I'm especially interested in documenting existing literature on the topic.
I'm especially interested in documenting existing literature on the topic.
Probably depends on how you're reducing poverty...and how long-term your "long-term" is. Something like removing trade restrictions is likely to have very different long-term effects than distributing bednets. Even then I really don't have good answers for you on the nature of these differences.
You might want to check out the persistence studies literature. For example work by Nathan Nunn, who Will MacAskill references in this talk. This may not precisely align to what you're asking for, but Nunn has studies finding for example that:
Persistence studies seems a very interesting field and one I want to delve into more.
You may be interested in Superabundance by Marian Tupy and Gale Pooley. I haven't actually finished it, myself, but from what I've read so far they seem to argue that a greater population (which is a likely effect of poverty reduction) will, counterintuitively, increase wealth and prosperity since we'll have more workers, scientists, and inventors. I should mention, though, that it's published by a politically-conservative American think tank, so it may be somewhat biased in favor of limited government and against birth control.
"The graphs that show so much recent progress in the developing world—on poverty, on hunger, on education and infant mortality and life expectancy and gender relations and more—are, practically speaking, the same graphs that trace the dramatic rise in global carbon emissions that has brought the planet to the brink of overall catastrophe." -- The Uninhabitable Earth by David Wallace-Wells
I think the persistence studies stuff is the best bet. One thing to note there is that the literature is sort of a set of existence proofs. It shows that there are various things that have long-term impacts, but it might not give you a strong sense of the average long-term impact of poverty alleviation.