Firearm Injury Interventions

Ownership and Licensing/Safe Storage

Background

In this section, we review the impact of legislation designed to decrease access to guns, especially handguns. Legislation may intend to decrease access to all segments of the population for certain types of guns, or to decrease access to certain segments of the population, such as children through safe storage laws.

Evaluation of these laws is difficult, since there are no randomized controlled trials of such legislation. Some of the studies are ecological studies, in which entire communities are compared. These studies are potentially flawed by the fact that other differences, in addition to gun legislation, certainly exist between such communities, and many other factors can affect firearm death rates. In addition, one is attempting to analyze effects on individuals by looking at entire populations.

Other evaluations have relied on sophisticated and complicated statistical techniques to determine changes in rates of events over time. There are also other factors which change over time, which most of these analyses do not take into consideration. The interpretation of these results is also not intuitive for many.


Review of legislation to restrict firearm ownership and access:

Author

Kleck et al., 1993

Study design and target population

City level cross-sectional study of 170 US cities over 100,000 population in 1980.

Intervention

19 major categories of firearms restriction at both state and city-level.

Outcomes

Total rates and gun specific rates per 100,000 for homicide, suicide, aggravated assault and robbery in 1979-81, and gun prevalence rates.

Results

(1) Gun control restrictions have no net effect on gun prevalence levels

(2) Gun control restrictions generally have no net effect on violence rates.

102 assessments of effects of different gun laws on different types of violence, 7 indicated good support, 11 partial support for hypothesis of gun control efficacy.

Study quality and conclusions

Major assumption that higher violent crime rates could increase gun prevalence and higher gun prevalence would increase violence rates.

Limitations: no information available on how strictly gun permit and licensing laws administered.

Supportive findings: Mandatory penalty laws reduce robbery; local dealer licensing requirements reduced aggravated assault, robbery and suicide; gun owner licensing or purchase permits; bans on possession of guns by criminals and mentally ill, stronger controls on illegal carrying.



Author

Loftin et al., 1991

Study design and target population

Before/After study design. Entire population of Washington, DC, 1968-1987. Comparison population, adjacent metropolitan areas in Virginia and Maryland.

Intervention

Firearms Control Regulations Act effective February, 1977 required registration of handguns and long guns as well as safe storage

Outcomes

Firearm and non-firearm rates of suicide and homicide.

Results

Reduction in firearm homicides (3.3 per month, 25%, p=0.001) and suicide (0.6 per month, 23%, p=0.005) with no reduction of non-firearm homicide and suicide. No significant change in non-firearm homicide or suicide.

Study quality and conclusions

Restrictive handgun licensing was associated with significant decline in firearm homicides and suicides. No decline in these rates in adjacent areas of Maryland and Virginia which had no registration requirements. The authors were unable to measure non-fatal firearm injuries.


Author

Mundt, 1990, with comments by Hung, 1993 and  Lester et al., 1994

Study design and target population

Ecological study design comparing Canada to the United States. Evaluated the period 1974-1987.

Intervention

1977 Criminal Law Amendment Act in Canada which required a firearms acquisition certificate for purchase, increased registration requirements, prohibited automatic weapons, sawed -off shot guns and rifles and increased penalties for firearm related crime. Major provisions effective in 1979.

Outcomes

Rates per 100,000 for violent crime, suicide, accidental death divided in to gun and non-gun categories. Major outcomes compared Canadian rates to U.S. rates

Results

All data are presented as yearly rates for each outcome in Canada and U.S. Found a greater decrease in firearm robbery rates in Canada; accidental gun deaths decreased in both countries. No change in homicide and suicide rates.

Study quality and conclusions

The author concludes that there was no impact of legislation on the rate of violent crime or gun-related violent crime in Canada. Study uses total U.S. rates to adjust for secular trends in various outcomes.

Study design is very weak and doesn’t adequately adjust for differences between the two countries (proportion of gun ownership, changes in gun laws, large differences in crime rates). Evaluating the entire country could mask regional changes.

Critique by Hung (ref) reports steeper decreases in firearm crimes and deaths in Canada indicate law successful.

Critique by Lester used linear regression to evaluate suicide rates from 1978-85 and reports decrease in firearm suicides (p=.04) and decrease in proportion of suicides due to firearms (p=.03).

More rigorous time series analysis adjusting for confounding variables is necessary to determine law’s effects.



Author

Sloan et al., 1990

Study design and target population

Ecological study comparing firearm suicide rates in King County, WA and Vancouver Metropolitan Area, B.C. 1985-1987

Intervention

Strict regulations govern the purchase, ownership, and carrying of firearms in Vancouver. Concealed weapons are not permitted in Vancouver, a restricted weapons permit is required for handgun purchase, and self defense is not a valid reason for handgun purchase.

King County allows legal purchase of handguns for self-defense and concealed weapon permits are easily obtainable.

Handgun ownership in Canada was about 1/4 that of US.

Outcomes

Rates of suicide from all causes and from firearms

Results

Risk of suicide did not differ in King County compared to Vancouver (RR=0.97, 0.87-1.09). The rate of suicide by firearms was higher in King County (RR= 2.34, 1.90-2.88) related to a 5.7 fold increased rate of suicide by handguns (RR=5.7, 4.08-7.93). The difference in the rate of suicide by firearms was offset by a 1.5 fold higher rate of suicide by other means in the Vancouver area. Young adults 15-24 years had a higher rate of suicide in King County (RR=1.38, 1.02-1.96) due to a RR= 9.56 (3.62-25.25) risk of suicide by handguns.

Study quality and conclusions

Restricting access to handguns may be associated with a decreased rate of suicide for certain segments of the population.

The two cities were similar in size, geography, unemployment rates, education and income.

It was not possible to adjust for some important confounders such as illegal drug-related activity, illicit gun sales, and SES of the victims.

The study also has the limitations of all ecological studies.



Author

Sloan et al., 1988

Study design and target population

Ecological study comparing firearm homicide rates in Seattle, WA and Vancouver, B.C. 1980-1986

Intervention

Strict regulations govern the purchase, ownership, and carrying of firearms in Vancouver. Concealed weapons are not permitted in Vancouver, a restricted weapons permit is required for handgun purchase, and self defense is not a valid reason for handgun purchase.

Seattle allows legal purchase of handguns for self-defense and concealed weapon permits are easily obtainable.

Handgun ownership in Canada was about 1/4 that of US.

Outcomes

Rates of homicide (all causes), firearm homicide, simple assault, robbery, burglary

Results

Relative risk of homicide, adjusted for age and sex, was significantly higher in Seattle (RR=1.63, 1.28-2.08). Firearm homicide rate was 5 fold higher in Seattle. (RR=5.08, 3.54-7.27).

Firearm assault rate was 7 times higher in Seattle (RR=7.7, 6.7-8.7) while the simple & aggravated assault rates, respectively, were only slightly higher in Seattle (RR=1.18, 1.15-1.20) and (RR=1.16, 1.12-1.19).

Robbery , burglary and non-gun homicide rates were equal.

Study quality and conclusions

Restricting access to handguns may reduce homicide rate in a community. The two cities were similar in size, geography, unemployment rates, education and income.

It was not possible to adjust for some important confounders such as illegal drug-related activity, illicit gun sales, and SES of the victims.

The study also has the limitations of all ecological studies.



Author

Jung et al., 1988

Study design and target population

Before/After study design to evaluate gun control legislation in East St. Louis, IL (1981) and Evanston, IL(1982) Control city Rock Island, IL.

Intervention

Law increased penalties for carrying firearms on street (East St. Louis); ban on possession of all handguns in Evanston.

Outcomes

Firearm assaults and firearm robberies. Data source Uniform Crime Report (UCR) Used time series analysis adjusting for seasonality.

Results

Temporary reduction in firearm assaults in E. St. Louis and Evanston BEFORE the law took effect (p=0.05) followed by significant increase after the later went into effect in E. St Louis and no change in Evanston .

Firearm robberies showed the same pattern in E. St. Louis but no change in Evanston.

Study quality and conclusions

No lasting effect of legislation. Pre-intervention decrease in Evanston and E. St. Louis possibly due to extensive media campaign. Control city, Rock Island IL showed no change during either period. There was no increase in assaults using knives or other weapons in any of the 3 cities.


Author

Lester et al., 1986

Study design and target population

Cross-sectional study involving entire population of the United States in 1960 and 1970

Intervention

Handgun control statutes rated on a Guttman scale of strictness

Outcomes

Death rates for homicides, suicides and accidents. Source: Vital Health and Statistics

Results

States with stricter handgun control statutes had lower firearm suicide rates and lower overall suicide rates. No relation between strictness of laws and homicide rates.

Study quality and conclusions

Study poorly designed and analyzed. Authors conclusions can not be based on the data presented. Correlation coefficients are not the appropriate statistical measure. Regression coefficients would illustrate the quantitative relationship. Other problems-no adjustment for any type of confounding or secular trends; variations and changes in laws. Not known when laws enacted.


Author

Lester et al., 1982

Study design and target population

Ecological study involving entire population of the United States

Intervention

Handgun control laws in 1968; rated on 8 characteristics and ranked on Guttman scale of strictness (from 1-7) Factor analysis used to define 3 principal components of gun laws: restrictions on seller, restrictions on buyer and restrictions on carrying guns.

Outcomes

Homicide and suicide rates by various methods including firearms. Data from Vital Statistics of the United States (1960-1970)

Results

Lower firearm suicide rates in states with stricter handgun laws (in 1960 r= -0.46 and r= -0.52 in 1970) but an increase in suicide rate by other means r=0.34 and r=0.43 for 1960 and 1970. No statistically significant change in firearm homicide.

Study quality and conclusions

Strict handgun control laws appeared to reduce firearm suicide rates, but had no effect on firearm homicide rates.

No adjustment for age of SES of population; no information available on enforcement or number of guns available prior to legislation.

Summary of firearm ownership and licensing/safe storage

The evaluation of the impact of these laws is based on ecological analyses or time series analyses. As is the case with mandatory sentencing legislation evaluations, there are methodological problems inherent in these types of analyses. The conclusions which can be made form the available are unclear, since the results of the studies are contradictory.

Recommendations on ownership and licensing/safe storage

Recommendations on future research