"what does research show regarding race and ethnic differences in those who receive mental health services? "

Members of ethnic minorities don't utilize mental health services as often as other groups (specifically, Caucasians earning a middle-class income). This could be due to several reasons, including the fact that ethnic minorities are more likely to live in poverty. There have been connections to impoverished people and an inability to receive proper medical care (including, but not limited to, mental health services).