The shortage of organs for transplant continues to grow, despite years of work to get more donors on board.

Facebook jumped in this month by making organ-donation status something you could add to your profile. And the social media giant made it easy to connect with a registry to sign up as a donor.

Federal law bans payments for organs. But given the need, we wondered what Americans thought about compensation for three kinds of donations that can be made while people are alive: kidneys, bone marrow and a portion of liver big enough to help someone whose liver is failing.

So we asked 3,000 adults across the country as part of the NPR-Thomson Reuters Health Poll, and here's what they told us.

If compensation took the form of credits for health care needs, about 60 percent of Americans would support it. Tax credits and tuition reimbursement were viewed favorably by 46 percent and 42 percent, respectively. Cash for organs was seen as OK by 41 percent of respondents.

Among people who said some form of compensation was acceptable, 72 percent said it should come from health insurers, followed by private charities at 62 percent and the federal government at 44 percent.

For all forms of compensation, rates of support tended to fall among older respondents.

There's been longstanding resistance to compensating donors financially in this country. There are concerns about exploitation and also worries that even small amounts of compensation would undercut a system that depends on altruism.

But it may be time to reconsider, Dr. Stuart Youngner, a bioethicist at Case Western Reserve University's med school, told Shots. "I think the market has become such an important guiding principle in so many areas of lives, including health care, that it becomes harder to say why shouldn't a person who donates organs make some money too," he said. "Altruism is very, very important, but in this case the lives of people are very, very important."

After reviewing the results of our poll, Youngner said it would have been stronger if we had asked people whether or not they were registered as organ donors and then investigated how financial incentives might have influenced their decisions.

As it was, we asked about three different donations, and the results came in about the same. About 87 percent of respondents in favor of compensation though it was OK for kidneys. About 85 percent felt that way about livers, and 83 percent for bone marrow.

It seems worth noting that the 9th U.S. Circuit Court of Appeals i n March affirmed an earlier decision that compensating people for marrow cells drawn from their blood wouldn't run afoul of the federal law banning payment for organ donations.

OK, so let's say donors could be compensated. How much should it be? Thirty-seven percent of respondents said it should be less than $10,000, and 27 percent said it should be more than $10,000 and less than $25,000.

Finally, we asked if there is a difference between compensating people for organ donations compared with buying them outright. Around 40 percent don't see one. Sixty percent of people said compensation isn't the same thing as a purchase.

"It's clear they're saying there is a difference," Dr. Ray Fabius, chief medical officer for Thomson Reuters' health unit, told Shots. And, overall, the results show that a majority believes "any living donor should be recognized, and it should be handled by insurance companies," he said.

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