It's a parent's worst nightmare: Your child is sick or injured, and isn't getting better anytime soon.

Psychologist Anne E. Kazak has spent much of her pioneering career trying to understand how children, families, and health-care workers cope with the grueling demands of long-term pediatric illness, which is now recognized as causing a version of post-traumatic stress.

Kazak is director of a new initiative, the Center for Healthcare Delivery Science, at Nemours/Alfred I. duPont Hospital for Children in Wilmington. The center studies the variables affecting pediatric health care - its delivery, safety, outcomes, cost, quality, and value. She recently was named editor-in-chief of American Psychologist, the journal of the American Psychological Association.

Kazak also is a professor of pediatrics at Thomas Jefferson University's Sidney Kimmel Medical College and an adjunct professor of psychology at the University of Delaware.

She recently spoke with us about her work.

What do you do?

Bad things do happen to children. A child one day seems perfectly normal and the next day is a little bit sick. The parent thinks it's just a cold or aches and pains. Then they are really shocked and thrown into a whole different course of life when they find out that perhaps those symptoms are due to a more serious illness. Most of my research has been in cancer. What we're interested in is the impact of that on the child, on the family, and how we in pediatric hospitals can make sure that we're reaching out and engaging and making this experience as tolerable as we can.

I sometimes don't want to tell people what I do at a cocktail party. It's a downer.

It seems so devastating. How can people possibly cope with a serious illness in their child?

Most kids and families actually have a remarkable ability to cope very well with extraordinary demands and situations, although that doesn't mean they don't suffer.

We do a good job in children's hospitals taking care of the kids' psychological needs. We have colorful drawings on the wall, a child-friendly environment, child-life specialists who do therapeutic-play activities with kids. We do our best to keep kids aware of what they're going through at a developmentally appropriate level, but also to protect them.

I sometimes give the example of my son, who, thankfully, has not had any serious illness. But he broke his arm at one point when we were away. Our friend had to take him to hospital. When they were leaving, he said, "That was fun. Can we come back?" He was happy because a child specialist had been playing catch with him with his good arm.

The adult is sitting there thinking, "I'm scared, I don't know what this is, I don't know how long this is going to take, I don't know what's ahead." In a situation that is medically more serious, where we think this might be cancer, we want to run more tests, parents get it. They get it intellectually, and they get it emotionally.

Why do you use the term "post-traumatic stress," and what are some of the symptoms?

In the late 1980s, a couple of us around the country were putting our heads together and thinking about it. I never really liked the analogy of the "war on cancer," but when you think about war - gearing up for battle, the potentially horrific things you might encounter - we found that a post-traumatic stress model did make sense in terms of describing the reactions of not only the kids, but also the parents.

You're faced with a potentially life-threatening situation. You're going to see other people who suffer. You're probably going to know children who die. You're going to keep coming back for more chemo or surgeries or hospitalizations.

One symptom is intrusive thoughts, which is a bit like a flashback. You're walking down the street, and all of a sudden you reexperience this traumatic event - diagnosis, pain, seeing another child in pain. Some of the procedures that kids have are difficult for the parents to see and participate in.

There also are avoidance behaviors. When something really bad has happened to you, you may choose to avoid things that remind you of it. The issue with illness and injuries are that you don't want people to avoid coming to the hospital.

Another set of symptoms is more physical. As something traumatic is unfolding in front of you, your heart rate increases, you feel a body tenseness, you may feel lightheaded or nauseous.

In the immediate days after a serious accident or a diagnosis of cancer in a child, the parents are almost universally experiencing some of these symptoms.

What gives you hope?

There's a lot we can do to help. Our Center for Pediatric Traumatic Stress - part of the National Child Traumatic Stress Network - has a website:

We're also working with a family foundation, Ryan's Case for Smiles, after their son who died of cancer. They sew and give kids special pillowcases when they're in the hospital. If you're an Eagles fan, you can have a pillowcase with the Eagles. If you like flowers, you can have flowers. You're handing a pillowcase to a kid. You can also hand a parent some information, so they can say, "This is interesting. I'm not alone in what I'm experiencing."

You recently were named editor of the American Psychologist. What do you hope to do?

We want the journal to reflect things that are important to our society. There's a lot of psychological knowledge about contemporary problems, such as violence, gun violence, the aftermath of shootings, mental-health issues, development problems such as autism, and more. I'd be hard-pressed to think of any kind of problem our society faces that there isn't a body of psychological research that could be drawn upon.