Keith Vodden Dr. Douglas Smith - Transports Canada

Appendix A—Detail on Calculations of the Ontario Model
Exhibit A-6
Revisions for 2004 Reflecting the Transfer of PDO Collisions
involving Allocated Injuries to Injury Collisions
Characteristic of average
injury collision
Number of
injuries to
transfer
from PDO
collisions
Like PDO
collisions
needed to
transfer
injuries
Transfer if
based on
maximum
collisions
needed
Actual
transfer
from PDO
to injury
collisions
(#) (#) (#) (#)
Collisions 1.00 11878
Injuries:
Major 0.09 637 7,361 1,028 637
Minor 0.96 11,366 11,878 11,366 11,366
Minimal 1.02 7,119 7,007 12,068 7,119
Vehicles damaged:
Demolished 0.21 2,527
Severe 0.45 5,304
Moderate 0.52 6,233
Light 0.52 6,179
None 0.18 2,163
Given the characteristics of an average collision involving injury 7,361; 11,878;
or 7,007 collisions would need to be transferred depending on whether the transfer
decision was based on the 637; 11,366; or 7,119 major, minor, or minimal injuries
respectively estimated as occurring in PDO collisions. Because we need to transfer all
injuries from the revised PDO category we transfer 11,878 collisions (the number needed
to transfer all minor injuries based on the average characteristics of injury collisions), the
vehicles by damage severity involved in these collisions, all (11,366) minor injuries and
the available major (637) and minimal (7,119) injuries.
Exhibit A-7 (a section from spreadsheet O2 in the model) illustrates the results of
these transfers among collision severity categories to adjust for fatalities occurring in
injury collisions and injuries occurring in PDOs. The result of these transfers is to
increase the number of fatal collisions by 12 (with a corresponding reduction in injury
collisions) and to increase the number of injury collisions by 11,878 (with a
corresponding reduction in PDO collisions). The total number of collisions is not affected
nor is the number of vehicles involved. However there is a redistribution of collisions and
motor vehicles damaged by collision severity, as well as an increase in fatalities and
injuries to reflect the better data available from the Coroner’s Office (fatalities),
MOH&LTC (major and minor injuries) and Chipman re-analysis (minimal injuries).
TNS Canadian Facts, Social and Policy Research 127