Page 41 - Statistics for Dummies

Comprehending crashes
Next in the paper was an alert about the soaring number of motorcycle fatali-
ties. Experts said that the fatality rate — the number of fatalities per 100,000 reg-
istered vehicles — for motorcyclists has been steadily increasing, as reported
by the National Highway Traffic Safety Administration (NHTSA). In the article,
many possible causes for the increased motorcycle death rate are discussed,
including age, gender, size of engine, whether the driver had a license, alcohol
use, and state helmet laws (or lack thereof). The report is very comprehensive,
showing various tables and graphs with the following titles:
✓ Motorcyclists killed and injured, and fatality and injury rates by year, per
number of registered vehicles, and per millions of vehicle miles traveled
✓ Motorcycle rider fatalities by state, helmet use, and blood alcohol content
✓ Occupant fatality rates by vehicle type (motorcycles, passenger cars,
light trucks), per 10,000 registered vehicles and per 100 million vehicle
miles traveled Chapter 2: The Statistics of Everyday Life 25
✓ Motorcyclist fatalities by age group
✓ Motorcyclist fatalities by engine size (displacement)
✓ Previous driving records of drivers involved in fatal traffic crashes by
type of vehicle (including previous crashes, DUI convictions, speeding
convictions, and license suspensions and revocations)
✓ Percentage of alcohol-impaired motorcycle riders killed in traffic crashes
by time of day, for single-vehicle, multiple-vehicle, and total crashes
This article is very informative and provides a wealth of detailed information
regarding motorcycle fatalities and injuries in the U.S. However, the onslaught
of so many tables, graphs, rates, numbers, and conclusions can be overwhelm-
ing and confusing and allow you to miss the big picture. With a little practice,
and help from Part II, you’ll be better able to sort out graphs, tables, and charts
and all the statistics that go along with them. For example, some important sta-
tistical issues come up when you see rates versus counts (such as death rates
versus number of deaths). As I address in Chapter 3, counts can give you mis-
leading information if they’re used when rates would be more appropriate.
Mulling malpractice

Further along in the newspaper was a report about a recent medical mal-
practice insurance study: Malpractice cases affect people in terms of the fees
doctors charge and the ability to get the healthcare they need. The article
indicates that 1 in 5 Georgia doctors have stopped doing risky procedures

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