Hearing Loss - Supplemental Activity 5: Cost Tool - Student's Worksheet
Cost Analysis Tool Applied to Sound Advice Throughout the Years
PARTNERSHIPS FOR PREVENTING FARM INJURIES TO RURAL YOUTH
Objectives:
Academic Expectation 2.18: Students understand economic principles and are able to make economic decisions that have consequences in daily living. (Grade 11)
1. The basic economic problem confronting individuals and societies is the scarcity or imbalance between unlimited wants and limited resources available for satisfying those wants.
Microsoft Excel™ Spreadsheet: Low Road. Sound Advice throughout the Years1
Exercise1 : Review of the cost of Heather’s fall.
WORKSHEETS
Ellen’s Care
Noise Sources
Lifetime Exposures
Percentage Exposure
Hazardous Exposures
Hearing Loss
Collateral Injuries
Intervention Cost
Glossary
Annual exposure: The amount of time per year, such as in hours, which an individual is exposed to a potential hazard over a year. An equivalent work-year has been defined as fifty 40-hour weeks per year, or 2000 hours of work per year. Benefit: Something of positive value. Cost (of inputs): Price paid or loss incurred to acquire or produce something. Decibel: A unit of relative sound loudness as measured by an electric voltage, or current, equal to ten times the common logarithm of the ratio of two sound readings. Direct costs: Costs incurred to secure medical treatment and medications. Economics: Study of the choices people make and the actions they take in order to make the best use of scarce resources in meeting their wants and needs. Economies of scale: A condition that makes it less expensive to manufacturer, market, and distribute large quantities of goods than small quantities of those same goods. Indirect costs: Costs not directly associated with prevention and health care activities that accrue to individuals, society, or employers such as productivity losses. Intervention: An attempt to change how things are done in order to improve safety. Noise: Any unwanted sound or a combination of sounds. Opportunity cost: Cost of a good measured in terms of lost opportunity to pursue the best alternative activity with the same time and resources. Price: The amount of money received from a sale or for a purchase including labor. Scarcity: When there is not enough of a resource to all meet of people’s wants and needs. Social cost: The total cost to society that includes all costs no matter whom or what incurs the cost. Supply and demand: The relationship between the availability of a good or service and the need or desire for it among consumers. |
This and the next two exercises involve placing data into a spreadsheet and understanding the results of the embedded analyses of your entries. These entries progressively affect later worksheets through a total of 20 worksheets. The first worksheet is “Ellen’s Care.” Data entered into each worksheet affects the calculations of the following worksheets. Note that as we start, each worksheet is devoid of data
WORKSHEET 1—Ellen’s Care
JR ran to call an ambulance as Pete’s kneeled over Ellen’s motionless body. She may have been killed, or she may have survived. Later, JR did some calculations about the major cost of each possibility as shown in Table 1.1.
Table 1.1. Costs Associated with Ellen’s Injury with Two Possible Outcomes. |
|
IF ELLEN WAS DEAD |
IF ELLEN WAS ALIVE |
Direct Costs |
|
The emergency response bill cost $3,000. |
The emergency care including EMS and helicopter transport cost $9,200. |
The coroner service cost the county $300. |
Heather had received hospital care at a cost of $260,000. |
The funeral service expenses cost the family $12,000. |
Physician care at $50,000. |
The cemetery plot and burial expense to the family was $6,000. |
Care in later years at a cost of $236,000. |
The grave marker cost the family $2,500. |
Rehabilitation care at $254,000. |
Indirect Costs |
|
Ellen’s loss of a productive lifetime to society was $2,200,000. |
Ellen’s lifetime productivity loss because of permanent injury to her legs was $500,000. |
Pete’s hearing aids and ear operations to improve his hearing cost $6,500. |
Pete’s hearing aids and ear operations to improve his hearing cost $6,500. |
Pete went into depression the treatment fro which cost $45,000. |
The parent’s lost time in caring for Ellen meant an income loss to them of $22,000. |
Family counseling for Ellen’s parents and grandparents to cope with the guilt associated with the death cost $30,000. |
Travel mileage and meal cost of $18,380 for the family to visit and transport Ellen. |
Legal fees associated with dividing up the costs of the expenses related to Ellen’s death were $10,000. |
Pete hired labor on the farm during his and his wife’s time of help in Ellen’s recovery at a cost of $15,000. |
The cost for time lost to grieve by the family cost $30,000 in lost income to both the parents, and both sets of grandparents. |
The cost associated with Ellen’s delay in attending school and accommodations related to her education was $200,000. |
Choose one of these two conditions on Worksheet 1, Ellen’s Care by clicking the checkbox. The cost values in Table 1.1 will be automatically entered in the spreadsheet.
QUESTION 1.1. What was the total cost of Ellen’s injury?
If she was dead? ________________
If she was alive? ________________
WORKSHEET 2—Noise Sources
JR knew that his shotgun was louder than his chainsaw. He did some research on the Internet and found that noise (unwanted sound) was measured with a noise meter, and the noise meter measured sound with a unit called a decibel. The decibel measured the amount of energy in sound, but the increase in energy increased three times (the vibrations on the eardrum) for each increase in three decibels.
JR found the decibel levels for several different sources of noise on the Internet.
JR found that the average exposure over an 8-hour period should not exceed 85 decibels (dB) to prevent hearing loss from noise.
QUESTION 1.2. Is Pete's average 8-hour exposure above the noise hazard limit?
_______
WORKSHEET 3—Lifetime Exposures
Based upon his knowledge of Pete’s lifetime exposure to different noise sources, JR calculated the hours of exposure as shown in Table 1.2.
Table 1.2. Hours of Pete’s Lifetime Exposure to Different Noise Sources. |
|
Noise Source |
Number of Hours Exposed |
Tractor |
28,670 |
Chainsaw |
1,826 |
Combine |
5,549 |
Grain dryer |
7,117 |
Other agricultural sources |
12,188 |
Other occupational sources (non-farm) |
24,650 |
Hunting and target shooting |
2,459 |
Motorcycle and snowmobile riding |
2,616 |
Rock band |
1,210 |
Other non-occupational sources |
5,646 |
QUESTION 1.3. To which noise source was Pete exposed to for most of his lifetime?
_____________
WORKSHEET 4—Percentage Exposure
Look at JR’s pie chart on WORKSHEET 4—Percentage Exposure.
QUESTION 1.4. Which source of noise was greater to Pete, occupational or non-occupational?
______________
WORKSHEET 5—Hazardous Exposures
JR found the following scale of permissible noise exposure. As he already knew, hearing would be protected at no more than an 85 decibel (dB) exposure over an 8-hour period. He was surprised to see that an increase in noise exposure from 3 decibels to 88 decibels for more than 4 hours will damage hearing.
JR listed the information on noise sources and the typical 8-hour exposure to these sources as shown on WORKSHEET 5—Hazardous Exposures.
QUESTION 1.5. Based upon the standards shown above, mark each exposure which is hazardous to hearing?
□ chainsaw
□ combine
□ grain dryer
□ other agricultural
□ other occupational
□ 8-hour average
□ hunting and target shooting
□ motorcycle and snowmobile riding
□ rock band
JR found a chart that he could change by scrolling a bar on the computer to determine hearing loss based upon years of exposure to a lot of noise.
When his hearing loss reached 25 decibels his hearing disability of 0% began, and then over time it moved up towards a 75 decibel hearing loss at which there would be a 100% hearing disability.
QUESTION 1.6. How many years of exposure first led to a hearing loss of 25 decibels?
______________
WORKSHEET 7—Collateral Injuries
An injury occurred as a result of Pete’s hearing loss. JR found that hearing loss does lead to an increase in occupational injuries. He found hearing loss can increase injuries by a percentage of 37%.
QUESTION 1.7. How many injuries (per (100) would be prevented if the person had no hearing loss?
_________ injuries per 100 workers.
WORKSHEET 8—Intervention Cost
JR was very familiar with the cost of ear plugs needed to protect his ears from noise exposure. He knew that the law of supply and demand applied to ear plugs. As the demand increases the price of ear plugs drops because it costs less to supply a larger quantity than a smaller quantity of ear plugs. This is an example of economies of scale.
One choice was to buy the ear plugs at the local drug store in packages of 10 for $2.50, or a cost of $0.25 per pair.
Another choice was to buy the ear plugs at a Big Box store in packages of 50 for $7.50, or a cost of $0.15 per pair.
A third choice was to buy the ear plugs on the Internet in packages of 150 for $10.50, or a cost of $0.07 per pair.
QUESTION 1.8. What is the cheapest cost per year for ear plugs?
_____
Exercise 2: Decision analysis for making the Pete’s actions safer.
WORKSHEETS
Exposure (Hours)
Ear Plug Effectiveness
Probabilities
Glossary Disability: A physical or mental impairment that substantially limits one or more major life activities. Decision analysis: An explicit, quantitative, systematic approach to decision making under conditions of uncertainty. Loss control: The economics of safeguarding against injury to people or damage to property. Probability: A number between 0 and 1, and the sum of the probabilities that the event will occur and that it will not occur is 1. |
WORKSHEET 9—Exposure Hours
JR found that for the general agricultural population that 10% of farmers experienced hearing loss similar to Pete’s loss of hearing. He related the hours of exposures to loud noise as 10% of the work day for farmers.
QUESTION 2.1. What percentage of the work day does hearing loss occur?
______
WORKSHEET 10—Ear Plug Effectiveness
Manufacturers give ear plugs an effectiveness rating for the number of decibels that the plugs reduce the noise to the ear. However, a safety factor is used since error may exist in fitting the plugs into the ear. The safety factor compensates for the error. All of the earplugs that JR used were rated for a 33 dB reduction.
QUESTION 2.2. For which noise source is ear plugs least effective?
____________
WORKSHEET 11—Probabilities
Hearing impairment adds to the risk of injury. The risk of work-related death of hearing impaired workers is 0.073% per 100 workers per year. The risk of occupational (nonfatal) injury of hearing impaired workers is 6.2% per 100 workers per year.
QUESTION 2.3. How does the potential for “injury” change when a farmer has good hearing? Does it increase or decrease?
_____________
Exercise 3: Cost analysis for making the Pete’s actions safer.
WORKSHEETS
Injury Schedule and Inflation
Noise Schedule
Cost Effectiveness Analysis
Glossary Expected Cost (Value): The mean (weighted average) of a variable. Inflation: A sustained increase in the average price of all goods and services because of an increase in currency. Productivity: A relation between input and output. Entrepreneur: An individual looking for new possibilities: making use of new ways of doing things, being alert to new opportunities, and overcoming old limits. Market: Any arrangement that people have for trading with one another. Cost analysis: The process of estimating the cost of prevention activities. Cost effective: Comparison of alternative interventions (including no interventions) per health outcome achieved and is presented as cost per injury case prevented. Cost-effectiveness analysis: An economic analysis in which all costs and benefits (negative costs) are related to a single, common effect. Time (analytic) horizon: The period of time that the effect of the intervention extends into the future, such as the length of time that the injury would have a potential impact, or the potential number of years that the tractor would be used. |
Various types of cost analyses can be used to compare one alterative to another. In this exercise, the primary focus is on cost-effectiveness analysis. These analyses by JR build on his previous results of potential injuries and noise induced hearing loss averted.
WORKSHEET 12—Injury Schedule and Inflation
Injuries related to noise-induced hearing loss has been established. The costs for these injuries by their severity (outcome) and type (direct and indirect cost) are shown in Table 3.1.
Table 3.1. Cost of injury related to noise induced hearing loss |
||
Outcome |
Type |
Injury Cost (1997 data) |
Death |
Direct |
$33,850 |
Death |
Indirect |
$682,586 |
Nonfatal |
Direct |
$8,819 |
Nonfatal |
Indirect |
$25,028 |
Any cost data taken from the past must be adjusted for inflation between when that data was created and its current money value.
QUESTION 3.1. Observe the chart. What effect does inflation have on these costs? Do the costs inflate over time?
_______
WORKSHEET 13—Noise Schedule and Inflation
Noise-induced hearing loss also has lifelong effects upon its victim. These effects include direct costs associated with hearing loss including both medical and non-medical costs. They also include indirect cost associated with productivity losses. These effects and associated costs are shown in Table 3.2.
Table 3.1. Cost of noise induced hearing loss |
||
Cost Factor |
Cost (2000 data) |
|
Direct Medical
|
Physician Visits |
$8,129 |
Medications |
$106 |
|
Hospital Inpatient Stays |
$8,683 |
|
Assistive Devices |
$5,438 |
|
Therapy/Rehabilitation | $735 | |
Direct Non-medical
|
Home/Auto Modifications |
$678 |
Special Education |
$66,690 |
|
Productivity Losses
|
Disability |
$224,109 |
Premature Death |
$11,170 |
Any cost data taken from the past must be adjusted for inflation between when that data was created and its current money value.
QUESTION 3.2. Which of the three major lifetime categories is the most costly?
____________________
WORKSHEET 18—Cost Effectiveness
Noise-induced hearing loss accumulates over the years. On this worksheet a noise exposure from age 17 to 24 years reduced hearing by 25 dB. This is the point at which a hearing disability begins. As noise exposure continues through the years, the hearing disability and its associated costs increase.
QUESTION 3.3. Are the NET COST results a cost or a savings?
_________________
References
CDC. A practical guide to prevention effectiveness: decision and economic analyses. Prepared by the Prevention Effectiveness Activity, Epidemiology Program Office, Centers for Disease Control and Prevention, Atlanta, Georgia.1994.
Choi SW, Peek-Asa C, Sprince NL, Rautianen RH, Donham KJ, Flamme GA, Whitten PS, Zwerling C. 2005. Hearing loss as a risk factor for agricultural injuries. Am J Indust Med. Accepted 11 July 2005.
Depczynski J, Franklin RC, Challinor, Williams W, Fragar LJ. 2005. Farm noise emissions during common agricultural activities. J Agric Safety Health. 11(3):325-334.
Dolan EG. 1983. Micro-economics. New York: Dryden Press.
Gold MR, Siegel JE, Russell LB, Weinstein MC. 1996. Cost-effectiveness in health and medicine. New York: Oxford University Press.
Haddix AC, Teutsch SM, Shaffer PA, et al (eds.). Prevention Effectiveness: A Guide to Decision Analysis and Economic Evaluation. New York: Oxford University Press. 1996:103-129.
Honeycutt AA, Grosse SD, Dunlap LJ, Schendel DE, Chen H, Brann E, al Homsi G. 2003. Economic cost of mental retardation, cerebral palsy, hearing loss, and vision impairment. Research in Social Science and Disability. 3(207-228.
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Lupescu C, Angelstad B, Lockinger L, McDuffie HH, Hagel LM, Dosman JA, Bidwell J. Hearing conservation program for farm families: an evaluation. J Agric Safety Health. 5(3):329-337.
Petitti DB. Meta-Analysis, Decision Analysis, and Cost-Effectiveness Analysis: Methods for Quantitative Synthesis in Medicine. New York: Oxford University Press. 1994:24-28.
Prince MM, Stayner LT, Smith RJ, Gilbert SJ. 1997. A re-examination of risk estimates from the NIOSH Occupational Noise ad Hearing Survey (ONHS). J Acoust Soc Am. 101(2):950-963.
Reilly MJ. Rosenman KD, Kalinowski DJ. 1998. Occupational noise-induced hearing loss surveillance in Michigan. J Occup Envir Med. 40(8):667-674.
Riggs JL. 1977. Engineering economics. New York: McGraw-Hill Book Company.
Tormoeblem R, Field W. 1995. Projecting economic losses associated with farm-related disabilities. J Agric Safety Health. 1(1):27-36.
Walkenbach J. 2003. Excel 2003 Bible. Indianapolis, IN: Wiley. Publishing, Inc.
Wilkins JR, Engelhardt HL, Crawford JM, Mitchell GL, Eicher LC, Bean TL, Jones LA. 1998. Self-reported noise exposure among Ohio cash grain farmers. J Agric Safety Health. Special Issue 1:79-88.
Zwerling C, Whitten PS, Davis CS, Sprince NL. 1998. Risk of injury among workers with disability.JAMA. 279(17):1348-1350.
1 This version of the Cost Analysis Tool has excluded certain concepts so that other concepts could be taught under the time constraints for teaching in high school. Because of their complexity, concepts excluded were discounting, present value, decision tree, sensitivity analysis, break-even analysis, exposure hours, and some applications of probabilities.
This curriculum guide was supported by Grant Number 1 R01/CCR414307 from NIOSH. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of NIOSH. Special thanks to Dr. Ted Scharf.
Disclaimer and Reproduction Information: Information in NASD does not represent NIOSH policy. Information included in NASD appears by permission of the author and/or copyright holder. More