(AP) 
Some states declined to participate in medical experiments. Tennessee said its foster care rules generally prohibit enlisting children in such trials. California requires a judge's order. And Wisconsin "has absolutely never allowed, nor would we even consider, any clinical experiments with the children in our foster care system," spokeswoman Stephanie Marquis said.

Officials estimated that 5 percent to 10 percent of the 13,878 children enrolled in pediatric AIDS studies funded by NIH since the late 1980s were in foster care. More than two dozen Illinois foster children remain in studies today.

Some foster children died during studies, but state or city agencies said they could find no records that any deaths were directly caused by experimental treatments.

Researchers typically secured permission to enroll foster children through city or state agencies. And they frequently exempted themselves from appointing advocates by concluding the research carried minimal risk and the child would directly benefit because the drugs had already been tried in adults.

"Our position is that advocates weren't needed," said Marilyn Castaldi, spokeswoman for Columbia Presbyterian Medical Center in New York.

If they decline to appoint advocates under the federal law, researchers and their oversight boards must conclude that the experimental treatment affords the same or better risk-benefit possibilities than alternate treatments already in the marketplace. They also must abide by any additional protections required by state and local authorities.

Many of the studies that enrolled foster children occurred after 1990 when the government approved using the drug AZT - an effective AIDS treatment - for children.

Arthur Caplan, head of medical ethics at the University of Pennsylvania, said advocates should have been appointed for all foster children because researchers felt the pressure of a medical crisis and knew there was great uncertainty as to how children would react to AIDS medications that were often toxic for adults.

"It is exactly that set of circumstances that made it absolutely mandatory to get those kids those advocates," Caplan said. "It is inexcusable that they wouldn't have an advocate for each one of those children.

"When you have the most vulnerable subjects imaginable - kids without parents - you really do have to come in with someone independent, who doesn't have a dog in this fight," he said.

Those who made the decisions say the research gave foster kids access to drugs they otherwise couldn't get. And they say they protected the children's interest by carefully explaining risks and benefits to state guardians, foster parents and the children themselves.

"I understand the ethical dilemma surrounding the introduction of foster children into trials," said Dr. Mark Kline, a pediatric AIDS expert at Baylor College of Medicine. He enrolled some Texas foster kids in his studies, and doesn't recall appointing advocates for them.

"To say as a group that foster children should be excluded from clinical trials would have meant excluding these children from the best available therapies at the time," he said. "From an ethical perspective, I never thought that was a stand I could take."

Illinois officials directly credit the decision to enroll HIV-positive foster kids with bringing about a decline in deaths - from 40 between 1989 and 1995 to only 19 since.

NIH, the government health research agency that funded the studies, did not track researchers to determine if they appointed advocates. Instead, the decision was left to medical review boards made up of volunteers at each study site.

A recent Institute of Medicine study concluded those Institutional Review Boards (IRBs) were often overwhelmed, dominated by scientists and not focused enough on patient protections. An ethicist who served 22 years on such boards said they lack the resources to ensure the safety of foster children.

"Over the last half century, IRBs have basically broken under the strain of some of the structural changes in research," said Gregory E. Pence, a University of Alabama-Birmingham bioethicist.

The U.S. Office for Human Research Protections, created to protect research participants after the infamous Tuskegee syphilis studies on black men, is investigating the use of foster children in AIDS research. The office declined to discuss the probe.

NIH said it considers patient safety its top priority and awaits the outcome of the investigation. "If we find that patient protections need further strengthening, we will take action to do so," spokesman John Burklow said.

AP's review found that if children were old enough - usually between 5 and 10 - they also were educated about the risks and asked to consent. Sometimes, foster parents or biological parents were consulted; other times not.

"Our policy was to try and contact the (biological) parents because it was fairly common when we got done the foster kid would go back to the parents," said Dr. Ross McKinney, a pediatrics AIDS expert at Duke University.