A 10-year-old Pennsylvania girl in need of a lung transplant has once again focused our attention on the severe shortage of organ donors. Now comes a study that shows social media can improve the numbers, at least in the short term.

Many aspects of organ donation, particularly the allocation of donated organs, are contentious and involve significant ethical dilemmas. Getting people to sign up to be donors, however, is an obvious good with only one critical barrier: inaction. Most of us think it’s a good idea to do it, but we just don’t get around to signing up.

According to a report released this week, Facebook launched an effort more than a year ago to encourage its members to become organ donors. The effort grew out of discussions between Facebook’s Sheryl Sandberg and former classmate Andrew Cameron, a transplant director at Johns Hopkins University School of Medicine.

When Facebook created a way for members to share their organ donor status online in May 2012, 100,000 people took advantage of it, and 33,000 signed up with their state registries for the first time.

According to a study released Tuesday from the American Journal of Transplantation, 13,000 people in 44 states signed up on the first day of the Facebook project, compared with the typical 600. The report said the number declined over the following weeks, but stayed far higher than the previous average for the one-month study period.

Cameron, the study’s author, said more than 600,000 people in 17 countries have changed their profiles, but there are no figures to show how many of those represent new donor registrations. Also, there’s no data to show if any lives have been saved by the effort. Still, bringing attention to the need has value, and Facebook’s effort clearly made at least a short-term difference.

With 18 people dying every day for want of a donor, the need couldn’t be more obvious. Oregonians can register by contacting the Oregon Department of Motor Vehicles or the website of Donate Life Northwest at www.donatelife nw.org.