Tuesday, 8 May 2018

Beware geeks bearing gifts

Poor old Jeremy. If he wasn't such a wazzock I'd feel sorry for him. As poisoned chalices go, his brief in the Commons the other day was a doozie. His PPS, or whoever does these things told him "There's been a bit of a whoopsie. A number of women in their late sixties, who were meant to be invited for their last smear test, weren't. As a result a few hundred may die – we can't be sure how many (if any)  but in any case we're jolly sorry. Now go out and tell the world."

What he didn't say, though, as Professor David Spiegelhalter said on More or Less last Friday, is that as a result of the absence of invitation, a few hundred may LIVE – we can't be sure how many (if any). Or, as Doctor Karsten Jørgensen summarized,
The evidence says that this is a close call, and increasingly the benefit is being brought into doubt and people are beginning to worry more about the harm.
But this is a nuanced problem, and experts are inclined to say things that are on the face of it quite upsetting to a non-expert's equilibrium, like "Of course, these people haven't died yet" (which invites the non-expert to add an unsaid "... so what's all the fuss about?" And given the length of the grass and the growth of the hedge, I don't have time to do it justice. But have a listen.

Before I sign off, though, I am reminded of a related programme in the Inside Health series a few weeks ago, about prostate screening (which I should say Doctor  Jørgensen said was a whole 'nother thing, because some sorts of screening have more hope of predicting the usefulness of possible treatments then others... but still). Dr Margaret McCartney warned about what the presenter called "a poor test" (screening for Prostate-Specific Antigen):
 ... [M]y heart sinks very often when we hear celebrities tell us that their life was saved by having a PSA test done... 
Because of the timing (early March 2018 programme) I assumed Dr McCartney was thinking of this celebrity endorsement:



But the Inside Health programme was a repeat, so Mr Fry just happened to have his head above the parapet at the time of that fusillade.
...And part of this is what’s called often the popularity paradox and that’s where bad tests become more popular.  The worse a test is, the poorer it performs, the more false alarms we create.  And the more false alarms are created the more treatment people have for conditions that were never going to become life threatening and were never going to harm people in any way.

Margaret McCartney on Inside Health 6 March 2018

Stuff happens... Live with it (until of course circumstances force you to suspend that operation in the land of the mortals.)


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