User community feedback drove a significant number of the changes seen in AIS 2015. The AIS dictionary has changed from landscape to portrait format and the amount of information for each line of AIS code was reduced to improve the ease of use for the coder. Many areas that were reported to be confusing or difficult to code in AIS 2008 were addressed. A significant number of injury descriptors were refined to better describe threat to life and impairment, and coding rules and guidelines were clarified or expanded to promote intercoder reliability. Injury descriptors for combat injuries were also included. Wherever possible any injury severity assignment changes were based upon available research evidence.
More specifically, the Head chapter includes a simplified method for coding diffuse axonal injury (DAI) as well as changes in coding other diffuse brain injuries. There is now a finer discrimination between loss of consciousness (LOC) and coma for patients with concussive type injuries. In the Face chapter 36 eye injury descriptors were removed because the fine level of discrimination they provided was rarely available in the medical documentation for coders. In the Abdomen chapter codes were added to more closely align with Organ Injury Scale (OIS) values developed by the American Association for the Surgery of Trauma. The Spine chapter was significantly revised in structure and in the level of injury specificity. The American Spinal Cord Injury Association (ASIA) Impairment scale has been included in the descriptors as a guide to assist in coding spinal cord injury deficit. The Extremity chapters have several new codes to preserve the capability of accurately coding injuries when less detail is available, as well as to better address closed degloving injuries and joint injuries. Heat-related injuries are now included in the Other Trauma section. This is not an exhaustive list of the changes but merely highlights some of the more important ones.
Perhaps one of the most significant improvements in AIS 2015 is the inclusion of comprehensive mapping between AIS 2008 and AIS 2015, making the merging or conversion of data from one version to the other simple, complete and universally standardized.