WISQARS™ Cost of Injury Reports Help Menu
4.2 Calculation of Cost Estimates for Injury-Related Deaths
Cost Estimates Based on System-Provided Data Only
Each system-provided record representing an injury-related death was assigned an estimated unit lifetime medical cost and an estimated unit lifetime work loss cost. (For an injury-related death, lifetime medical cost refers to the medical cost associated with the fatal injury event.) The estimated unit lifetime medical cost was assigned according to the mechanism (cause) of injury, the place of death, and the age of the decedent. The estimated unit lifetime work loss cost was assigned according to the sex and age of the decedent.
Total cost estimates (lifetime medical, lifetime work loss, and/or combined) requested via the injury intent by mechanism classification scheme (Section 2.2) are calculated by summing the assigned unit cost estimates, across all records covered by the selected intent by mechanism category combinations (and also observing any specific geographic and/or demographic selections). Average cost estimates (per injury death) are then calculated by dividing each resulting total cost estimate by the number of fatal injury records contributing to it.
To facilitate the calculation of total and average cost estimates by body region and nature of injury, the assigned unit cost estimates were apportioned across the International Classification of Disease, 10th Revision7 (ICD-10) injury-related diagnosis codes appearing in each injury-related death record. For example, an injury-related death record with two ICD-10 injury-related diagnosis codes would result in an apportionment of 50% of the unit cost estimates (lifetime medical and lifetime work loss) to each such code (each would receive an apportionment weight of 0.5). The apportioned unit costs were correspondingly associated with body region by nature-of-injury category combinations via the translation of the ICD-10 injury-related diagnosis codes to these combinations (see Section 3.3 and Section 3.4).
Total cost estimates requested via the body region by nature of injury classification scheme (Section 2.2) are calculated by summing the apportioned unit cost estimates (see above) across all records covered by the selected body region and nature-of-injury category combinations, also observing any specific geographic and/or demographic selections. Average cost estimates (per injury death) are then calculated by dividing each resulting total cost estimate by the number of distinct cases contributing to it.
Cost Estimates That Combine System-Provided Data and User-Provided Data
The general framework for calculating cost estimates based on a combination of system-provided data and user-provided data is described in Section 4.1. The preliminary average cost estimates described in that framework are calculated according the procedures described immediately above; summary cost estimates are calculated as specified in the general framework.
Notes: Cost estimates (for fatal injuries) derived exclusively from system-provided data are reported in terms of U.S. prices indexed to the year 2010 (the current base year for WISQARS Cost of Injury Reports). However, cost estimates that combine system-provided data and user-provided data can be indexed to other years (see Section 2.4). By selecting the appropriate options in the user interface, state-level or regional-level cost estimates for fatal injuries can also be converted to region-specific or state-specific prices. For details regarding how cost estimates are converted from U.S. prices to region-specific or state-specific prices, see Section 4.4.
Apportionment of unit costs to support calculation of cost estimates associated with fatal injuries classified by body region and nature of injury is based in part on methodology developed by the National Center for Health Statistics. The SAS program that implements key components of this methodology may be viewed in this FTP directory (select the directory entry labeled IMD_10_Weighted_Total.sas).