Introduction to Violence
Epidemiology
With a focus on crime-related violence
Thomas Songer, PhD
University of Pittsburgh
tjs@pitt.edu
What is Violence?
What actions characterize violence?
Definition of Violence
…...To understand violence, you
need to define violence
How would you define violence?
Definition of Violence
• wide ranging in the literature
– crime-related, spouse, child, firearms
• National Research Council
– behaviour by individuals that
intentionally threaten, attempt, or
inflict physical harm on others
www.nap.edu
Categories of Violence
• Crime-based Violence
– Homicide
– Robbery
– Rape
– Serious Assaults
• Firearm-related Violence
• Suicide
• Domestic Violence
Categories of Violence
• Crime-based Violence
• Firearm-related Violence
• Suicide
– successful and unsuccessful
• Domestic Violence
– partner
– child
– elder
Public Health Approach to Disease
Control
Monitoring of
incidence
prevalence
Identify
risk factors
Identify
morbidity
mortality
cost
social
genetic
environmental
Intervene
Prevention
Evaluate
Monitoring
Identify
risk factors
Intervene
Surveillance
Evaluate
Surveillance of Violence from
Crime
• Death Certificates
• Police Reports
– Uniform Crime Reports
• Government Surveys
– National Criminal Victimization Survey
• Medical Databases
Leading Causes of Death, U.S.
1995
SOURCE: NCIPC, 1998.
1995
1990
1985
1980
1975
1970
1965
1960
1955
1950
1945
1940
1935
1930
1925
1920
1915
1910
Rate per 100,000 pop.
Trends in Homicide, United States, 1910-96
12
10
8
6
4
2
0
Year
NCHS
Homicide Rates; Selected Countries
Norway
France
Holland
England
Denmark
Canada
Australia
New Zealand
Israel
Scotland
United States
0
2
4
6
8
10
Rate per 100,000 population
ICE, 1998
Crime Violence Data Sources
• Federal Bureau of Investigation
– Uniform Crime Reporting System
– NIBRS
• National Institute of Justice
– National Crime Victimization Survey
Trends in Violent Crime, Pennsylvania
1998
1997
1996
1995
1994
1993
1992
1991
1990
45,000
47,000
49,000
51,000
53,000
Number of Violent Crimes
1994 UCR
Down with Crime
“How to Cut City’s Crime Rate:
Don’t Report It”
“Philadelphia’s Crime Data
Discarded by FBI”
Philadelphia Inquirer 1997-98
The Pyramid of Violent Crime in the U.S., 1994
1.8% admitted to hospital
3.4% seen in an emergency department
14.5% received medical care
25% resulted in physical injury
41% reported to police
10,860,000 violent crimes
1994 NCVS
National Estimates of Rape and
Sexual Assault
• Uniform Crime Reports
(1994)
• 102,216
• National Crime
Victimization Survey
(1994)
• 168,000 rapes
• 149,000 attempted
• 117,000 sex. assault
• National Violence
Against Women Survey
(1995-96)
• 302,100 females affected
• 876,000 rape events
Injuries from Crime
Medical Sources and Police Sources
“You look at them as victims, we look
at them as suspects”
Definition of Health Care Events
Related to Violence
• Based on E-codes
– E960-969 Homicide and injury
purposely inflicted
– E coding to distinguish crimes is
relatively poor
The Pyramid of Rape in the United States, 1994
3.4% admitted to hospital
4.6% seen in an emergency department
17.6% received medical care
32% reported to police
433,000 rapes/sexual assaults
1994 NCVS
Problems in Crime Violence
Surveillance
• Definition of violence may not be
standard across sources
• Reporting of violence by victims varies
considerably
• Rape
• Reporting of violence by the police may
vary
Monitoring
Identify
risk factors
Intervene
Evaluate
Risk Factor Identification
Epidemiologic Model
Host
Agent
Environment
Crime
Victim
Perpetrator
Environment
Violent Crime Victims by Age Group,
Pennsylvania, 1994
Percent
35
30
25
20
15
10
5
0
< 11
11-14
15-24
25-34
35-44
45-54
55-64
65+
1994 UCR
Death Rates from Homicide, 1980-86
per 100,000 pop.
Native American
White
African American
Asian
70
60
50
40
30
20
10
0
0
8
10
20
30
40
50
60
70
80
Rape Victims by Age Group, Pennsylvania, 1994
Percent
30
25
20
15
10
5
0
65+
5
60-6
9
55-5
4
50-5
9
45-4
4
40-4
9
35-3
4
30-3
9
25-2
4
20-2
9
15-1
yrs
4
11-1
<11
1994 UCR
Percent Victimized
Criminal Victimization in Schools by
Student Age, US, 1995
8
7
6
5
4
3
2
1
0
12
13
14
15
16
Age (years)
17
18
19
Homicide by Type of Weapon, Pennsylvania, 1994
Firearm
Knife
Personal
Weapon
Other Weapon
0
10
20
30
40
50
60
70
Percent Distribution
1994 UCR
Location of Robberies in the United
States, 1997
Street or Highway
50
Commercial Business
13.8
Gas Station
2.4
Convenience Store
5.7
Residence
11.6
Bank
1.9
Other
14.6
0
10
20
30
40
50
60
Percent
1997 UCR
Homicide Rate per 100,000 worker-years
Workplace Homicide Rates by Occupation
45
40
35
42.3
30
25
20
15
9.1
10
5
0
9.1
9
8.9
0.83
Taxicab
Drivers
Private
Security
Guards
Law
Enforcement
Officers
Retail
Cashiers
Retail
Supervisors
and
Propietors
All
Occupations
North Carolina, 1977-1991, n= 361
Perpetrators
Percent
Prevalence of Serious Violence
by Age Pittsburgh
18
16
14
12
10
8
6
4
2
0
10
11
12
13
14
15
Age
16
17
18
19
Prevalence of Serious Violence in
Pittsburgh by Ethnicity and Age
African American
Caucasian
25
Percent
20
15
10
5
0
10
11
12
13
14
15
Age
16
17
18
19
Cumulative Prevalence of Serious
Violence by Age 16
45
40
35
Percent
30
25
20
15
10
5
0
Rochester
Females
Denver
Females
Rochester
Males
Pittsburgh
Males
Denver
Males
Monitoring
Identify
risk factors
Intervene
Prevention
Evaluate
Prevention Strategies
• Criminal Justice
• Behavioural
• Environmental
• Public Health
Haddon Matrix
Adapted from Haddon, 1980.
Violence in Pennsylvania
http://www.pitt.edu/~tjs/vio/viopenn.htm