That matches what I've seen. In this case, though, they were tackling multiple issues to increase their chances of funding, not because they identified a common root cause.

My experience with Latin American NGOs and governments at J-PAL corroborates this: most programs lack cost-effectiveness. 

The trend of projects attempting to address multiple complex issues simultaneously is particularly concerning. When reviewing funding applications targeting child labor, deforestation, and wage improvement, most NGOs claimed they could tackle all three. This approach is fundamentally flawed — making significant progress on even one of these issues is challenging enough. IMO focusing on a single, well-defined problem is more likely to yield measurable impact than diluting efforts across multiple fronts.

There is also the Harvard Growth Lab. They work with governments to foster economic growth. There isn't a way to donate, but an actor to keep in mind. Their work is mostly based on the theory of Economic Complexity. 

Great writing. I do feel it conflates cost-effective solutions and "silver bullets". 

For some problems, there are silver bullets — vaccines is one example. For others, like "poverty among smallholder farmers in Uganda", I don't think we have found one. 

A silver bullet, to me, implies that all of our efforts should be going to that one solution. A quick mental model can be that the solution is orders of magnitude more efficient than the alternatives, so it almost doesn't matter how much you spend on the solution, it will still be cost-effective.

GiveDirectly doesn't clear the "silver bullet bar" as this story suggests (compare to vaccines vs smallpox). You might argue it is cost-effective, but that's a different story.

Very interesting argument. As someone fond of Bayesian modeling, I am almost always in favor of replacing point estimates with distributions.

GiveWell links to this paper in their CEA spreadsheet. Their recommendation is a discount rate of 4% for upper-middle-income countries and 5% for low-income countries. This recommendation seems to be based on three factors: Past growth of GDP, implied social discount rate, and projected GDP growth. All three, are measured with uncertainty and will vary by country. I think it would be very interesting to take that variability into account!