The latest CDC "Dog Bite: Fact Sheet" includes a disclaimer regarding this study, saying that
"it does not identify specific breeds that are most likely to bite or kill, and thus is not appropriate for policy-making decisions related to the topic. Each year, 4.7 million Americans are bitten by dogs. These bites result in approximately 16 fatalities; about 0.0002 percent of the total number of people bitten. These relatively few fatalities offer the only available information about breeds involved in dog bites. There is currently no accurate way to identify the number of dogs of a particular breed, and consequently no measure to determine which breeds are more likely to bite or kill."