We learned last week that we underestimated the total cost of the Against Malaria Foundation’s insecticide-treated net distribution.

A nonprofit interested in reducing costs for its own model read our AMF review and contacted AMF and Concern Universal (AMF’s distribution partner in Malawi). The nonprofit representative noticed that Concern’s costs seemed lower than he expected, and he hoped that he could find a way to reduce his own organization’s costs.

Concern Universal’s response to the nonprofit representative’s request listed several categories of costs that we excluded in our cost estimate. We will release a full report about these costs once we have all the details and have put together a revised estimate.

In our view, it is a huge benefit of our transparency that people outside GiveWell are able to scrutinize the material we publish on charities and ask questions that lead us to catch errors. This allows us to improve our charity reviews as well as our overall process.

Update: A few people have asked us, “How likely is this to change AMF’s #1-ranking?” It almost definitely will not change based on this. Our back of the envelope estimate of the costs puts them at less than $1 per net, which would not change our bottom line.