<P> Research based on the NCVS data set largely confirms Hemenway's earlier results, showing approximately 55,000 uses of a firearm in self - defense from a violent crime in the United States for the 3 - year period of 2013 - 2015 . </P> <P> In a review of his own research, Kleck determined that, of 41 studies half of them found a connection between gun ownership and homicide but these were usually least rigorous studies . Only six studies controlled at least six statistically significant confound variables, and none of them showed a significant positive effect . Eleven macro-level studies showed that crime rates increase gun levels (not vice versa). The reason that there is no opposite effect may be that most owners are noncriminals and that they may use guns to prevent violence . </P> <P> Commenting on the external validity of Kleck's report, David Hemenway, director of the Harvard Injury Control Research Center, said: "Given the number of victims allegedly being saved with guns, it would seem natural to conclude that owning a gun substantially reduces your chances of being murdered . Yet a careful case - control study of homicide in the home found that a gun in the home was associated with an increased rather than a reduced risk of homicide . Virtually all of this risk involved homicide by a family member or intimate acquaintance ." Kleck however pointed out that most of the firearms used in the Kellermann study were not the same ones kept in the household by the victim . Similarly in 2007 when the Permit - To - Purchase law was repealed in Missouri, 2008 saw a 34% increase in the rate of firearm homicides in that year alone, and the figure continues to be higher than the figure pre-2007 . </P> <P> One study found that homicide rates as a whole, especially those as a result of firearms use, are not always significantly lower in many other developed countries . Kleck wrote, "...cross-national comparisons do not provide a sound basis for assessing the impact of gun ownership levels on crime rates ." One study published in the International Journal of Epidemiology, which found that for the year of 1998: "During the one - year study period (1998), 88,649 firearm deaths were reported . Overall firearm mortality rates are five to six times higher in high - income (HI) and upper middle - income (UMI) countries in the Americas (12.72) than in Europe (2.17) or Oceania (2.57) and 95 times higher than in Asia (0.13). The rate of firearm deaths in the United States (14.24 per 100,000) exceeds that of its economic counterparts (1.76) eightfold and that of UMI countries (9.69) by a factor of 1.5 . Suicide and homicide contribute equally to total firearm deaths in the U.S., but most firearm deaths are suicides (71%) in HI countries and homicides (72%) in UMI countries ." </P>

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