In the U.S., states' Child Protective Services (CPS) investigate more than three million new cases of possible child abuse each year. In a small percentage of cases -- less than 10 percent -- the child will be placed into foster care.

A number of studies have looked into how children fare in the foster-care system. But a lot less has been known about that vast majority of kids who remain at home.

"CPS involvement in homes is actually really common in this country," said Dr. Kristine A. Campbell, a pediatrician at the University of Utah in Salt Lake City who led the new study.

It may be easy to make the assumption that those parents are "bad," she noted in an interview.

"But most of them are struggling with risk factors like poverty and poor social support, and may actually be trying to do well," Campbell said.

In her study, it did turn out that many families investigated by CPS were poor, or headed by a mother with depression or suffering abuse from her partner, for example. And at least some of those risk factors were still apparent three years after CPS came to the home for the first time.

The findings, which appear in the Journal of Pediatrics, are based on a national sample of 5,500 children who were followed after a first-time CPS investigation.

At the first CPS visit, 44 percent of families were below the poverty line. Just over 36 percent of moms or other caregivers said they lacked supportive people in their lives, and one-quarter of them had depression symptoms.

On top of that, 22 percent of women were suffering physical abuse from their partner.

All of those issues are also risk factors for child abuse. And Campbell's team found that for the most part, the prevalence of those risk factors did not change much over three years.

There were, however, some bright spots: Fewer women were being abused three years later -- down to just under 14 percent, from 22 percent.

And when CPS gave women a referral to domestic-abuse services, it seemed to make a huge difference, Campbell said. Among those women, the prevalence of partner abuse went from 54 percent to six percent.

"When they get some services, intimate-partner violence does go down dramatically," Campbell said.

And that's important not only for mothers themselves, she pointed out. Children often have to witness the abuse, or become victims themselves.

"We think the intimate-partner violence often precedes the abuse," Campbell said.

Research has also found that partner abuse often goes hand-in-hand with maternal depression, another risk factor for child abuse.

Of course, not all families investigated by CPS end up in any kind of program or service.

Of the families in this study, child abuse or neglect was substantiated in 28 percent of cases. And CPS gave service referrals to two-thirds of those families.

That meant one-third received no apparent help. "It's disappointing, but not surprising," Campbell said.

The reasons for the finding are not clear. But Campbell pointed out that CPS workers typically have "huge" caseloads and deal with situations where families may be less-than-welcoming.

"They have a very difficult job," she told Reuters Health.

That's where pediatricians can step in to help, according to Campbell. If they know a family has been investigated by CPS, they can follow up with the parents to see if they used referrals to any services.

"We can't make assumptions that everything's been taken care of," Campbell said.

The American Academy of Pediatrics now recommends that pediatricians screen mothers for postpartum depression.

Pediatricians do not routinely screen for domestic violence, but some will ask about it if they have reason to be concerned. There's no widespread routine screening because no one knows yet whether it's actually effective, Campbell explained.

What's "encouraging" in the current findings, she said, is that domestic-violence services did appear to help when they were offered.

Certain risk factors for child abuse, such as poverty, may be difficult to change, at least in the shorter term. "The system may not be able to fix everything that's wrong," Campbell noted.

But, she said, it's important to find out which risk factors can be changed, and then get those services to the families that need them.

SOURCE: bit.ly/KZmL1d Journal of Pediatrics, online April 4, 2012.

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