Norway (admittedly a wealthy country with a v. good record on wealth distribution) uses a very similar method to JRF.

The most commonly used measure to define economic poverty in Norway is an income which is less than 60% of the annual median disposable equivalised household income.[1] Under this definition, 9.4% of Norwegian children aged between 0–17 years lived under the poverty line in 2014, which was up from 7.6% in 2006.[1] However, extreme poverty as a measure is not commonly used because it is almost non-existent in Norway.