Is the term 'NHS winter crisis' becoming more common?

“This term ‘winter crisis’, if we go back in time to when we had a Labour government, I don't remember that term ever showing up. It’s something that in the last few years, every year, someone says winter crisis, winter crisis.”

BBC Question Time audience member, 28 September 2017

The term “winter crisis” does seem to have become more common in the past few years.

A crude search for articles containing both "NHS" and “winter crisis” in a newspaper database since 1993 shows the term was relatively common in newspapers in the UK in the first five or six years of the Labour government (1997-2002). There was a big spike in the year 2000, the year of a serious flu outbreak.

“Winter crisis” was heard of very little after 2002, until it re-emerged as a common talking point under the Coalition and then Conservative governments from 2013 onwards.