Transcript Injury Surveillance Thomas Songer, PhD University of Pittsburgh

Injury Surveillance
Thomas Songer, PhD
University of Pittsburgh
Why should we
be concerned
with monitoring
injuries?
Definitions
Prevention
• Reducing the incidence of disease
• Reducing the prevalence of disease
Control
• Ongoing programs aimed at reducing
the incidence or prevalence of disease
Last, Dictionary of Epidemiology
Public Health Approach to
Injury Control and Prevention
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Define the Magnitude of the Problem
Identify associated causes and risk factors
Design and Implement the Intervention
Evaluate the Intervention
Epidemiology is a Science of Rates
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death rates
disability rates
hospitalization rates
incidence rates
prevalence rates
numerator
denominator
Injury Deaths, Australia, 1992
Male
Female
number of deaths
700
600
500
400
300
200
100
0
10-14 yrs
30-34
50-54
70-74
Age Group
Harrison, 1995
Injury Death Rates, Australia, 1992
deaths per 100,000 pop.
Male
Female
200
150
100
50
0
10-14 yrs
30-34
50-54
70-74
Age Group
Harrison, 1995
How do we
identify injuries?
Approaches Towards Monitoring
Injury in the Population
Death Certificates
Population Surveys
Surveillance
Registries
Capture-Recapture
Government Surveys
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National Health Interview Survey
National Hospital Ambulatory Care Survey
National Hospital Discharge Survey
Behavioural Risk Factor Survey and
Surveillance
Provide a better picture of the health
status of the population
Surveillance:
Systematic, regular ascertainment
of incidence using methods
distinguished by their practicality,
uniformity, and frequently their
rapidity, rather than by complete
accuracy.
Last, 1990
Types of Surveillance
•Active
•Passive
Active Surveillance
• the collection of data on a
disease by regular outreach.
Designated medical personnel
are called at regular intervals
to collect information on the
new cases of disease.
monitoring domestic violence in
emergency departments
Passive Surveillance
• data generated without contact
by the agency carrying out the
surveillance. Reportable
diseases fall under this type of
surveillance.
spinal cord injuries
Sentinel Events
• An event(s) that can be
used to assess the
stability or change in the
health of a population.
John Last
Dictionary of Epidemiology
Registry:
A file of data concerning all cases
of a particular disease or other
health-relevant condition in a
defined population such that the
cases can be related to a
population base.
Last, Dictionary of Epidemiology
Where do the data for
the numerator and
denominator come from
in injury surveillance?
Police
Self-Treat
doctor
EMS
Emergency Dept.
Injury
Hospital
Morgue
Trauma Center
Rehab Center
Robertson, 1992
The monitoring of incidence unfortunately
is more complicated than the monitoring
of mortality, because incidence data are
hard to come by, registration of cases is
even now seldom complete, and increases
in the recorded rates may be due to an
increase in the efficiency of registration.
Sir Richard Doll, 1990
Numerator Issues
?
• Definition
• Ascertainment
• Severity
ICD-9 Codes
N Codes - Nature of injury, anatomy
E-Codes - External cause of injury
E-codes
Are often missing on medical records
Some states now require their use in ED
and Hospital Admission records
Important for identifying cause of injury
and designing control programs
Help to assign intent
Sources for Monitoring Injuries
Woodland Hills School District
4 month
recall
medical
excuses
1 month
student recall
attendance
records
Percent ascertainment for each of
the four monitoring sources
90
80
70
60
50
40
30
20
10
0
1 month
medical
attendance 4 month
Data Sources and Injury Severity
No injury
Mild
Moderate Severe
Fatal
Survey
Doctor visit
Hospital adm.
Trauma ctr.
Death cert.
Rogams, 1995
Denominator Issues
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• Population Base
• Which Denominator?
What is the crash risk related
to older drivers? How
important is this risk?
Crash Involvement Rate
per 1000 licensed drivers
200
150
100
50
0
16 20 25 30 35 40 45 50 55 60 65 70 75 80 85+
Age
NHTSA, FHWA
per 100 million miles VMT
Involvement Rate by Mileage
2000
1500
1000
500
0
16 20 25 30 35 40 45 50 55 60 65 70 75 80 85+
Age
NHTSA, FHWA
Fatality Rate
per 100 million miles
12
10
8
6
4
2
0
16 20 25 30 35 40 45 50 55 60 65 70 75 80 85+
Age
NHTSA, FHWA
Limitations in Injury Surveillance
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Few standards or guidelines
Lack of population-based data
Inflexibility of data systems
Inability to integrate data systems
Important data elements are not
collected
A Minimum Basic Dataset for
Unintentional Injuries
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Age, Gender, Ethnic Group
Place of occurrence
Date of Injury
Outcome of Injury
Location of Injury
Activity when accident happened