**Background: Researchers studying psych symptoms in kids took advantage of a "natural experiment" that occurred when a tribe opened a casino which provided income to previously poor tribal members.
The researchers studied 1420 rural children (75% white, 25% indian) for 8 years.
About the study:
Each family was interviewed once a year. During these interviews, each child participating in the study was assessed for symptoms of mental illness and an adult from the household was interviewed regarding the family’s level of income. The families were classified into three groups: the persistently poor (below the federal poverty line both before and after the casino opened), the ex-poor (whose families moved out of poverty after the casino opened), and the never poor (whose families were above the poverty line both before and after the casino’s opening). The increase in income generated by the opening of the casino moved 14% of the families in the study out of poverty, while 53% of the families remained poor, and 32% were never poor.
The findings
The researchers found that prior to the opening of the casino, children in the persistently poor and ex-poor groups experienced more psychiatric symptoms than children who had never been poor. After the opening, certain psychiatric symptoms among the children who were no longer poor decreased to a level equivalent with that of children who had never been poor, while these psychiatric symptoms among those children who remained poor after the opening were unchanged.
This effect was noticed only among those children who displayed symptoms of behavioral and oppositional disorders, but not among children who displayed symptoms of emotional disorders, such as depression or anxiety.
...These results support a social causation theory for behavioral and oppositional disorders among children. In other words, poverty comes first.
After further analysis, the researchers also found evidence to suggest that the primary reason for the decrease in symptoms of mental illness among these children was due to improved parental supervision...
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