25. The U.S. gun stock
We analyzed a national representative household telephone survey of over 2750 adults conducted in 2004.
Major findings: 38% of households (45% of men and 11% of women) reported owning at least one firearm.  Almost half (48%) of gun owners report owning four or more guns with a few possessing large numbers of guns; 64% of gun owners own at least one handgun.  Gun ownership remains widespread, but a smaller percentage of gun owners possess an increasing percentage of the gun stock.
Publication: Hepburn, Lisa; Miller, Matthew; Azrael, Deborah; Hemenway, David. "The US Gun Stock: Results from the 2004 National Firearms Survey."  Injury Prevention. 2007 13:15-19.

26-27. Differences among gun owners
We analyzed data from national random-digit-dial telephone surveys.
Major findings: National Rifle Association (NRA) members are similar to other gun owners in many respects, but they are more likely to own six or more guns. Unlike the NRA leadership, both NRA members and non-member gun owners support waiting periods and mandatory registration of handguns.
Owners of semi-automatic weapons are more likely than other gun owners to be male, own a gun for protection, and report binge drinking.
Publication: Weil, Douglas S; Hemenway, David. "I am the NRA: An Analysis of a National Random Sample of Gun Owners." Violence and Victims. 1993; 8:353-65. See also Weil, Douglas S; Hemenway, David. "A Response to Kleck". Violence and Victims. 1993; 8:377-85.
Publication: Hemenway, David; Richardson, Elizabeth. "Characteristics of Automatic or Semi-automatic Firearm Ownership." American Journal of Public Health. 1997; 87:286-88.

28-29. Guns on college campuses
Using data from mailed surveys of 10,000-15,000 undergraduates in 1997 and 2001, we examined the prevalence of surveys. We provided the first information on the number of students who bring guns to college, and the risk factors for college gun possession.
Major Findings: In 1997, approximately 3.5% of undergraduates reported having a working firearm at college. Students with guns were more likely to be male, white, live in a fraternity, live off campus, binge drink, drive after drinking, and be injured severely enough to require medical attention. Students with guns at college are more likely to engage in alcohol-related behaviors that put themselves and others at risk of injury.
The 2001 survey confirmed these findings, and also showed that guns on college campuses were more common in regions with higher levels of gun prevalence, and that gun threats to college students were also more common in these regions.
Publications: Miller, Matthew; Hemenway, David; Wechsler, Henry. "Armed and Dangerous? Guns at College." Journal of American College Health. 1999; 48:7-12.
Publication: Miller, Matthew; Hemenway, David; Wechsler, Henry.  "Guns and Gun Threats at College."  Journal of American College Health. 2002; 51:57-65.

30. Batterers gun possession.
We analyzed survey data of over 4,500 men in Massachusetts batterers intervention programs.
Major findings: Risk factors for having a gun included having gambling problems, having attempted murder, and having threatened a partner with a firearm.
Publication:  Rothman, Emily F.; Johnson, Renee M.; Hemenway, David.  "Gun Possession among a Sample of Massachusetts Batterer Program Enrollees."  Evaluation Review. 2006; 30:283-95. 

31. Gun owners and mental illness
We added questions to, and analyzed data from the National Comorbidity Study.
Major findings:  Gun owning households do not have more mental health problems than non-gun owning households; differences in mental health do not explain why gun owners and their families are at higher risk for completed suicide than non-gun owning families.
Publication: Miller, Matthew; Molnar, Beth; Barber, Catherine; Hemenway, David; Azrael, Deborah. "Recent Psychopathology, Suicidal Thoughts and Suicide Attempts in Households with vs. without Firearms: Findings from the National Comorbidity Study Replication."  Injury Prevention. 2009; 15:183-87.