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Costs of Injuries Resulting from Motorcycle Crashes:
A Literature Review
Appendix E
Summary and Review Standards for Motorcycle Crash Cost Studies

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Study population
Data & methods

Topics for Review:
Injury Cost Questions

Costs of motorcycle crashes and injuries

External costs (costs not borne by motorcyclist)
of riding unhelmeted

Motorcyclist injury profile

Effects of helmet use

Who pays the medical costs of motorcycle crash victims?

How do prevention measures affect costs and outcomes?

Methodological Issues

1. How does article treat riders who are helmeted, unhelmeted, and helmet-use- unknown?

2. Costs, charges, payments

a. How were costs computed?

b. Did payments include only third- party payments, or also deductibles and co-payments?

c. What payers are included? (Reimbursement rates differ.)

d. If multiple years of data were used, were costs adjusted to the same year’s dollars?

3. When was payer recorded -- at admis sion or discharge?

4. Payer shares -- percent of admissions, percent of days in hospital, or percent of payments?

5. Study population

a. Survivors and fatalities separated?

b. Non-admitted survivors captured?

c. Representative sample of motorcyclists? (e.g., trauma center patients are not representative of the larger population of motorcycle injury victims)

6. Studies that compare groups must con trol for potential differences between groups in:

a. Exposure (VMT, number of motorcycles, number of riders)

b. Years riding

c. Purpose of riding (commuting vs. recreation)

d. Age

e Self-selection (helmet-wearers may be more risk-averse)

7. Design and statistical technique -- look for misleading comparisons

a. Comparisons between percentages of injured motorcyclists with and without helmets, which do not acknowledge differences in injury percentages

b. If crash data linked to admissions data, pre-admission fatalities must be accounted for when computing admission rates

c. Comparison of payers between groups must consider age differ ences between populations


Methodological strengths and weaknesses

• Distinguish minor weaknesses from major flaws

Assess whether conclusions are merited

• Present corrected conclusions (if necessary)

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