Nature – Researchers wrestle with a privacy problem – The data contained in tax returns, health and welfare records could be a gold mine for scientists — but only if they can protect people’s identities.

“…In the past few years, administrative data have been used to investigate issues ranging from the side effects of vaccines to the lasting impact of a child’s neighbourhood on his or her ability to earn and prosper as an adult. Proponents say that these rich information sources could greatly improve how governments measure the effectiveness of social programmes such as providing stipends to help families move to more resource-rich neighbourhoods. But there is also concern that the rush to use these data could pose new threats to citizens’ privacy…Many nations collect administrative data on a massive scale, but only a few, notably in northern Europe, have so far made it easy for researchers to use those data..”