Please have a look at:

Bakhtiari, S. (2011). Microfinance and poverty reduction: some international evidence. International Business & Economics Research Journal (IBER), 5(12).

Dr Mohammad Yunus, founder of Grameen Bank (a Nobel Peace prize winner) was recompensed for his efforts in demonstrating the role and viability of microfinance in reducing poverty. Perhaps his published work may reflect the sought after evidence.

There are some RCT evaluating impact of microcredit on borrowers for example: Banarjee, Duflo, Glennerster, and Kinnan (2009) and Karlan and Zinman (2009). You may also consult some other impact studies where they evaluate impact of saving on depositors for example: Duflo, Kremer, and Robinson (2009), Dupas and Robinson (2010), Brune, Gine, Goldberg, and Yang (2010) and Ashraf, Karlan and Yin (2006, 2010).

See Dowla and Barua, "The poor always pay back", based on the experience from Grameen.

Not to my knowledge. No systematic studies have been conducted.

Dear Mr. Seva:

Every person who works in Microfinance will tell you that it works fine (myself included), however it is not a panacea against poverty, because such a thing does not exist. Anyway, there have been measurings of the results Microfinance has as a tool agains poverty. Unfortunately, they are not 100% conclusive because there are many variables difficult to measure and compare.

Leaving that aside, there are things we know, for instance we know that a well managed program works better, we know that women are generally better clients than men, and that microfinance has an impact on the education of people involved.

Regards