In the linked study (doi:10.1136/bmj.d7031), Mills and colleagues attempt to quantify the cost to sub-Saharan African countries of investing in training but then not retaining doctors and nurses. They build on the limited analysis already conducted to assess the costs of “losing” scarce skilled staff to the developed world. They restate the debate about the real impact of the medical “brain drain.”1

A review of previous costing studies found that most lacked technical merit and focused on gross effects on African countries rather than net effects.2 Mills and colleagues try to look at some of the possible benefits that may accrue through remittance income and return migrants, but they focus primarily on assessing costs of training and the cost of lost return on investment as the health professionals leave the country that has funded their education.

According to Mills and colleagues’ analysis, developed countries have “saved billions of dollars” by recruiting ready trained health professionals without having to bear the training costs. They cite the World Health Organization’s 2010 code on international recruitment as a mechanism for achieving a more equitable balance of the costs of training between …