Thanks for posting about this. I spent some time looking into bone marrow transplants a few years ago when a friend needed one.

I'm on the register, and I would donate if asked to. This is definitely at least partly driven by my personal experiences, but aside from that I suspect that for anyone who's not self-employed or doing direct work (or studying) it probably makes sense to join the register from a cost-effectiveness point of view.

Some useful considerations, at least some of which haven't already been mentioned by other commenters:

• If you're male and 16-30 your chance of donating at some point is around 1 in 170.
• In general, around 90% of donations are done though peripheral blood stem cell collection - as per Jorgen_Ljones' experience. This can take a few days to recover from, but isn't too invasive. The other 10% is through direct bone marrow collection, and requires general anesthesia. I think the trade-offs are quite different here for people who are self-employed or doing direct impact vs those working in a non-EA job, or earning to give. Personally I'm on the register and expect that I would be able to get some paid time off from work if I were asked to donate.
• In general, information sharing between the registers in various countries (e.g. Be The Match in US, Anthony Nolan in UK) is pretty good, and they tend to operate with volunteers who can transport bone marrow across countries when required.
• Only 60% of transplant recipients receive bone marrow from someone who is a 'perfect match'. Those other 40% lead a much higher risk of complications. So contributing to the register doesn't just lead to more transplants, but also to better transplants.
• I don't think the opportunity cost of signing up is an hour of productive time, at least in the UK. It's a 10m online form, a cheek swab, and walking past a post box.

Other data points from various sources that would be useful for a cost-effectiveness estimate on this:

• "Using conservative assumptions, the cost per life-year gained compared with no transplantation was US $16,346 (95% CI $8695, $38,006) for BM/PBSC transplantation" http://onlinelibrary.wiley.com/doi/10.1111/j.1524-4733.2007.00180.x/pdf
• "£37.7m was spent on donor provision facilitating over 1,300 transplants in the UK and abroad" https://www.anthonynolan.org/sites/default/files/AR_2017.pdf => It costs £29k/transplant (assuming 'facilitating' means total cost)
• In UK, cost is covered by NHS: https://www.england.nhs.uk/commissioning/spec-services/npc-crg/blood-and-infection-group-f/f01/#policies
• "The NHS England analysis suggests that funding second stem cell transplants could be cost-neutral. If patients do not receive transplants, they are given alternative treatments – further chemotherapy or palliative care – the costs of which are difficult to quantify as they are highly variable and depend on the patient’s circumstances. However, the policy working group of clinicians, commissioners, patients and stakeholder organisations, including Anthony Nolan, which advised NHS England on the decision, looked at examples of two patients who didn’t receive a second transplant. These patients were estimated to have incurred costs of about £130,000 over a one-year period." https://www.theguardian.com/commentisfree/2016/jul/28/nhs-cancer-second-stem-cell-transplants-funding
• "Thus we estimate the cost of a single cord blood transplant to be around £98,200 per patient, with cost up to 100 days post-transplant in the order of £72,000." ... "The cost of a transplant, and of alternative treatment, will be the same as for a cord blood transplant;" - Strategic oversight committee, 2014 report: http://studyres.com/doc/16711905/unrelated-donor-stem-cell-transplantation-in-the-uk => £10.1k/QALY at 9.7QALYs per transplant
• The estimated cumulative survival at 1 and 10 years were... 47% and 17.7%, respectively, for BM/PBSC recipients. http://onlinelibrary.wiley.com/doi/10.1111/j.1524-4733.2007.00180.x/pdf
• A recent study found that of patients who receive a second transplant, one in three achieved the five-year survival milestone. https://www.anthonynolan.org/news/2016/07/14/our-letter-following-nhs-england-announcement-funding-second-transplants (https://www.ncbi.nlm.nih.gov/pubmed/26631751)
• "Each transplant will result in a benefit of 9.7 QALYs. This is derived from survival rates for unrelated donor stem cell transplants (BSBMT 5th report to Specialist Commissioners) using the methodology reported above;" - Strategic oversight committee, 2014 report, p89: http://studyres.com/doc/16711905/unrelated-donor-stem-cell-transplantation-in-the-uk
• "The use of UK-sourced stem cells saves the NHS money. UK-sourced adult and cord blood donations are priced at £13,950 and £14,500 respectively. Imported adult donations are typically around £25,0004 and cord blood donations around £30,000." - strategic oversight committee, 2014 report

I've considered doing a cost-effectiveness estimate on this but haven't made time for it for various reasons; please let me know if you'd be interested in seeing it written up or writing it up. I have more info I can share which was shared with me privately.

I considered joining the UK equivalent of this some years ago. I opted not to:

• the website suggested that I should plan on the assumption that I may experience serious fatigue for 5 days after donating
• in order to do this I would need to inform my employer that I was on the list
• I already had a reputation at this stage for having an "extreme" interest in charitable activity

I had to weigh up definitely strengthening my employer's impression that I cared more about altruistic endeavours than my career against a 1-in-800 probability of doing something of value.

I don't get all the downvotes. Even if this turns out to not be very cost-effective (although maybe the post should be edited to highlight the initially missed considerations), it is helpful for us to see why as something to learn from.

It also makes the forum seem unfriendly to newcomers.

As an FYI, the expected benefit here is largely dependent on your ethnicity, and to a lesser extent, age:

1. White Americans/Europeans have very strong chances of finding a match (or many matches), so registering with that background means that you're likely less unique to the existing donor pool. Replaceability can often be high with this sort of background.

2. Those with other ethnic backgrounds can have much more difficulty finding matches. The less common your background (e.g., if you are mixed race, or from a less common background as found in the US, UK, and Germany (the countries which have the most donors)), the more likely it is that you'll be providing a donor where there is not otherwise a good candidate to be found, and thus actually sort of 'saving a life'.

3. Males under the age of 26 are typically considered the best donors, so you should more strongly consider this if you're a young, and/or male (although certainly many donors are used that don't match that criteria). If you're over 65, have a blood disorder, have received radiation, etc. you'll likely be told you're ineligible to donate to non-relatives.

While I don't have anything to add to other commentators on the cost-effectiveness estimate, I like this post for several reasons:

• In addition to the practical impact, thinking about bone marrow donation can be really good practice for figuring out the return on someone's time and energy (I could picture this being a trial task for an EA research org)
• It seems to me as though EA will best thrive if members try to be especially moral even beyond their careers and donations.
• This doesn't mean trying to achieve moral sainthood or enlightenment, but it does seem... coherent, I suppose, for people in EA to be the sorts of people who will clean up litter when they see it, help someone up who's fallen, be polite to store employees, and at least consider giving blood or bone marrow (assuming that the calculations work out).
• A community full of people who are in the habit of "doing the right thing" in small ways seems like it has a better chance of lasting for a long time, to the general satisfaction of its members. (Getting good at noticing when something is wrong and needs correction also has highly EA-relevant implications, e.g. around community health and taking action when someone's behavior is causing a lot of disvalue.)

I joined the registry in August 2012. I was asked to donate in April 2020 and did the donation in November 2020. Since I was already a registered organ donor (which should be opt-out, not opt-in… but I digress) it felt like the next logical step. Just a step up from giving blood.

I was actually surprised to be called upon, given the low odds of a match (1/430). And at one point in the process, it felt onerous and I nearly pulled out. But after thinking about how I would feel if I needed a transplant to possibly save my life, I went ahead with it.

The extraction was from my bloodstream (not needles in the pelvis, thankfully). But for this method, I had to receive injections of a drug that increased my bone marrow cell production. It gave me mild flu-like symptoms, which is normal.

It kinda sucked doing this during the heart of the pandemic, before the vaccine was even available to medical workers. I had to wear an N95 all day, and my girlfriend was not allowed in the room with me; usually, they allow a companion. I was also slightly worried about spending a whole day indoors with other people, which I wasn't doing at the time. The fact that it was a medical facility that was dedicated solely to cancer and had no COVID patients helped ease my mind.

It took about 6–7 hours in the clinic. I mostly read, watched videos, and snoozed between visits from the nurse. I required calcium supplements hourly since the centrifugal extraction process also pulls out calcium. My lips would get numb and tingly.

I paid for nothing. All of the tests, screenings, meds, the procedure, and travel costs were paid (including mileage, hotel room, and meals). 

As a bonus, I got a comprehensive health screening at a time when I didn't have great medical coverage.

All in all, I'm glad I did it. I think it's worth it for everyone to register given the low up-front investment. Odds are you won't be called. And if you are, you can always decide whether or not to do it at that time.

Yes, $1500 would be pretty competitive with GiveWell's top charities, and possibly better.

A few comments:

• Maybe some workplaces would consider giving you extra paid time off to do this. If not, you can use sick/personal days. If you're earning to give or otherwise don't do direct work, then the lost time might not be much of a loss at all.
• Does the time estimate include recovery time in bed?
• The estimate doesn't really consider the counterfactual. You'd want to know the probability that the person you would have helped (or another person in their place) would have died had you not donated. That probability is not 1, because they might have been saved by someone else instead, and you would want to adjust the cost-effectiveness based on this probability. Maybe another way of putting it is this: what percentage of people who sign up for this actually end up donating? This won't give you the right probability I mentioned just before, but it will tell you something about it: if almost everyone who signs up ends up donating, then the probability that an extra person gets a donation if you donate is also close to 1.

Australian equivalent: https://www.abmdr.org.au/ (They say on this one that you could be asked to donate to someone anywhere in the world, as it's part of a worldwide network.)

I signed up for this a couple of months ago. Pretty simple process, probably the same one that's described above. My main worry was not dropping more than 1/4 of the swabs! (They need three, but give you four in case you drop one as it's invalid if the tip has touched any surface except the inside of your mouth.)

If each of those (on average) 800 matches were only 1% likely to donate if chosen, then the probability that none of them would donate would be very small, ~0.03%. The counterfactual expected impact would be much lower than just 1/800; it would be scaled down by a factor of 0.0003.

However, if each were only 0.1% likely to donate if chosen, then you're close to a 50% probability of saving an extra life (or helping an extra person) than would have been saved (helped) otherwise, which would actually be very cost-effective.