To measure the relative severity of the mental health care shortage from one region to the next, we used a metric that we call the shortage quotient. This quotient compares a region's share of the national mental health practitioner deficit against that area's share of the overall national population that live in shortage areas. For example, if a specific region had a psychiatrist deficit that was 4% of the national shortfall, and that region's population accounted for 5% of the national population that lived in mental health care shortage areas, then its shortage quotient would be 0.80 (4% divided by 5%). A shortage quotient below 1.0 would mean an region's psychiatrist shortage would be less severe than the national average, whereas a shortage quotient above 1.0 would mean the region had a more severe shortage of psychiatrists than the national average.
As of August 2015, HRSA data indicates that, on a relative basis, the region with the most severe mental health care shortage was New England. Although most other regions had a bigger share of the national mental health practitioner deficit, the shortage in New England was proportionately worse than all other regions. It's 4.7% share of the national mental health practitioner deficit is disproportionately large considering that the region only accounts for 3.2% of the national population living in designated mental health care shortage areas according the the HRSA. Excluding U.S. Territories, the mental health care shortage by region breaks down as follows: