Monash University Accident Research Centre Report #124 - 1997
Authors: W. Watson & J. Ozanne-Smith
Full report in .pdf format [483 KB]
Injury has been identified as a major public health problem in Australia and internationally. It is the leading cause of death of persons aged between 1 and 44 years, accounting for up to 72% of deaths in some age groups (eg. 15-24 years). The cost of injury also imposes an enormous burden on the community in Australia with a 1986 figure of $11 billion per year still quoted as the best available estimate.
The aim of this study is to broadly describe the epidemiology of injury in the State of Victoria at all levels of severity and to provide an estimate of the total lifetime cost of injury to the Victorian community for cases incident in a given year.
The incidence of both unintentional and intentional injury in Victoria in 1993/94 was directly derived, or estimated from, the available Victorian health sector and Coronial data bases for three level of severity : deaths, hospitalisations and medical treatment only. Incidence was also established for the different causes of injury, age- and gender groups, location of the injury event and activity being undertaken at the time of injury.
In 1993/94, injuries resulted in at least 1,487 deaths (with an estimated 142 deaths occurring in later years as a result of injuries sustained in that year), 67,402 persons hospitalised, and an estimated 397,160 medically-treated non-hospitalised injured persons in Victoria in 1993/94. In total, over 466,000 people were injured or 10.5 persons injured per year for every 100 Victorian residents.
Average treatment costs for each level of injury severity were provided by the States injury compensation schemes, the Transport Accident Commission and the Victorian WorkCover Authority. A matrix, based on nature of injury by body part, was also developed, in conjunction with the Victorian WorkCover Authority, to allow more specific allocation of direct costs to the various injury cause and age categories for hospitalised cases (hospitalised cases accounting for the major part of treatment costs). Indirect costs were estimated using the human capital method.
The total lifetime cost of injury sustained in 1993/94, in Victoria, is $2,583 million, consisting of direct costs of $759 million, plus indirect costs including mortality costs of $813 million and morbidity costs of $1,010.5 million.
This study broadly describes the epidemiology of injury in the State of Victoria at various levels of severity and provides an estimate of the total lifetime cost of injury to the Victorian community for cases which occurred in the financial year 1993/94, the most recent year for which reliable incidence data for each level of injury severity were available.
Fundamental to developing estimates of the economic cost of injury are data on incidence. Estimates of the numbers and rates of injury are presented in this report for three mutually exclusive groups that broadly reflect the severity of injury : (1) injury resulting in death, (2) injury resulting in hospitalisation with survival to discharge, and (3) injury requiring medical attention without hospitalisation. Incidence was also established for the different causes of injury, age and gender groups, location of the injury event and activity being undertaken at the time of injury. Because important segments such as sporting, home and workplace injuries are concealed by the ICD-9 classification by cause, incidence estimates for each level of injury severity were also developed for the settings in which injury events occur and the activity being undertaken at the time of injury.
The major data sources used in estimating the number of injuries that occurred in Victoria in 1993/94 were the Victorian Coroners Facilitation System (VCFS) for deaths, the Victorian Inpatient Minimum Dataset (VIMD) for live hospital discharges and the Victorian Emergency Minimum Dataset (VEMD) and the Extended Latrobe Valley Injury Surveillance (ELVIS) for less severe, non-hospitalised injuries. Injuries for which medical attention was not sought at either a hospital Emergency Department or a general practice have not been included since there is no data currently available on the frequency of such cases. This will result in an underestimation of both the incidence of injury and the costs.
The total lifetime cost of injury estimated in this study consists of costs relating to the treatment of injury (direct costs) and costs relating to the loss, or partial loss, to society of the productive efforts (both paid and unpaid) of injury victims and care-givers in the case of children (indirect costs).
Direct or treatment costs are the actual expenditure related to the injury and include medical and non-medical costs such as hospital (inpatient and Emergency Department), medical (general & specialist services) and rehabilitation (rehabilitation services, aids and equipment) costs associated with the treatment of injury. Other direct costs include ambulance transport, pharmaceuticals and treatment by health professionals other than medical doctors.
Average treatment costs for each level of injury severity were provided by the States injury compensation schemes, the Transport Accident Commission and the Victorian WorkCover Authority. A matrix, based on nature of injury by body part, was also developed, in conjunction with the Victorian WorkCover Authority, to allow more specific allocation of direct costs to the various injury cause and age categories for hospitalised cases (hospitalised cases accounting for the major part of treatment costs).
Indirect costs represent the value of lost output due to reduced productivity caused by injury and any resultant disability (morbidity) and losses due to premature death (mortality). Loss or partial loss of future production has been estimated in terms of earnings and labour on-costs of injury victims, the productive but unpaid contribution of victims to their households and communities and the productive time lost by care-givers of child injury victims.
Indirect costs were estimated using the ex-post human capital method by assigning an economic value to the loss of life and productive capacity resulting from injury, following the work of Rice et al. (1989) and the Bureau of Transport and Communication Economics (BTCE, 1992). In contrast to the BTCE (1992), which used the accident as the basic costing unit, in this study the basic costing unit is the injured person.
Since the willingness-to-pay approach to valuing indirect cost is becoming more common, estimates of this cost in relation to injury in Victoria (based on overseas estimates of the value of life and non-fatal injuries), were also developed for reference purposes.
OVERVIEW OF RESULTS
In 1993/94, injuries resulted in at least 1,487 deaths (with an estimated 142 deaths occurring in later years as a result of injuries sustained in that year), 67,402 persons hospitalised, and an estimated 397,160 medically-treated non-hospitalised injured persons in Victoria. In total, over 466,000 people were injured or 10.5 persons injured per year for every 100 Victorian residents. Just over one in 10 persons in this State, in a year, sustain an injury that requires at least an attendance at a hospital Emergency Department or a general practitioners surgery. Many of these injuries are fatal or serious enough to require hospitalisation and are associated with long-term disability.
Of the total 466,049 persons injured, almost 30 percent (134,543) were in the 25-44 year age-group (who account for 31 percent of the Victorian population). Persons aged 15-24 comprise almost 16 percent of the Victorian population yet account for more than 20 percent (103,704) of all injuries. While children under the age of 15 account for 21 percent of the total Victorian population, they comprise almost 30 percent of the total injured population (about 131,500 injuries). Overall, persons aged under 45 years sustain almost 80 percent of all injuries.
The risk of injury is higher among males who sustain almost 62 percent of all injuries yet account for only 49.5 percent of the population. Almost 13 percent of Victorian males incur injuries, whereas for females the risk is lower with about 8 percent sustaining an injury in a year. Among both males and females the largest number of injuries occurs in the 25-44 year age-group. The risk of injury is highest, however, for younger males with more than one in five (or 20 percent of) males aged 15-24 sustaining an injury during a single year. Overall, the leading cause of injury death in Victoria is suicide, followed by motor vehicle accidents, whereas falls are the leading cause of hospitalisation and of all non-fatal injury.
Most injuries occur in the home (36 percent) followed by areas of sport and recreation (12.5 percent) then transport (11.7 percent). In terms of activity being undertaken at the time of injury, most injuries were associated with sport and leisure activities (40.2 percent) followed by work-related injury (11 percent) then transportation injuries (10.8 percent).
The total lifetime cost of injury for persons who sought medical treatment for injury in Victoria in 1993/94, is estimated at $2,582.9 million, or an average of $5,541 per injured person. Direct expenditure for treatment of injury including hospital, medical, pharmaceuticals, rehabilitation, attendant and nursing home care and other services amount to almost $759 million or $1,628 per injured person. (Note that average costs are skewed towards the cost of non-hospitalised injury due to the large number of cases in this category).
Disability from injury results in loss of output with individuals generally, unable to attend to their normal activities (eg domestic duties), and members of the labour force, unable to work. In total more than 59,000 life-years (to age 75) are lost (46.5 days per injured person) as a result of injuries sustained in 1993/94, valued at $1,010.5 million. The morbidity cost amounts to an average of $2,175 per injured person.
Other losses result from premature injury fatalities. At least 1,487 premature deaths from injury occurred in 1993/94, with an estimated additional 142 deaths occurring in later years as a result of injury sustained in 1993/94. Premature death from injury amounted to an estimated annual loss of 48,773 life years (to age 75), or 30 years per death. The mortality cost amounted to $813.5 million, or an average cost of $499,378 per death.
In terms of cause, the greatest losses are due to motor vehicles traffic accidents and falls, accounting for $570.5 million and $557.2 million respectively. Although the injury rate for falls is higher than for motor vehicle accidents, the significantly higher number of motor vehicle fatalities among young people results in higher lifetime costs. Motor vehicle traffic injuries account for 7 percent of all injuries and 22 percent of total economic costs whereas falls account for almost 28 percent of injuries and 21.5 percent of total lifetime costs. Self-inflicted injury ranks third in economic cost, amounting to $428.4 million, or 16.5 percent of the total cost. Although self-inflicted injury accounts for only 1.8 percent of all injuries, fatalities at young ages are high (the suicide rate is highest in the 15-24 year-old age-group), resulting in high costs.
It is clear from the results of this study that injuries have a significant impact on the Victorian community, health care system and economy in general. The impact of disability due to injury on the individual and his/her family can be personally and economically devastating. All sectors of the Victorian economy share this burden, including federal, state and local governments, the private sector and individuals. In addition to the reduction in injured person-based costs identified in this study, effective injury prevention measures would also provide savings in non-person based costs of injury events such as property damage, fire, police and judicial services, etc.
While other factors, particularly preventability, must also be taken into consideration in determining priorities for injury prevention, this study identifies the following groups as over-represented in epidemiological or cost terms :
- Suicide is the leading cause of injury death in Victoria followed by motor vehicle traffic accidents. As such these two causes also account for the highest mortality costs.
- Falls are the leading cause of non-fatal injury in Victoria. They also account for the highest total direct treatment costs and highest overall morbidity costs.
- Males are over-represented in epidemiological terms. While they represent 49.5 percent of the population, they sustain 62 percent of all injuries. Almost three-quarters of injury fatalities and over 60 percent of non-fatal injuries occur among males.
- Young people aged 15-24 years are over-represented in both epidemiological and cost terms. This age-group accounts for 22 percent of all injuries and almost 28 percent of the total lifetime cost, yet represents around 16 percent of the Victorian population. Persons in this age-group also have the highest per person mortality costs averaging $813,286 per death.
- Adults aged 25-44 are over-represented in terms of cost. Although this age-group represents 31 percent of the total Victorian population and accounts for a similar percentage of all injuries (29 percent), persons aged 25-44 years account for 37 percent of the total lifetime costs of injury.
- Drowning/near-drowning have the highest average lifetime cost at $61,866 per person followed by suicide/self-harm at $51,540 per person.
- Elderly persons over the age of 75 years have the highest direct treatment costs averaging $5,048 per injured person. This is due mainly to the high number of falls suffered in this age group.
- Most injuries, at all levels of severity, occur in the home.
- In terms of activity, sports and leisure activities are responsible for the greatest number of non-fatal injuries.
Recommendations have emerged from this study for the prevention and control of injury in Victoria.
- It is clear that, in terms of cost alone, injury is responsible for an enormous burden to the state of Victoria. It is recommended that more resources be directed towards the prevention of injuries and the reduction of their effects through the application of existing knowledge and the development and evaluation of new strategies.
- It is recommended that research and controlled experiments be conducted to evaluate the effectiveness and cost savings of a range of injury control interventions and that programs are shown to be cost-effective be implemented.
- There is evidence for the effectiveness of a number of injury prevention strategies. It is recommended that research be conducted to evaluate the economic and/or societal barriers to the application of such strategies.
Several other recommendations are made regarding data issues and further research into the epidemiology and cost of injury that supports the development of priorities and the prevention of injuries in Victoria.
This project was funded by the Department of Human Services, Victoria