The challenge
Residential fire injuries were concentrated in one low-income part of the city.
The case
Using injury surveillance data, the Oklahoma State Department of Health found that a 24-square-mile area of Oklahoma City had the city's highest rate of residential fire injuries. In 1990 workers went door to door handing out about 10,100 smoke alarms to 9,291 homes. Over the following four years, the annual fire injury rate in the target area fell 80%, from 15.3 to 3.1 per 100,000 people, while in the rest of the city it rose slightly, from 3.6 to 3.9. Injuries per 100 fires fell 74% in the target area while rising slightly in the rest of the city. Four years later, 45% of the alarms were still working.
Why it worked
Data were used to send alarms to where injuries actually happened, and alarms went directly into homes. The study was not randomised, and later trials elsewhere did not repeat the effect, so results depend on getting alarms installed and working.
Sources
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