Since the Great Recession, concern over the impact of inequality on families has been on the rise. According to a study by researchers from Cornell University, income inequality is linked to child abuse and neglect.

The study, published in the journal Pediatrics, looks at all 3,142 American counties from 2005 through 2009.  This makes the study one of the most comprehensive of its kind and the first to target child abuse in counties with high-income inequality, according to the press release announcing the results.

"More equal societies, states and communities have fewer health and social problems than less equal ones - that much was known. Our study extends the list of unfavorable child outcomes associated with income inequality to include child abuse and neglect," said John Eckenrode, professor of human development and director of the Bronfenbrenner Center for Translational Research in the College of Human Ecology.

The researchers noted that 3 million children under 18 years of age, or about 4 percent of the youth population, are abused physically, sexually or emotionally or are physically neglected each year in the United States.

"We have known for some time that poverty is one of the strongest precursors of child abuse and neglect," Eckenrode said. "In this paper we were also interested in areas with wide variations in income - think of counties encompassing affluent suburbs and impoverished inner cities - and in the US there is quite a lot of variation in inequality from county to county and state to state."

Cornell researchers found that the damage done by maltreatment doesn't stop when and if kids graduate from school.

"Child maltreatment is a toxic stressor in the lives of children that may result in childhood mortality and morbidities and have lifelong effects on leading causes of death in adults," they wrote. "This is in addition to long-term effects on mental health, substance use, risky sexual behavior and criminal behavior ... increased rates of unemployment, poverty and Medicaid use in adulthood." Eckenrode noted that "reducing poverty and inequality would be the single most effective way to prevent maltreatment of children, but in addition there are proven programs that work to support parents and children and help to reduce the chances of abuse and neglect - clearly a multifaceted strategy is needed."