Physicians recommend that such visits begin as early as age 13, research shows.

CHICAGO — About half of American teenagers have never visited doctors without a parent or guardian present, despite recommendations that such visits begin about age 13, a study led by a Chicago researcher shows.

Dr. Jon Klein wanted find whether the American Medical Association's 1992 recommendation had any effect on teenagers taking an active role in their health care. The study showed that little has changed in 25 years.

"When we launched, we really were going back to that question of has it gotten any better," said Klein, head of pediatrics at the University of Illinois at Chicago Medical Center. "It's still only about half who have had private one-on-ones with a clinician."

The study, published in the Journal of Adolescent Health, surveyed adolescents and their parents, exploring at what age they think children and teenagers should begin to meet privately with doctors. He realized early on that key to a parent's understanding of why doctors want to speak with teenagers alone is explaining that it's so teenagers can take some ownership of their health.

"They still need their family's involvement, but a good way of phrasing it might be, 'When do you think your son or daughter will be ready to have some responsibility surrounding his or her medical care?'" Klein said. "When you put it that way, most parents are less oppositional about it because you've identified an opportunity for their child to grow."

The most surprising finding for Klein was that both teenagers and parents seem open to private or semi-private visits between doctor and teenager. They even agree as to the age this should happen, often suggesting either at 16 or 18 years old, Klein said.

"That is in contrast with what clinicians would prefer, which is about 13 years old, on average," he said.

Klein believes most survey respondents say 18 is the ideal age to make this shift because of the importance placed on the age in legal definitions in the U.S. But it is an arbitrary age, he said. An 18-year-old is not suddenly more mature, he said.

On the contrary, there are many reasons a doctor would want to begin discussing topics such as mental health, sexual and reproductive health and exposure to drugs, alcohol or tobacco as early as 11 or 12 years old, Klein said.

"It really is about prevention," he said.

"Eighteen is not a magic number in terms of physical or cognitive development," he said. "Fourteen or 15 is more often when a teenager exhibits the ability to think about things differently and to understand long-term consequences to actions. The ability to then make good decisions continues to evolve even through the 20s."

Dr. Cora Breuner of the Seattle Children's Hospital and a chairwoman for the Adolescence Committee of the American Academy of Pediatrics agreed. She said doctors need to talk with teenagers earlier, not just to ask questions and provide information, but at a key point.

"Let's face it, kids have done some stupid things before they turn 16. It's not best to do it after the horse is out of the barn," she said.

Both Klein and Breuner want parents to understand doctors are having age-appropriate conversations. When discussing HPV vaccinations, which can help prevent certain types of cancer, it is imperative to give the vaccine before a teenager is potentially infected, meaning well before the child is thinking about having sex.

"I think there's a myth that the provider is going to tell the kid it's OK to have sex or drink, and that's not what we're saying to them at all. We actually discuss how much sleep they're getting versus what they may need at any given age, texting and driving and how it is never OK, how many hours they spend in front of a screen, what to do if they forget to wear their bike helmet, or are being bullied or cyberbullied," she said.

In his experience, Klein said, only about 1 in 100 or 1 in 200 parents will speak out against a private visit between teenager and doctor or a semi-private visit — say the parent is present for the physical exam, and then asked to step out of the room.

Few teenagers share their decision to become sexually active with a parent, he said. But to ensure that they have the information they need about preventing an unwanted pregnancy or avoiding a sexually transmitted disease, it is important that doctors properly educate teenagers on their reproductive health. Klein said the study shows parents and teenagers are more often on the same page about that need than one might expect.

"Most parents and teenagers kind of do see it the same way," Klein said. "Teenagers learn values from their family, so families where there's good communicating, teenagers are likely to have absorbed some of that."

Breuner is a professor, making her partially responsible for some of the dozens of hours of study medical students will dedicate to learning how best to speak with teenage patients. They can spend up to 30 hours in one year going through role-playing scenarios with hired teenage actors, she said.

It's a good idea to post a sign in a doctor's office lobby indicating that teenagers will start having one-on-one time with doctors, to make parents aware of what's coming.

"There's nothing more frustrating than to be blindsided," Breuner said. "It's really not cool, so we have to, as teachers of doctors, teach them how to do this without alienating and terrifying the kids.

"There is a lot at stake in us getting it right. They deserve to be heard, they deserve to have a voice and they deserve to be able to talk to their provider alone," Breuner said.