produksjonsprosessen: quality in the swedish crime registry
TRANSCRIPT
Anton Färnström
The Swedish National Council for Crime Prevention (Brå)
2013-08-15
How the architecture of a coding system will
affect statistical quality
The criminal statistics in Sweden
Police Courts
Crime prevention council (Brå)
Prosecution statistics
• Prosecutions
• Prosecutions regarding
narcotics
Crime statistics
• Reported offences
• Cleared up crimes
• Suspected persons
Attorney's office
Recidivism in
crime
Quality of official statistics
“The quality of the raw data is the key for a reliable
production of statistics”
The government’s survey support
The crime codes
Four digit codes
Encapsulate legal information
Encapsulate context information
The crime codes - examples
9816 – Theft of boat motor
0375 – Assault, aggravated, against women 18 years or older, unfamiliar with offender, outdoors
0385 – Assault, aggravated, against women 18 years or older, unfamiliar with offender, indoors
1610 – Other crimes against chapter 16
Study design
• 1600 police reports covering 8 categories
• Recoding done by two lawyers
• Extent and effect of coding errors estimated
Results quality study – fraud
-10 000
-8 000
-6 000
-4 000
-2 000
0
2 000
4 000
6 000
8 000
10 000
12 000
14 000
Other
fraud
With
credit
card
With false
invoice All
others Via
internet Computer
fraud
+ 35 %
+ 35 %
- 15 % - 19 % - 13 % - 6%
Results quality study – assault
In close relationship
Not in close relationship
Official statistics Estimated true proportions
Results quality study – all categories
Summary of results
• Good quality at higher hierarchical levels
• Lower quality of context information
• Similar quality problems as in 1978
Lessons for the future
• Quality correlates with administrative needs
• Detailed instructions are no general solution
to coding errors
• Close contact with personnel doing the
registration is needed
• Coding quality needs to be taken into account
when creating statistical products
