Seattle is apparently not the only Effective Altruism group to talk about doing volunteering meetings, only to remember that the traits that make volunteering useful are almost antithetical to the traits that make it fun and doable to for a group on a drop-in basis. I am kind of hoping that blood donation can bridge that gap. So here’s my math on how effective donating blood is. The Red Cross estimates a single donation can save three people, but what they mean is “a single donation can go to three different people.” To get the actual value we need to see how many units of blood were donated and how many deaths they prevented.
The most recent data I could find was the 2011 National blood Collection and Utilization Survey Report (PDF), which couldn’t make it harder to do this kind of calculation if it tried. They were extremely loose with what “unit” referred to, so I’m going to stick with the whole and red blood cell transfusions, so my numbers are consistent. There were 15,721,000 units collected, of which 14,589,000 were deemed usable. 13,785,000 were used, of which 37,000 were directed to a specific patient, and 65,000 were self-donations, which are less effective for various reasons. The collections numbers don’t call out general vs. specific donations and the numbers are small, so I’ll just use the total number used. If some blood donations are also generating plasma and white cells in addition to the red blood cells counted here, that would only increase effectiveness.
A single donation is one pint. Health and Human Services fails to define what they mean by unit, but it appears to mean “whatever you get from one donation after some filtering“, so let’s assume it’s 1:1. The average recipient receives 2.75 units. If you assume each person who received a transplant would otherwise die (supported by this sourceless FAQ), that means each donation saves ~1/3 of a life (discounting for donations that are rejected). Using GiveWell’s $5,000/life number, that’s still equivalent to donating $1,667. That is overstating the case, because some portion of recipients (I can’t find out how many) have diseases like sickle cell anemia that require chronic transfusions, and the fair thing is to count their lifetime transfusion count, not their per treatment count. To get an upper bound I’ll use the Red Cross’s number that a car accident victim can use up to a 100 pints of blood, which means each donor saves 1% of that life, which is equivalent to $50 to an extremely effective charity.
But the question isn’t “what is the average value of donated blood?” but “what is the marginal value of your potential donation?” I can’t find any direct numbers for this, but we have the following evidence:
- Very little blood is thrown out.
- People are spending lots of time and money developing artificial blood substitutes. Despite this there are no generally accept substitutes for blood’s oxygen-carrying capacity.
- The Red Cross spends a lot of time and money harassing people to donate. They called my parents’ house for years after my one donation (I’m O-).
- Some blood is able to reach the “too old” state, but then used to ill effect, indicating lumpy supply or demand. Unless you can predict demand spikes you should use the average efficacy. If you can predict demand spikes, there are probably more effective things to do with that power.
So I’m just going to use the average effectiveness as the marginal effectiveness for now.
What are the costs to the donor of donating? The one time I donated it was high because I slept for the next two days. If you’re my friend Elena who went into shock after donating, it cost you days and several thousand dollars in ER visits. So it is probably not worth it for either of us to donate. But for a typical person with no side effects, it’s plausibly useful. If it’s replacing work time, then effectiveness depends on their hourly wage. Multiple websites list the time to donate as 60-90 minutes, which translates to a minimum psuedowage of $33/hour and a maximum of $1667. The average hourly American wage is $24/hour, although I would estimate the average wage of people earning to give as somewhat higher than that. So that’s extremely plausible on its face. But if the time isn’t coming out of work, and is made rewarding to the participant, blood donation is hugely effective. This suggestions that an event that induced people to donate without replacing work would be effective, more so if it could be made into a positive experience. So a blood donation event could be a huge win for an EA event.
[Side note: if you decide to do this yourself, I would recommend donating anywhere but the Red Cross if at all possible. I’m going to try for Bloodworks NW, because if I get enough people they will send a truck and we can make it an actual party]

