Apples and Jackfruit?

As has been discussed on this blog before, the Economist wrote a piece on the Partial Marvel of Microfinance, as evidenced by two recently completed impact evaluations. One was conducted by the Centre for Micro Finance in the slums of Hyderabad India, while the other was conducted by Innovations for Poverty Action in the peri-urban areas surrounding Manila. Both studies used rigorous research design, which included randomization, and both aimed to tease out the impact of microcredit on borrowers and on local economies. Yet, after reading the two resultant papers, I wonder if it's a stretch to swirl the results of the two studies together into a single analytical cocktail - as the Economist and no doubt others have done. Are we really comparing apples to apples here? Or, to incorporate one of my favourite Indian fruits, is it more like comparing apples and jackfruit? Here are just a few reasons I believe they are different.....

1. Clients in the Philippines earned above the national average; those in the slums of Hyderabad earned below the national average
   
2. Clients of the First Macro Bank in the Philippines went through at least two rounds of screening (including credit scoring!) before being accepted. They actually had to own a business in order to even be eligible and they had to fill out an application form; Indian clients did not undergo rigorous screening nor were they required to own a business.
   
3. Clients in the Philippines received an individual liability loan tenured over 13 weeks; Spandana clients in India received a group liability loan spread out over a year
4. First Macro Bank offers a slew of credit and savings products to clients (though this diversification of products is not mentioned in the Philippines study); Spandana offered credit only
   

Obviously, each new impact evaluation of microfinance adds weight to the body of evidence that we use to understand how the poor are effected by financial services. But at the same time, I hope that we as researchers, and the audience who reads our work, stay mindful of vast contextual variations between projects. Just because research methods are similar doesn't mean the fruits of our labour are congruent; though apples and jackfruits can certainly complement each other. With that I think I'm going to go make myself a fruit salad and call it a night.....

The Miracle of Microfinance? Duflo, Banerjee et al
Expanding Microenterprise Credit Access Karlan and Zinman