Environmental Approaches to Injury Prevention

Susan P. Baker, MPH

Johns Hopkins Center for Injury Research and Policy

Unintentional and Intentional Injury• Common approaches are often

appropriate regardless of intent :

– shootings: personalized weapons would prevent some injuries regardless of intent

– poisonings: the reduced carbon monoxide content of cooking gas lowered both unintentional and suicidal death rates

Passive (automatic) protection is needed because those at greatest risk of injury are:

• Young children• Teenage males• Elderly people• Intoxicated people

• Namely, the people whose behavior is hardest to change.

• Unintentional Poisoning Death Rates from Carbon Monoxide, U.S. 1947-79 –

• The period when states gradually converted to non-poisonous natural gas – an example of passive protection and its effects.

0

10

20

30

40

50

60

70

80

1947 52 57 62 67 72 77

Deaths/100,000

Correlation Between Hazardous Driving and Self-

protectionLESS SEATBELT USE IF:

• High speed• High risk situations

– following too closely– running red lights

• Nighttime

• Young drivers• Alcohol-impaired drivers

People take risks because of

• Economic pressure • Productivity pressure• Competition pressure• Peer pressure• Time pressure

They will often choose speed and convenience.

The safest way must be the easiest way,or people will make a hazardous choice.

These Sri Lankans are crossingthe river using the safe walkwaybecause it is easier than fightingthe traffic.

Photo by SP Baker

Injuries Among the Hopi Indians

Simpson et al. JAMA 249:1873-76, 1983

• Population based study; all Hopis treated in the two relevant IHS hospitals– The authors read the hospital discharge records– Visited homes, villages to examine setting

• Circumstances that were revealed– Falls from roofs– Hangings in jail– Kids falling from pickup trucks– Single-vehicle crashes – narrow, winding steep

roads without shoulders or guardrails

The hazardous environment of a Hopi village.

Baltimore’s beautiful Harborplace. The white areas between these bricks are just for decoration.

Photo by SP Baker

Nearby, similar white areas marka change in level.

What happens if someone is looking upward?

Photo by SP Baker

As I puzzled over how best to illustrate the hazard,I heard a sudden cry.

Photo by SP Baker

Residential facilities for the elderly are an environment

where there are an exceptional number of high-

risk people needing protection

The water temp atthis retirement homewas 180 degrees – hot enough to poach eggs.

Photo by SP Baker

Photo by SP Baker

The cabinets were so highthat someone would needto stand on a chair orstepstool to reach them.

The sharp corner of the hood over the stove was at eye level

Photo by SP Baker

After her forehead healed, she put thebandaid on the sharp corner in case she hit it again.

Photo by SP Baker

She was 92 years old, and like most seniors did not lift her feet highwith each step.

If she were to trip, there was no railing and the surface washard cement.

To call attention to the tripping hazard, a WHITE stripe -- unlikely to be noticed by anyone with poor eyesight.

Photo by SP Baker

One of these heldglue, the other hadeyedrops. Somepeople who needed eyedrops did not see well. Some glued their eyelids shut.

The glue manu-facturers shouldhave predicted thatand used anothershape.

Deaths in Housefires

• The leading cause of injury death among children in some cities.

• Often they are ignited by smoldering cigarettes (cigarettes can be designed to reduce the likelihood that they will ignite fabric)

55 Housefire Deaths in Baltimore

Record Review Showed:.

• 31 (56%) in cigarette-ignited fires

• 12/31 (39%) not the smokers of the cigarettes

• BAC =>.10% in half of cigarette-ignited fires

• Highest rates were in low-income areas

Mierley and Baker, JAMA 249:1466-8,1983

40 Fatal Housefires in Baltimorevs. Median Rental Value Quintile

EXPECTED OBSERVED

QUINTILE

1 8 10

2 8 13

3 8 8

4 8 5

5 8 3

Mierley and Baker, JAMA 249:1466-8,1983

The sign is hard to read from ground level.

Photo by AJ Saah

Even if it could be read, this might notdiscourage a young climber…

Photo by AJ Saah

...especially one inspired bynearby climbingequipment.

Photo by AJ Saah

Photo by SP Teret

OSHA might requiresomeone working at this height tohave some formof protection.

We just say “Be careful, Timmy,and don’t push.”

Photo by SP Baker

This slide is built into a hill. It is steep enough to givea child a good ride, but even a fall from the top is notlikely to cause injury.

Walkers place toddlers at high risk of falls down stairs. Here’s a low-risk alternative.

Photo by SP Baker

Pacifiers like the one at left were small enough to enter a child’s airway. CPSC eventually banned them.

Some foods place children at high risk of choking.

Photo by SP Baker

Foods that Caused Death of U.S. Children

• 17 hot dogs/sausages

• 9 peanuts/nuts

• 8 grapes

• 6 carrots

• 4 beans

• 4 hard candies

Harris, Baker et al JAMA 251:2231-2235, 1984.

Characteristics of FoodsLikely to Cause Fatal Choking

• Smooth

• Hard or tough

• Small

–Airway-sized

• Round

• Pliable

• Cohesive

If the water is >120 Fand mom has to answerthe phone, disaster can result.

Effectiveness varies inversely with frequency or amount of efforte.g. - To Protect A Child From Scalding

ResultingProtection

MAX

MIN

Frequency or Amount of EffortMIN MAX

Watchchild

Prevent discharge>120 F

Adjust valve on heater

Should there be a committee that screens the safety ofbaby/toddler products before they go on the market?

Will this encouragethe caretaker toleave for a moment?

Messages such as this are too often unseen or ignored.

Whose Decisions Determine Injury?

• Designers

• Administrators

• Legislators

• Regulators

• Architects

• City planners

Therefore we need to educate the decision-makers.

Drownings in Australia, Ages 1-4Two cities with similar ratios

of pools but different fencing regs.

Pools

/100 homes

Drownings

/100,000

children

Canberra

(no fencing)

9 2.7

Brisbane

(fencing mandated)

8 0.3

Airbag regulations followed years of work by scientists and advocates. (Initial deaths of unrestrained children resulted in design changes.)

Findings re Compact Pickup Trucks

Children in 2nd row of compact pickups:• Higher risk of injury than front row occupants

– Predominantly head injuries

• Higher injury risk than children in 2nd row of other vehicles– Higher risk of contact– Higher risk of injury given contact

• Design of vehicles is decided by manufacturers who can be influenced by data.

Injuries to Child Passengers by Vehicle TypeFrequency of AIS 2+ head injuries

Winston et al. JAMA 287,1147-1152, 2002

4.3%

0.7% 1.2% 0.5% 0.6%

0%

1%

2%

3%

4%

Significant Injury

Compact PU Fullsize PU Car Pass. Van SUV

PU=pickup

Look closely; do you think warnings work??

Photo by AL Dannenberg

Contributors

• Andrew L. Dannenberg, MD– U.S. Centers for Disease Control

• Alfred J. Saah, MD– Merck Research Labs

• Stephen P. Teret, JD– Johns Hopkins School of Public Health