Until recently, the narrative surrounding foster care and children’s health assumed that the physical and mental health issues kids experienced stemmed from the traumas that landed them in foster care–such as abuse or neglect. Then, the authors of a new study, published November 2016 in Pediatrics, realized that no clinical research compared the health of children in foster care with the general population.

To remedy this oversight, the authors analyzed data from the 2011-2012 National Survey of Children’s Health that sampled 95,677 children. They compared the mental and physical health outcomes of children placed in foster care with those of children who had not spent time in foster care.

They found that children in foster care had more mental and physical health conditions than children who were never placed in foster care. They were twice as likely to have a learning disability, three times more likely to have hearing and vision problems, five times more likely to have anxiety, six times more likely to have behavioral problems, and seven times more likely to have depression. The greater likelihood of mental health problems persisted when comparing children who spent time in foster care with those in every other family type and those who experienced socioeconomic disadvantages. Health outcomes were worse for children adopted from foster care, however, which could be a result of remaining in the system for longer periods, until parental rights were terminated.

The researchers are careful to acknowledge that these data show association, not causality, but affirm, “The implications for pediatricians are also important because they suggest that foster care placement is a risk factor for health problems in childhood.”