was the lifetime prevalence of eye injuries higher in the Visual Impairment Project than the Baltimore Eye Survey,8 but also the estimated annual incidence was higher (11.4 per 1000 compared with 4.1 in white men and 1.8 in white women). This compares to the expected number of eye injuries requiring medical attention in 1985 per 1000 New England adults, which ranged from 4.1 in Rhode Island to 15.3 in New Hampshire.3 The difference between the states could be due to different age structures and occupations associated with ocular trauma. In the state of Victoria, the estimated annual incidence rate translates to 9755 eye injuries serious enough to require medical attention in people aged 40 and over each year based on 1996 census figures. A study conducted at the Royal Victorian Eye and Ear Hospital from 1989 –1991 estimated that 31,000 Victorians of all ages sustain eye injuries annually at a cost of $37 million (Fong LP, MD
McCarty et al 䡠 Ocular Trauma in Australia Table 4. Eye Protection Worn at the Time of Injury Type of Eye Protection Worn None Protective spectacles* Safety goggles* Shield* Ordinary spectacles Sunglasses Contact lenses
No. (%) 1224 (87) 58 (4.1) 50 (3.6) 35 (2.5) 30 (2.1) 4 (0.3) 3 (0.2)
* Correct protective eyewear.
thesis, University of Melbourne, 1995), which means that slightly under one third of all eye injuries occur in people aged 40 years and over. In close agreement, we found in the Visual Impairment Project that 40% of all reported lifetime eye injuries occurred at age 40 years and older. This figure could be a slight overestimate owing to recall bias and the fact that details were not available for all injuries. We estimate that 488 Victorians in this age group are hospitalized annually because of their eye injuries. The workplace accounted for the majority of all injuries in the current study, and less than 20% of the workers had been wearing any form of eye protection at the time of the injury. Very similar results were found in a study of patients treated at the Royal Victorian Eye and Ear Hospital,4 in which the workplace accounted for 44% of all injuries and only 16% of all patients injured at the workplace were wearing correct protective equipment (the appropriately designed or rated protective spectacles, goggles, or shield for that particular hazardous activity), although 36% reported that they were wearing some form of protective eyewear at the time of the injury (ordinary spectacles, sunglasses).4 Researchers found that use of no or incorrect protective eyewear was particularly high for workers at home or those employed in small shops. A hospital-based study in the United States also found that approximately half of all injuries occurred at the workplace, but 66% reported wearing protective eyewear at the time of the injury.7 In the
National Eye Trauma System Registry in the United States, less than 10% of injured workers reported use of protective eyewear at the time of the injury.6 These data highlight the need for education and enforcement of regulations about the use of ocular protection in the workplace. Because 17% of people reported wearing only ordinary spectacles for eye protection at the time of their injury, it is important to educate people about the use of proper eye protection. In the current study, sports accounted for more than 5% of all eye injuries, and less than 2% of people injured while playing sports were wearing eye protection at the time of the injury. The rate of hospitalization for sports-related injury was about 10%. At the Royal Victorian Eye and Ear Hospital, sports injuries accounted for 5% of all injuries but 22% of hospital admissions and carried a high ocular morbidity.14 The most frequent sports-related eye injuries in this study were squash, Australian Rules football, indoor and outdoor cricket, and badminton. In a study of patients with sports-related ocular trauma who were treated at a tertiary care center in the United States, 14% required hospitalization and only 5% had worn eye protection at the time of the injury.15 These data indicate that playing sports is a major cause of ocular trauma, especially trauma resulting in hospitalization, and that again education is needed to encourage people to wear proper eye protection. Elite athletes should serve as role models for the use of eye protection in sports,16 and public health legislation could be considered for amateur sports as a means to increase the use of protective eyewear during all types of sports. The causes of half of all eye injuries in the current study were steel-metal, drilling-grinding-sanding, and welding; less than one third of people injured due to these causes were wearing eye protection at the time of the injury. The Royal Victorian Eye and Ear Hospital study found that tools and metal accounted for the majority (41%) of all eye injuries.8 In contrast, assault accounted for the majority (41%) of all eye injuries seen at a public medical center in Los Angeles.17 A commonly performed activity in the community is gardening, which was responsible for 10% of all injuries in this cohort; less than 10% of people injured due
Table 5. Industry-specific Cumulative Rates of Eye Injury that Occurred at Work
Industry
Cumulative No. of Eye Injuries at Work
Person-years at Risk
Cumulative Prevalence of Eye Injuries per 1000 Person-years at Risk [% (95% CL)]
Agriculture, forestry, fishing, and hunting Mining Manufacturing Electricity, gas, and water Construction Wholesale and retail trade Transport and storage Communication Finance property and business services Public administration and defense Community services Recreation, personal and other services Nonclassifiable economic units (e.g., students)
110 17 218 11 107 79 52 43 8 28 0 33 28
16389 1400 30608 1932 8420 22830 6766 3152 9478 8103 17727 27241 43787
6.7 (5.5, 8.0) 12.1 (6.4, 17.9) 7.1 (6.2, 8.1) 5.7 (2.3, 9.0) 12.7 (10.3, 15.1) 3.5 (2.7, 4.2) 7.7 (5.6, 9.8) 13.6 (9.6, 17.7) 0.8 (0.3, 1.4) 3.5 (2.2, 4.7) 0 1.2 (0.8, 1.6) 0.6 (0.4, 0.9)
CL ⫽ confidence limits.
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Ophthalmology Volume 106, Number 9, September 1999 Table 6. Occupation-specific Cumulative Rates of Eye Injury that Occurred at Work Occupation
No. of Eye Injuries at Work
Person-years at risk
Cumulative Prevalence of Eye Injuries per 1000 Person-years at Risk [% (95% CL)]
Managers and administrators Professionals Paraprofessionals Tradespersons Clerks Salespersons/personal service workers Plant and machine operators and drivers Laborers and related workers Home duties Retired Unemployed Student or nonclassifiable trainee Armed services, no specific occupation Volunteer Injured/sick/invalid Traveling/tourist/on holiday Prisoner of war Refugee/in migrant camp On paid leave
144 40 34 268 21 14 83 88 8 10 2 15 6 0 1 0 0 0 0
23,788 14,210 7447 21,573 19,772 11,823 13,192 21,882 48,384 12,641 599 1270 1500 29 694 203 69 10 2
11.4 (10.0, 12.7) 3.7 (2.7, 4.7) 6.3 (4.51, 8.09) 17.9 (16.2, 19.7) 1.4 (0.88, 1.92) 1.6 (0.88, 2.32) 9.08 (7.46, 10.7) 5.41 (4.44, 6.38) 0.24 (0.1, 0.38) 1.11 (0.53, 1.69) 3.66 (0, 8.47) 16.3 (9.3, 23.2) 5.35 (1.66, 9.02) 0 1.48 (0, 4.33) 0 0 0 0
CL ⫽ confidence limits.
to this cause were wearing eye protection at the time. Some eye injuries will inevitably remain unavoidable (such as being poked in the eye) because people do not wear eye protection at all times. Therefore, public health education efforts should be concentrated on common activities that put people at higher risk of eye injuries, including high-risk occupations such as the trades that involve hammering and welding, sports, gardening, and the use of other tools at home. In these circumstances, everyone should be encouraged to wear protective spectacles. This could reduce the incidence of eye injuries and the burden of ocular trauma and its associated costs on the community. In summary, ocular trauma continues to be an important public health problem in Victoria and Australia, affecting more than one fifth of the adult population. Similar rates and circumstances have been documented in two studies with very different methodologies, the population-based Visual Impairment Project, and the Royal Victorian Eye and Ear Hospital– based study,4 thus providing validity to both studies. Public health education is clearly warranted to raise awareness about the risk of ocular trauma and the appropriate ocular protection to prevent eye injuries, and further public health legislation should be considered where appropriate and feasible.
References 1. Thylefors B. Epidemiological patterns of ocular trauma. Aust N Z J Ophthalmol 1992;20:95– 8. 2. Ne´grel AD, Thylefors B. The global impact of eye injuries. Ophthalmic Epidemiol 1998;5:143– 69. 3. Glynn RJ, Seddon JM, Berlin BM. The incidence of eye injuries in New England adults. Arch Ophthalmol 1988;106:785–9.
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4. Fong LP. Eye injuries in Victoria, Australia. Med J Aust 1995;162:64 – 8. 5. Klopfer J, Tielsch JM, Vitale S, et al. Ocular trauma in the United States. Eye injuries resulting in hospitalization, 1984 through 1987. Arch Ophthalmol 1992;110:838 – 42. 6. Dannenberg AL, Parver LM, Brechner RJ, Khoo L. Penetration eye injuries in the workplace. The National Eye Trauma System Registry. Arch Ophthalmol 1992;110:843– 8. 7. Schein OD, Hibberd PL, Shingleton BJ, et al. The spectrum and burden of ocular injury. Ophthalmology 1988;95:300 –5. 8. Katz J, Tielsch JM. Lifetime prevalence of ocular injuries from the Baltimore Eye Survey. Arch Ophthalmol 1993;111: 1564 – 8. 9. Livingston PM, Carson CA, Stanislavsky YL, et al. Methods for a population-based study of eye disease: the Melbourne Visual Impairment Project. Ophthalmic Epidemiol 1994;1: 139 – 48. 10. Australian Bureau of Statistics. 1996 Census of Population and Housing. Canberra: ABS; 1997. 11. Cochran WG. Sampling Techniques, 3rd ed. New York: Wiley, 1977. (Wiley Series in probability and mathematical statistics; A Wiley publication in applied statistics). 12. Statistical Methods in Cancer Research. Vol. II. Lyon: International Agency for Research on Cancer, 1989; p 58 – 61. 13. Livingston PM, Lee SE, McCarty CA, Taylor HR. A comparison of participants with non-participants in a populationbased epidemiologic study: the Melbourne Visual Impairment Project. Ophthalmic Epidemiol 1997;4:73– 81. 14. Fong LP. Sports-related eye injuries. Med J Aust 1994;160: 743–50. 15. Larrison WI, Hersh PS, Kunzweiler T, Shingleton BJ. Sportsrelated ocular trauma. Ophthalmology 1990;97:1265–9. 16. Vinger PF. The incidence of eye injuries in sports. Int Ophthalmol Clin 1981;21:21– 46. 17. Liggett PE, Pince KJ, Barlow W, et al. Ocular trauma in an urban population. Review of 1132 cases. Ophthalmology 1990;97:581– 4.
Originally received: December 30, 1998. Revision accepted: May 13, 1999. Manuscript no. 98823. From the Centre for Eye Research Australia, Melbourne, Australia. Supported in part by grants from the National Health and Medical Research Council, Canberra; the Victorian Health Promotion Foundation, Melbourne; the Ansell Ophthalmology Foundation, Sydney; the Estate of the late Dorothy Edols, Melbourne; and the Jack Brockhoff Foundation, Melbourne, Australia. Address correspondence to Cathy A. McCarty, PhD, MPH, Centre for Eye Research Australia, University of Melbourne, 32 Gisborne Street, East Melbourne, VIC 3002, Australia. E-mail: [email protected]. unimelb.edu.au.
trauma in the community and underestimate the true prevalence of ocular trauma. To design targeted public health campaigns to reduce the incidence of ocular trauma in the community, it is first necessary to know which segments of the community are at greatest risk of eye injuries. The purpose of this study is to describe the prevalence of and risk factors for ocular trauma in a representative sample of Victorian adults.
Methods Details of the Visual Impairment Project have been published previously.9 Briefly, a stratified, cluster sample was employed to obtain a representative sample of adults aged 40 and over who had resided in their homes for at least 6 months. In urban Melbourne, nine pairs of census collector districts were randomly selected, and in rural Victoria, four pairs of census collector districts were randomly selected. Participants were recruited via a household census and invited to attend a locally established examination site. A brief questionnaire was administered at the doorstep to collect information about demographics, use of spectacles, and use of eye care services. The protocol was approved by the Human Research and Ethics Committee at the Royal Victorian Eye and Ear Hospital. The standardized examination at the test site included presenting and best-corrected visual acuity, visual fields, intraocular pressure, dilation, personal behavior and health interview, and clinical ophthalmic examination with lens and fundus photography. A slit lamp was used to examine the anterior segment; direct and indirect ophthalmoscopy were used to examine the posterior segment.
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Ophthalmology Volume 106, Number 9, September 1999 Table 1. Self-reported History of at Least One Eye Injury by Age, Gender, and Cohort Age Group (yrs)
Gender
Urban (n ⴝ 3260)
Rural (n ⴝ 1456)
Weighted Population Total (95% CL)
40–49
Male Female Male Female Male Female Male Female Male Female Male Female Male Female
114/356 (32.0%) 51/464 (11.0%) 147/444 (33.1%) 54/531 (10.2%) 136/427 (31.9%) 35/434 (8.1%) 53/220 (24.2%) 26/223 (11.7%) 9/56 (16.1%) 7/88 (8.0%) 0/3 (0%) 1/14 (9.9%) 30.5% (27.6%, 33.3%) 9.9% (8.4%, 11.4%) 19.4% (18.1%, 21.0%)
93/198 (47.0%) 27/236 (11.4%) 86/179 (48.0%) 21/176 (11.9%) 63/148 (42.6%) 17/172 (9.9%) 42/132 (31.8%) 7/137 (5.1%) 8/30 (26.7%) 1/39 (2.6%) 0/6 (0%) 0/3 (0%) 42.1% (36.8%, 47.5%) 9.6% (7.1%, 12.0%) 25.1% (22.2, 27.9%)
36.3% (31.1%, 41.6%) 11.1% (8.09%, 14.1%) 37.4% (32.7%, 42.1%) 10.7% (7.91%, 13.4%) 35.2% (30.5%, 39.9%) 8.7% (6.02%, 11.4%) 26.6% (20.7%, 32.6%) 9.6% (5.62%, 13.6%) 19.4% (8.64%, 30.1%) 6.3% (1.03%, 11.6%) 0% 5.0% (0%, 16.9%) 34.2% (31.5%, 36.9%) 9.9% (8.6%, 11.2%) 21.1% (19.6%, 22.5%)
50–59 60–69 70–79 80–89 90⫹ All ages Standardized total CL ⫽ confidence limits.
Unilateral visual acuity was measured on a 4-meter Early Treatment Diabetic Retinopathy Study LogMAR chart with spectacles if used. A Humphrey autorefractor (model 597, Humphrey Instruments) was used with participants who had presenting distance visual acuity less than 6/6 ⫺ 2 and subjectively refined. Up to three causes of visual impairment were coded on the clinical examination for anyone with corrected visual acuity ⬍6/12 in either eye. Self-reported history of ocular trauma was ascertained with the following question: “Have you ever had any eye injury, such as a sports injury, wound, or trauma requiring doctor’s care?” Participants who had experienced eye injury were asked to provide details about the cause, place of occurrence, and treatment of that injury, as well as whether they were wearing eye protection at the time of the injury. Details related to the circumstances of the eye injuries were queried for the two most recent injuries to each eye or both eyes simultaneously in the urban cohort and the four most recent injuries to each eye or both eyes simultaneously in the rural cohort. These questions were adapted from a questionnaire used in a hospital-based study of eye injuries.4 Interview data were entered directly into specially designed Paradox data entry forms (Carel Corp., Ottawa, Canada) with internal consistency checks. All other data were doubly entered from self-coding forms and verified. All statistical analyses were performed with SAS version 6.1 (SAS Institute, Cary, NC). The rural data were weighted to the Melbourne population using 1996 census data from the Australian Bureau of Statistics.10 Standard errors for the weighted prevalence were adjusted to account for the cluster design of the study.11 Cluster sampling can result in artificially low estimates of the variance because people are more alike within than between clusters. Therefore, the sampling design must be taken into account in the analysis. Ninety-five percent confidence limits (CL) around the age-standardized rates were computed with the standard error of the estimate.12 The age distribution of the Melbourne participants was used as the standard population for direct age standardization. Ninety-five percent CLs around the rates of vision impairment due to ocular trauma and the annual rate of eye injury were calculated based on the expected value of a Poisson random variable. P ⬍ 0.05 was considered statistically significant.
Results A total of 3271 (83% of eligible) urban residents and 1473 (92% of eligible) rural residents were examined. The participants did not
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differ significantly from the nonparticipants, except for the language spoken at home.13 The participation rates were 85% for English speakers, 76% for Greek speakers, 78% for Italian speakers, and 79% for other language speakers. The urban residents ranged in age from 40 to 98 years (mean, 58) and 54% were women. The rural residents ranged in age from 40 to 103 years (mean, 60) and 52% were women. Interview data were available for 3260 (99.7%) of the urban participants and 1456 (98.8%) of the rural participants. A history of at least one eye injury was reported by 633 (19.4%) of the urban participants and 365 (25.1%) of the rural participants (Table 1). The design effect was found to be 1.56 and has been incorporated into all of the 95% CLs around the point estimates. The 95% CLs of the urban and rural cohorts do not overlap after controlling for age and design effect. Men were far more likely than women to have ever experienced an eye injury (34.2%, 95% CL 31.5%, 36.9% versus 9.9%, 95% CL 8.6%, 11.2%) and rural men were more likely than urban men to have ever had an eye injury (42.1%, 95% CL 36.8%, 47.5% versus 30.5%, 95% CL 27.6%, 33.3%). There was a trend toward decreasing lifetime history of eye injury with age in both genders and cohorts. The overall rate of eye injury history in Victoria was 21.1% (95% CL 19.6%, 22.5%). The cohort effect was explored further by plotting the cumulative prevalence of eye trauma at the age that the first trauma occurred by age cohort (Fig 1). A significant linear trend was observed (P ⬍ 0.05), indicating the younger birth cohorts were more likely to experience eye injuries at the same life periods as the older birth cohorts. The data are similar for the genders and locations (data not shown). For most age cohorts, the steepest slope of the line occurs in the late teens/early 20s, indicating the highest risk age group. We estimated the annual rate of eye injuries and hospitalizations based on the average number of injuries and hospitalizations that were reported in the previous 5 years. The estimated weighted annual rate of eye injuries in this cohort was 11.4 per 1000 population (95% CL 8.56%, 14.9%), whereas the estimated weighted annual rate of hospitalizations due to eye injuries was 0.57 per 1000 population (0.12, 1.86). The cumulative number of injuries that occurred per eye was 799 to the right eye, 646 to the left eye, and 143 to both eyes simultaneously. Because details about previous eye injuries were queried for up to 2 episodes in each eye or both eyes simultaneously in the urban cohort and up to 4 episodes per eye or both eyes simultaneously in the rural cohort, data are not available for urban participants who had more than 6 total injuries and rural
McCarty et al 䡠 Ocular Trauma in Australia
Figure 1. Cumulative lifetime prevalence of any eye trauma by age cohort.
participants who had more than 12 total injuries. The maximum cumulative number of injuries reported was 20. Full details are not available for 1 urban resident with 9 reported injuries, 2 urban residents with 10 reported injuries, and 1 urban resident with 20 lifetime injuries. Full details about all lifetime injuries are not available for the following rural participants: 1 person with 10 injuries, 6 people with 12 injuries, and 1 person with 20 injuries. This would affect the results by slightly decreasing the cumulative number of injuries per population at risk. Of the 1426 cumulative eye injuries with complete details about the circumstance of the injury that were reported in this cohort, 117 (8%) resulted in hospitalization. The rate of hospitalization in people who reported use of proper protective eyewear at the time of the injury was less than those who did not wear protective eyewear at the time of the injury (5 of 75 people [6.3%] compared with 117 of 946 [12.4%]). Of the 117 hospitalizations, 6 eyes of 6 people were enucleated because of the trauma; none of these people had visual acuity ⬍6/18 in their other eye. Of the 1197 injured eyes, 75 (6.3%) had visual acuity less than 6/18. In 11
(14.7%) of the eyes with prior injury that had visual acuity ⬍6/18, ocular trauma was the cause of the impaired vision. In this study population, no one had bilateral vision impairment due to ocular trauma, although two people with vision loss due to ocular trauma in one eye had vision impairment due to another cause in the other eye and were thus bilaterally vision impaired. The overall rate of unilateral vision impairment due to ocular trauma was 12/4735 (0.25%; 95% CL, 0.13%, 0.44%). Descriptive information about the circumstances of the eye injuries that occurred in this cohort is summarized in Tables 2– 4. The workplace accounted for the majority of eye injuries (60%), followed by the home (24%; Table 2). The location of the highest percent of people wearing eye protection at the time of the injury was the workplace (18.5%). Correspondingly, the workplace accounted for the lowest rate of hospitalization due to the eye injury (4.9%). The most common causes of eye injury were steel-metal hitting the eye (31%), drilling-grinding-sanding (11%), and welding (9%) (Table 3). The largest proportion of people wearing eye protection at the time of the eye injury was reported in the
Table 2. Cumulative Distribution of Place of Eye Injury, Whether Eye Protection Was Worn at the Time of Injury, and Whether Injury Resulted in Hospital Admission Place of Injury Workplace Home Recreation Travel Sport Other Total
No. of Injuries (% of total)
% (95% CL) Wearing Eye Protection at the Time of Injury
% (95% CL) Admitted to Hospital
838 (60%) 333 (24%) 105 (7.5%) 59 (4.2%) 51 (3.6%) 18 (1.3%)
18.5% (15.9, 21.1) 5.1% (2.7, 7.5) 5.7% (1.3, 10.1) 3.4% (0, 8.0) 0% 5.6% (0, 16.1)
4.9% (3.4, 6.4) 12.9% (9.3, 16.5) 19.0% (11.5, 26.6) 23.7% (12.9, 34.6) 7.8% (0.5, 15.2) 22.2% (3.0, 41.4)
1404
13% (11.1, 14.6)
9.0% (7.5, 10.5)
CL ⫽ confidence limits.
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Ophthalmology Volume 106, Number 9, September 1999 Table 3. Cumulative Distribution of Cause of Eye Injury, Whether Eye Protection Was Worn at the Time of Injury, and Whether Injury Resulted in Hospital Admission
Cause of Eye Injury
No. of Injuries (% of total)
% (95% CL) Wearing Eye Protection at the Time of Injury
% (95% CL) Admitted to Hospital
Steel/metal Drilling/grinding/sanding Welding Other foreign body Garden planting Dust/dirt Other Alkali/chemical burn Sports (other than racquet) Assault/firearm Mower/snipper/wood chopping Hammering Racquet sports Motor car/bike accident Thermal burn/explosion/fire cracker Finger poked in eye Glass Blunt object
430 (30.7) 157 (11.2) 129 (9.2) 100 (7.1) 88 (6.3) 70 (5.0) 67 (4.8) 66 (4.7) 46 (3.3) 42 (3.0) 38 (2.7) 31 (2.2) 28 (2.0) 27 (1.9) 25 (1.8) 24 (1.7) 18 (1.3) 17 (1.2)
13.3% (10.1, 16.5) 30.6% (23.4, 37.8) 31.0% (23.0, 39.0) 1.0% (0, 3.0) 3.4% (0, 7.20) 15.7% (7.19, 24.2) 6.0% (0.30, 11.6) 6.1% (0.30, 11.8) 2.17% (0, 6.4) 2.4% (0, 7.0) 7.9% (0, 16.5) 6.5% (0, 15.1) 0% 11.1% (0, 22.9) 4.0% (0, 11.7) 0% 16.7% (0, 33.9) 5.9% (0, 17.1)
4.9% (2.9, 6.9) 2.5% (0.1, 5.0) 0.8% (0, 2.3) 10.0% (4.12, 15.9) 8.0% (2.30, 13.6) 0% 11.9% (4.2, 19.7) 12.1% (4.3, 20.0) 8.7% (0.6, 16.8) 19.0% (7.2, 30.9) 13.1% (2.4, 23.9) 12.9% (1.1, 24.7) 10.7% (0, 22.2) 70.4% (53.1, 87.6) 40.0% (20.8, 59.2) 4.27% (0, 12.2) 22.2% (3.02, 14.4) 35.3% (12.6, 58.0)
CL ⫽ confidence limits.
circumstances of drilling-grinding-sanding (31%) and welding (31%), whereas the highest proportion of people admitted to hospital was reported for thermal burns-explosion-fire cracker (40%) and motor car or bike accidents (70%). For those people who were wearing eye protection at the time of their eye injury, the most common form of protection was protective spectacles, followed by safety goggles (Table 4). Only 143 (10.2%) people were wearing correct protective eyewear at the time of their eye injury. Caution needs to be taken in interpreting the data in Tables 2– 4 because they reflect only the people who experienced an eye injury and not the people who were at risk but did not experience an injury serious enough to seek medical attention. Cumulative rates of eye injuries that occurred at work were calculated based on the person years at risk in various occupations and industries (Tables 5 and 6). The industry with the highest cumulative rate of eye injuries was communication (14 per 1000), followed closely by construction (13 per 1000) (Table 5), whereas the highest industry-specific cumulative rates of eye injury were recorded for tradespersons (18 per 1000), student or nonclassifiable trainees (16 per 1000), and managers and administrators (11 per 1000) (Table 6).
Discussion To our knowledge, this is the first population-based report of eye injuries in Australia, and the data are important for public health education. We found eye injuries requiring doctor’s treatment to be a significant public health problem, with more than 20% of Victorians aged 40 and over having had at least one eye injury during their lifetime. Our overall rate of 34% in men is substantially higher than the rate of 20% reported in white men in the Baltimore Eye Survey, although our rate of 9.9% in women is comparable to the reported rate of 7.7% in white females in that study.8 Researchers in the Baltimore Eye Survey noted a decrease
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in ocular injuries in the older age groups similar to the decrease that we observed in the Visual Impairment Project. There are several potential explanations for this observed decrease. First, older people might truly have experienced less ocular trauma during their lifetimes owing to decreased exposure to high-risk situations. Second, a systematic recall bias may exist in this cohort about injuries that occurred when the respondents were younger such that they are not recalled. Third, a survivor bias could exist in this cohort, where people who experienced eye injuries during their lifetime are at greater risk of mortality and therefore have not survived long enough to participate in our study. Although the incidence of eye injuries has been shown to decrease with age, the average annual hospital discharge rate for ocular trauma has been shown to increase dramatically after the age of 80 years.5 This increased rate of hospitalization in the elderly could be due to falls leading to more serious injuries in this age group. Not only was the lifetime prevalence of eye injuries higher in the Visual Impairment Project than the Baltimore Eye Survey,8 but also the estimated annual incidence was higher (11.4 per 1000 compared with 4.1 in white men and 1.8 in white women). This compares to the expected number of eye injuries requiring medical attention in 1985 per 1000 New England adults, which ranged from 4.1 in Rhode Island to 15.3 in New Hampshire.3 The difference between the states could be due to different age structures and occupations associated with ocular trauma. In the state of Victoria, the estimated annual incidence rate translates to 9755 eye injuries serious enough to require medical attention in people aged 40 and over each year based on 1996 census figures. A study conducted at the Royal Victorian Eye and Ear Hospital from 1989 –1991 estimated that 31,000 Victorians of all ages sustain eye injuries annually at a cost of $37 million (Fong LP, MD
McCarty et al 䡠 Ocular Trauma in Australia Table 4. Eye Protection Worn at the Time of Injury Type of Eye Protection Worn None Protective spectacles* Safety goggles* Shield* Ordinary spectacles Sunglasses Contact lenses
No. (%) 1224 (87) 58 (4.1) 50 (3.6) 35 (2.5) 30 (2.1) 4 (0.3) 3 (0.2)
* Correct protective eyewear.
thesis, University of Melbourne, 1995), which means that slightly under one third of all eye injuries occur in people aged 40 years and over. In close agreement, we found in the Visual Impairment Project that 40% of all reported lifetime eye injuries occurred at age 40 years and older. This figure could be a slight overestimate owing to recall bias and the fact that details were not available for all injuries. We estimate that 488 Victorians in this age group are hospitalized annually because of their eye injuries. The workplace accounted for the majority of all injuries in the current study, and less than 20% of the workers had been wearing any form of eye protection at the time of the injury. Very similar results were found in a study of patients treated at the Royal Victorian Eye and Ear Hospital,4 in which the workplace accounted for 44% of all injuries and only 16% of all patients injured at the workplace were wearing correct protective equipment (the appropriately designed or rated protective spectacles, goggles, or shield for that particular hazardous activity), although 36% reported that they were wearing some form of protective eyewear at the time of the injury (ordinary spectacles, sunglasses).4 Researchers found that use of no or incorrect protective eyewear was particularly high for workers at home or those employed in small shops. A hospital-based study in the United States also found that approximately half of all injuries occurred at the workplace, but 66% reported wearing protective eyewear at the time of the injury.7 In the
National Eye Trauma System Registry in the United States, less than 10% of injured workers reported use of protective eyewear at the time of the injury.6 These data highlight the need for education and enforcement of regulations about the use of ocular protection in the workplace. Because 17% of people reported wearing only ordinary spectacles for eye protection at the time of their injury, it is important to educate people about the use of proper eye protection. In the current study, sports accounted for more than 5% of all eye injuries, and less than 2% of people injured while playing sports were wearing eye protection at the time of the injury. The rate of hospitalization for sports-related injury was about 10%. At the Royal Victorian Eye and Ear Hospital, sports injuries accounted for 5% of all injuries but 22% of hospital admissions and carried a high ocular morbidity.14 The most frequent sports-related eye injuries in this study were squash, Australian Rules football, indoor and outdoor cricket, and badminton. In a study of patients with sports-related ocular trauma who were treated at a tertiary care center in the United States, 14% required hospitalization and only 5% had worn eye protection at the time of the injury.15 These data indicate that playing sports is a major cause of ocular trauma, especially trauma resulting in hospitalization, and that again education is needed to encourage people to wear proper eye protection. Elite athletes should serve as role models for the use of eye protection in sports,16 and public health legislation could be considered for amateur sports as a means to increase the use of protective eyewear during all types of sports. The causes of half of all eye injuries in the current study were steel-metal, drilling-grinding-sanding, and welding; less than one third of people injured due to these causes were wearing eye protection at the time of the injury. The Royal Victorian Eye and Ear Hospital study found that tools and metal accounted for the majority (41%) of all eye injuries.8 In contrast, assault accounted for the majority (41%) of all eye injuries seen at a public medical center in Los Angeles.17 A commonly performed activity in the community is gardening, which was responsible for 10% of all injuries in this cohort; less than 10% of people injured due
Table 5. Industry-specific Cumulative Rates of Eye Injury that Occurred at Work
Industry
Cumulative No. of Eye Injuries at Work
Person-years at Risk
Cumulative Prevalence of Eye Injuries per 1000 Person-years at Risk [% (95% CL)]
Agriculture, forestry, fishing, and hunting Mining Manufacturing Electricity, gas, and water Construction Wholesale and retail trade Transport and storage Communication Finance property and business services Public administration and defense Community services Recreation, personal and other services Nonclassifiable economic units (e.g., students)
110 17 218 11 107 79 52 43 8 28 0 33 28
16389 1400 30608 1932 8420 22830 6766 3152 9478 8103 17727 27241 43787
6.7 (5.5, 8.0) 12.1 (6.4, 17.9) 7.1 (6.2, 8.1) 5.7 (2.3, 9.0) 12.7 (10.3, 15.1) 3.5 (2.7, 4.2) 7.7 (5.6, 9.8) 13.6 (9.6, 17.7) 0.8 (0.3, 1.4) 3.5 (2.2, 4.7) 0 1.2 (0.8, 1.6) 0.6 (0.4, 0.9)
CL ⫽ confidence limits.
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Ophthalmology Volume 106, Number 9, September 1999 Table 6. Occupation-specific Cumulative Rates of Eye Injury that Occurred at Work Occupation
No. of Eye Injuries at Work
Person-years at risk
Cumulative Prevalence of Eye Injuries per 1000 Person-years at Risk [% (95% CL)]
Managers and administrators Professionals Paraprofessionals Tradespersons Clerks Salespersons/personal service workers Plant and machine operators and drivers Laborers and related workers Home duties Retired Unemployed Student or nonclassifiable trainee Armed services, no specific occupation Volunteer Injured/sick/invalid Traveling/tourist/on holiday Prisoner of war Refugee/in migrant camp On paid leave
144 40 34 268 21 14 83 88 8 10 2 15 6 0 1 0 0 0 0
23,788 14,210 7447 21,573 19,772 11,823 13,192 21,882 48,384 12,641 599 1270 1500 29 694 203 69 10 2
11.4 (10.0, 12.7) 3.7 (2.7, 4.7) 6.3 (4.51, 8.09) 17.9 (16.2, 19.7) 1.4 (0.88, 1.92) 1.6 (0.88, 2.32) 9.08 (7.46, 10.7) 5.41 (4.44, 6.38) 0.24 (0.1, 0.38) 1.11 (0.53, 1.69) 3.66 (0, 8.47) 16.3 (9.3, 23.2) 5.35 (1.66, 9.02) 0 1.48 (0, 4.33) 0 0 0 0
CL ⫽ confidence limits.
to this cause were wearing eye protection at the time. Some eye injuries will inevitably remain unavoidable (such as being poked in the eye) because people do not wear eye protection at all times. Therefore, public health education efforts should be concentrated on common activities that put people at higher risk of eye injuries, including high-risk occupations such as the trades that involve hammering and welding, sports, gardening, and the use of other tools at home. In these circumstances, everyone should be encouraged to wear protective spectacles. This could reduce the incidence of eye injuries and the burden of ocular trauma and its associated costs on the community. In summary, ocular trauma continues to be an important public health problem in Victoria and Australia, affecting more than one fifth of the adult population. Similar rates and circumstances have been documented in two studies with very different methodologies, the population-based Visual Impairment Project, and the Royal Victorian Eye and Ear Hospital– based study,4 thus providing validity to both studies. Public health education is clearly warranted to raise awareness about the risk of ocular trauma and the appropriate ocular protection to prevent eye injuries, and further public health legislation should be considered where appropriate and feasible.
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4. Fong LP. Eye injuries in Victoria, Australia. Med J Aust 1995;162:64 – 8. 5. Klopfer J, Tielsch JM, Vitale S, et al. Ocular trauma in the United States. Eye injuries resulting in hospitalization, 1984 through 1987. Arch Ophthalmol 1992;110:838 – 42. 6. Dannenberg AL, Parver LM, Brechner RJ, Khoo L. Penetration eye injuries in the workplace. The National Eye Trauma System Registry. Arch Ophthalmol 1992;110:843– 8. 7. Schein OD, Hibberd PL, Shingleton BJ, et al. The spectrum and burden of ocular injury. Ophthalmology 1988;95:300 –5. 8. Katz J, Tielsch JM. Lifetime prevalence of ocular injuries from the Baltimore Eye Survey. Arch Ophthalmol 1993;111: 1564 – 8. 9. Livingston PM, Carson CA, Stanislavsky YL, et al. Methods for a population-based study of eye disease: the Melbourne Visual Impairment Project. Ophthalmic Epidemiol 1994;1: 139 – 48. 10. Australian Bureau of Statistics. 1996 Census of Population and Housing. Canberra: ABS; 1997. 11. Cochran WG. Sampling Techniques, 3rd ed. New York: Wiley, 1977. (Wiley Series in probability and mathematical statistics; A Wiley publication in applied statistics). 12. Statistical Methods in Cancer Research. Vol. II. Lyon: International Agency for Research on Cancer, 1989; p 58 – 61. 13. Livingston PM, Lee SE, McCarty CA, Taylor HR. A comparison of participants with non-participants in a populationbased epidemiologic study: the Melbourne Visual Impairment Project. Ophthalmic Epidemiol 1997;4:73– 81. 14. Fong LP. Sports-related eye injuries. Med J Aust 1994;160: 743–50. 15. Larrison WI, Hersh PS, Kunzweiler T, Shingleton BJ. Sportsrelated ocular trauma. Ophthalmology 1990;97:1265–9. 16. Vinger PF. The incidence of eye injuries in sports. Int Ophthalmol Clin 1981;21:21– 46. 17. Liggett PE, Pince KJ, Barlow W, et al. Ocular trauma in an urban population. Review of 1132 cases. Ophthalmology 1990;97:581– 4.