Breed Risk RAtes

Our breed risk rates measure fatal dog attacks (scientifically known as dog bite-related fatalities or DBRFs) relative to breed population sizes. The DBRF statistics used to calculate the risk rates are sourced from a peer-reviewed study conducted by the U.S. Centers for Disease Control (CDC) and published by the American Veterinary Medical Association (AVMA). The study analyzed 20 years of dog bite incident data and identified over 25+ breeds associated with DBRFs. Risk rates are a scientifically accepted method for assessing risk compared to other statistics that simply count incidents. The data, sources, and calculations for the breed risk rates are all provided below.

Breed Risk Rates

Calculating Breed Specific Risk:
​In order to assess any breed specific risk, risk must be measured using dog bite incidents relative to a breed's population size to calculate a risk rate. Calculating a risk rate is a universal standard and a scientifically accepted method for assessing risk. For example:
  • Breed-A is responsible for 5 incidents and has a population size of 1,000. Its risk rate is .005 (5÷1,000).
  • Breed-B is responsible for 100 incidents and has a population size of 100,000. Its risk rate is .001 (100÷100,000).
  • Even though Breed-B is responsible for 20x more incidents, Breed-A is actually associated with 5x more risk than Breed-B.

​Benefits of Risk Rates:
  • Risk rates are a universal best-practice and a scientifically accepted method for assessing risk.
  • Breed risk rates rarely change - breeds will not suddenly become more or less "dangerous", only their populations change.
  • Risk rates are resilient to changes in populations - if a population grows, the risk rate will remain the same. For example, if the population of Toyota Camrys doubled, the number of accidents that involve Camrys would also double - not because the car has become "more dangerous", but simply because its population has increased (the Camry's risk rate would remain the same). The same is true for dogs, if a breed becomes more popular then its bite-related incidents will also increase - not because the breed has become "more dangerous", but simply because its population has grown. This is an important fact because as breed populations change over time due to their popularity (and therefore also the number of incidents associated with each breed), their risk rates will remain the same.

Breed Risk Table

The breed risk table uses dog bite-related fatality (DBRF) statistics sourced from a peer-reviewed study conducted by the U.S. Centers for Disease Control (CDC) that analyzed 20 years of dog bite incident data. As noted above, one of the benefits of risk rates is that they are resilient to breed population changes over time, so the DBRF dataset from this previously completed CDC study is still fully valid today. The table is sorted by descending risk rates, a higher risk rate indicates a potentially higher risk breed based on the breed's DBRF count relative to its population size. The DBRF risk rates (last column) have been normalized to show the number of DBRFs per 100,000 dogs for each breed or dog type. All relevant data, sources, and calculations are provided below.
Notes:
  • The breed risk table includes breeds listed in the CDC report's results table for breeds associated with 3 or more DBRFs. Other breeds associated with DBRFs listed in the CDC report but not included in the table (because their risk rates are lower than .40 and/or because their populations are unknown) include: Labrador Retriever, Boxer, Collie, Bullmastiff, Sled-Type, Wolf-Dog Hybrid, mixed breed, and others.
  • Due to the many complexities and factors inherent to: (1) accurate breed identification; (2) assessing all factors that contribute to DBRFs; and (3) estimating breed population sizes; we firmly believe that a breed's risk rate would need to be well over 10 in order to infer a higher level of risk specific to any dog breed(s) or dog type(s).
  • If the DBRFs associated with pitbull-type dogs were multiplied by 3x (from 76 to 228), their risk rate would increase from 0.97 to 2.92 - which would be higher, but still statistically in-line with the risk rates of other breeds.

Sources & Data

Sources & Calculations:
  • Dog Bite-Related Fatalities (DBRFs): Sourced from CDC Study ​(DBRFs over a 20-year period, Table 2 - Death-based approach totals)
  • Population %: Sourced from AKC Breed Registration Statistics (using breed population data from the 1997 report to ensure that population data is consistent with the CDC study ending in 1998)
  • Population Total: [Population % x 65,000,000] (estimated dog population in the U.S. in 1998, the last year of the CDC study)​
  • DBRF Risk Rate: [(DBRFs ÷ Population Total) x 100,000] (provides number of DBRFs per 100,000 dogs)
  • ​​*Pitbull-Type Populations: For the purpose of objectivity and removing any bias related to population estimates, two population estimates are included in the Breed Risk table for pitbull-type dogs:
    • ​12%: The estimate for the total pitbull-type dog population in 1998, the last year of the CDC study. Today, we estimate the total pitbull-type dog population to be 20%. However, in order to account for substantial increases in the popularity of pitbull-type dogs over the last 10-20 years, we estimate that their population was 40% lower (at 12%) in 1998.
    • 6%: The alternative estimate for the pitbull-type dog population (frequently claimed by groups promoting Breed Specific Legislation); however, even at a population of 6% the risk rate of pitbull-type dogs is still fully in-line with other breeds.
​
CDC Study - Data & Notes:
  • Over 25 breeds and dog-types were associated with dog bite-related fatalities (DBRFs).
  • The majority (72%) of DBRFs were attributed to non-pitbull type breeds.
  • 28% of DBRFs were attributed to all 4 "pitbull-type" breeds (and their mixes) combined - or an estimated 7% for each of the 4 individual "pitbull-type" breeds.
  • ​The study rejects breed-specific legislation (BSL) assessing it as problematic and ineffective.
All dogs can be great dogs, regardless of breed ... State Farm determines risk based on a dog's bite history rather than breed.
- State Farm Insurance