According to recent estimates, approximately 72 million dogs live in the United States, with 37% of all US households, or approximately 43 million homes, owning at least 1 dog.1 Exposure to dogs, therefore, is almost ubiquitous in today's society. Not surprisingly, dog bites are relatively common in the United States, with 157 of 9,672 adults participating in a national, random-digit-dial survey reporting having been bitten by a dog.2 Dog bite-related fatalities, however, appear to be extremely rare, occurring at a rate of approximately 27/y from 1999 through 2006 in a human population of just below 300 million,a or approximately 3 fatal bites/10 million dogs/y. Although there is widespread agreement that every effort should be made to reduce the incidence of dog bite-related injuries, how to best accomplish this is a subject of considerable debate.
One commonly suggested method for reducing the incidence of dog bite-related injuries is BSL, which bans, restricts, or imposes conditions on ownership of specific breeds of dogs presumed to pose greater risk of biting people.3 The AVMA, American Kennel Club, and major animal protection and animal control groups in the United States have all strongly discouraged the use of BSL as a means of reducing the incidence of dog bite-related injuries,4–7 contending that it is an ineffective method of dealing with this problem. Nevertheless, BSL continues to be a popular response to perceived concerns about dangerous dogs, particularly following a serious dog bite-related injury or fatality in a community.
In the present manuscript, we discuss factors influencing public perception of the risks associated with dog bites, particularly with respect to particular dog breeds, and examine how these factors result in promotion of BSL. In addition, we describe a novel method of demonstrating the implausibility of improving public safety via BSL through calculation of a risk-based statistic, the NNB, which is similar to the NNT statistic used in evidence-based medicine.8,9
Number needed to ban
Number needed to treat
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