On May 2 this year, the topic chosen by Tim Harford in his ‘Undercover economist‘ column in the Financial Times was ‘Healthcare: the final reckoning‘. Tim is always interesting, but I don’t find him sound on health care economics and I disagreed with much of what he said in his column. Others, including Jeff Round of UCL and Mark Sculpher from University of York have challenged his comments, and I’ll simply endorse their statements on substantive issues. But I was intrigued by the background that Tim used to introduce a description and critique of QALYs. Apparently “The Qaly was dreamt up in 1956 by two health economists, Christopher Cundell and Carlos McCartney.” Now, if that is true, then I do apologise to those two economists, or to their friends and families if they are no longer with us, for what I am about to say. But as someone who knows a bit about health economics and especially about QALYs, I found it mysterious that I had never heard of these inventors or of their act of inventing. Apart from which, my understanding has been that QALYs were not invented in a single act by one or more named individuals. Instead, several different sources, in different intellectual disciplines and traditions, have contributed to their development.
I shared my query about this on twitter, after which James Raftery from Southampton University and I both investigated where this invention claim came from. Using some variations in wording, it is to be found in many places on the web. But it was obvious that the original source for all of them was a Wikipedia article entitled ‘Quality-adjusted life year’. That article even had a citation for this claim, a review paper in a Serbian medical journal. It seemed to me to be unlikely that such a paper would actually have uncovered a fact about QALYs unknown to anyone else, and indeed the paper has no reference for its claim, just offering it as fact.
Adding to the mystery, the Wikipedia article actually claimed that three health economists had invented QALYs, including someone called “Toni Morgan”. Digging a little further, I found that the third inventor had been added relatively recently. Apologies to Toni if he or she is real and did help to invent QALYs, but I couldn’t help noticing that this name is an anagram of “Giant Moron” and may therefore be made up. The Serbian paper citation had also been added relatively recently, and that paper was published long after the original invention claim was made on Wikipedia. My conclusion is that the claim was originally made in the Wikipedia article; that was the unreferenced source for the same claim in the Serbian paper; and the Serbian paper was then added as a citation supporting the Wikipedia claim. This problem of circularity in the generation of fake facts is well-known, and Tim Harford, in acknowledging his error, pointed to this comic from xkcd:
It’s a lesson in how referencing and citation can go wrong. More digging shows that someone in the University of Ulster posted the original invented invention claim in December 2010, and the same or perhaps another wag at the same institution added the third name in February 2014. I guess they did it for the lulz. I am not too dismayed by the fact that no-one who knows anything about QALYs picked this spoof up for over three years, since such people should not really be using Wikipedia as a source. However, as Chris Sampson has suggested elsewhere on this blog, health economists should be paying more attention to what is published about their discipline on Wikipedia. Mis- or dis-information should be corrected or challenged.
I’m pleased to say that Don Husereau from the Institute of Health Economics in Canada has now fixed the Wikipedia entry and given a much more accurate and sensible history. Let’s hope that this is the last we hear of Christopher, Carlos and Toni. Unless of course they are real, in which case I hope their pioneering work gets the recognition that it deserves.