I mean it can mean Nederlandse Hartstichting aswell (dutch heartfoundation) one of the few options given on the dutch wiki for NHS, the uk one is there obviously and a us one, national historic site. And you would think that a national institution for heartproblems (of which we see commercials nearly daily) would show up higher in the search result than something from abroad. So that just goes to show that the UK one is the most obvious answer and rather silly to ask for other things>
You wouldnt ask "Cleveland institute of art" to be accepted for CIA would you? Because central intelligence agency is the most obvious choice.
NHS - national honor society