Staff from CHART analyzed hospital emergency department mental health claims data for 70 of the state's 71 acute care hospitals including a sub-focus on substance use disorder and self-harm data. The patient claims data were evaluated from three perspectives:

1. Volume of raw activity
   1. Presentation of a patient in a hospital emergency department
2. Use rates per 1,000 population
3. Five-year growth rate 2013-2017

Data were first analyzed where a mental health, substance use or self-harm diagnosis was present in any of the 25 diagnosis codes captured on the patient’s record. Therefore, the data include patients for whom mental health, substance use or self-harm was an underlying condition, but played a role in the emergency department visit.