Validation of ICD-10-AM coding of mental health, drug and alcohol conditions in trauma patients NGUYENTU QUAN 2018 Mental health, drug and alcohol conditions are factors that increase the risk of poor recovery outcomes after injury. Administrative data coded from medical records are commonly relied upon in population studies of injured people to measure these conditions. But these data may be subject to biases, since they can be collected for purposes other than research. This thesis compares the recording of mental health, drug and alcohol conditions in severely injured people in administrative data and medical records, in order to determine whether there are any differences between the two alternative data sources for predicting poor outcomes after injury.