Thanks for posting. I've been trying to find the best place to donate in blindness prevention for a few giving cycles now.
Intuitively, it feels like interventions without the direct goal of mortality prevention, like preventing blindness, could achieve nearly as much good over the years as preventing deaths.
In early effective altruism it was common for people to give the example of deciding between donating to fund the training of guide dogs in wealthy countries or to reduce blindness in very poor countries. For example, here's what Giving What We Can used to say:
For example, suppose we want to help those who are blind. We can help blind people in a developed country like the United States by paying to train a guide dog. This is more expensive than most people realize and costs around $50,000 to train a dog and teach its recipient how to make best use of it. In contrast, there are millions of people in developing countries who remain blind for lack of a cheap and safe eye operation. For the same amount of money as training a single guide dog, we could completely cure enough people of Trachoma-induced blindness to prevent a total of 2,600 years of blindness.
That writing went up sometime in 2011 or earlier, and I think it's where this comparison entered proto-EA, but if you know of earlier usage I'd be curious!
Over time, however, EAs have mostly moved away from this comparison. Instead global poverty EAs are more likely to give comparisons like:
What these have in common is that there are charities working in these areas with strong evidence to support their cost-effectiveness. With GiveDirectly you can send money to people who are living on under $1/day, or with the Against Malaria Foundation you can provide bednets that cut malaria deaths in ~half, at around $5k per life saved (~$100/QALY).
On the other hand, while GiveWell and other EA groups have looked into vision surgery, there are no high quality evaluations.[1] What do you do if you say something like "while a guide dog costs $X you can restore someone's sight for $Y << $X" and someone asks where they can donate to make that happen? Much better to give actionable comparisons.
You might think of Hellen Keller International, another GiveWell recommendation, but looking at their cost-effectiveness model, GiveWell is primarily rating it highly for mortality reduction. Looking at their vision benefits writeup and BOTEC, linked from the cost-effectiveness model, most of the supplementation is going to people who wouldn't otherwise become blind: yes, it's two pills for ~$2.70, but if I'm interpreting GiveWell's rough estimate correctly only 1:1,100 people who get the pill would otherwise become blind, and the supplementation isn't 100% effective, so it ends up being about $3k to prevent a case of blindness this way. (more)
According to this (not that rigorous) paper, cataract surgery can cost about $300. It improves vision and sometimes prevents blindness. Even if it's not as cost-effective as a GiveWell-recommended charity, it can still illustrate the point about guide dogs.
As someone who has thought about cost-effectiveness, I agree that comparing willingness-to-pay-for-a-QALY/life is a more robust point. But for people who haven't thought about this much, the more visceral preventing-blindness comparison might be better.
Maybe it would be worth someone checking that cataract-surgery charities like Sightsavers are passably cost-effective.
While it can illustrate the point I think there are two main issues:
If someone does get excited about what you're saying and wants to donate, we don't have anywhere with good evidence to recommend.
We shouldn't put much stock in numbers like "$300/surgery" unless there's been a good evaluation: it's very common that you end up with much lower benefits than expected per dollar once you start digging in. For example, perhaps existing funders already cover the cases where the surgery would prevent blindness, charities aren't willing to focus on the people with the worst vision, or the life expectancy of recipients is low because cataracts develop late in life.
Note that GiveWell did actually recommend Sightsavers (before their 2022 criteria changes), but for their deworming program, not their vision work.
They also looked into cataract surgery quite a bit in 2017 but didn't end up with anything to recommend.
Agree.