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My PITCHES trial prediction

January 26, 2019

With one exception, all outcomes will be negative

This is a trial with which I am closely involved. Registered here. Protocol published here.  I’m co-chief investigator, involved in all aspects of conception and design, and recruited many participants. I registered this prediction on 5 Jan 2019 after recruitment was completed, the database locked and while analysis by others was ongoing, but before I had seen any data.  This is rather late, and sceptical readers will need to contact the trial statistician if they doubt me. Nevertheless my prediction is date stamped on Aspredicted here. Note dates are in US form, month/day/year.

I predict that the trial will be negative with one exception, that the drug, ursodeoxycholic acid will reduce maternal itch. I further predict that this effect on maternal itching will be statistically significant, but that the size of the reduction will be so small that the average woman will judge the effect as not worthwhile.  The basis for this opinion is the pilot study (click here) published in 2012.

The reason for my prediction that all other adverse outcomes will not be significantly reduced is that I am sceptical about most treatments in general. In this case, although the treatment with ursodeoxycholic acid is popular, it is not underpinned by strong basic science.

To read more about Aspredicted.org click here.

Jim Thornton

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As Predicted

January 25, 2019

Did you really think that?

Aspredicted.org (click here), created in 2015 by the University of Pennsylvania, Wharton School’s “Credibility Lab” (click here), provides a simple way for researchers to make post hoc analyses clear by registering experimental details prospectively, and creating a short, time-stamped, pre-registration document to share and read.  By publicly registered their study designs, clinical triallists have done something similar for years. Aspredicted.org makes it easy for others to do the same.

The reason is that a registered experiment, conducted and analysed as planned, is far more credible than one which cannot prove that it didn’t stop when the result was positive or select the most favourable outcomes to report.

A suggestion

Experts and opinion leaders could raise their credibility in a similar way; by registering their opinions, and indicating in advance whether they would alter in response to new data. There would be advantages both for the expert, for the general public and for researchers.

Imagine, for example that an expert judged that an experiment had a design flaw. If the expert revealed their objection only after the results appeared, perhaps in a direction not favoured by the expert, readers might suspect the expert was finding fault because he did not like the result. By committing to believe the results of a well-designed experiment the expert is indicating that his mind is open to new evidence. His reputation would rise.

The general public would have an objective way to judge who to believe; those who were prepared to commit (or not) to new evidence in advance.

Researchers would also gain, if the practice became popular, because expert criticism  of experimental design would sometimes allow them to alter the experiment before it was too late.

I’ve made a start.  Here are my first five predictions.

PRISM (click here), CSTICH (click here), EPPIC (click here), PHOENIX (click here), PITCHES (click here)

I will explain more about each one over the coming days.

Jim Thornton

 

Founding a religion

December 30, 2018

Sleep or water?

Hugo Williams’ lovely poem Religion, from his 2009 collection West End Final, imagines setting one up. It’s a gentle homage to Philip Larkin’s even finer Water (1954). Isn’t Larkin’s “If I were called in to construct a religion”, a great opening?

Religion by Hugo Williams

If it were up to me
I would make use of sleep.
Going to church
would involve a flight of stairs
to a familiar bedroom,
where a broken alarm clock told the time.
The spreading of sheets,
the turning down of blankets,
would be followed by the drawing of curtains
in broad daylight,
the ritual of undressing.

Members of my religion
would be encouraged to sleep in
on Monday mornings
and any other morning they felt like it,
with no questions asked.
Sleep notes would be provided.
Couples would be authorised
to pull the covers over their heads
and spend their days tucked up
in cosy confessionals,
where all their sins would be forgiven.

Water by Philip Larkin

If I were called in
To construct a religion
I should make use of water.

Going to church
Would entail a fording
To dry, different clothes;

My liturgy would employ
Images of sousing,
A furious devout drench,

And I should raise in the east
A glass of water
Where any-angled light
Would congregate endlessly.

 

Nordic birth role models

December 24, 2018

Finnish grips, movement worries & induction

Nordic pregnancy and birth care is second to none. Midwives are well trained, and respected, and they keep accurate statistics. As a result maternal and perinatal mortality fell well before it did in the rest of Europe.  A Norwegian, Christian Kielland (click here) made the only important contribution to forceps design since Smellie introduced the pelvic curve.  A Swede, Tage Malmstrom (click here), invented the first workable ventouse. Iceland leads in genetic studies. Finnish obstetricians realised the importance of antisepsis before Semmelweis (click here) and were the the first to notice that so called, “benign” cholestasis, might not be benign after all (click here). I’m a fan.

Anglo Saxon obstetricians and midwives in contrast were slow to embrace evidence-based medicine, for which they were famously awarded the wooden spoon by Archie Cochrane in 1979 (click here). But we’ve improved. In England today it would be almost unthinkable to introduce a new way to deliver the head in the hope that it reduced vaginal tears. Imagine if obstetricians got the idea that encouraging women to call in urgently after the slightest alteration in the way their baby moved, or that inducing birth a week early, reduced stillbirths. Enthusiasts would be shown the relevant Cochrane reviews (click here, here and here), told to find out if the issue mattered to patients (click here) and if so, to test their hypotheses in randomised controlled trials. Claims to have discovered better ways to give birth or manage pregnancy, on the basis of historical or non-randomised controls, are met with derision in the UK. And that’s as it should be. Pregnant women have suffered enough from good ideas introduced with the best intentions.

But wait. Some Finns and Norwegians (click here) recently claimed that pressing on the mother’s perineum during birth using the “Finnish grip” (click here) prevented anal sphincter tears. Swedes, who let the head crown in the usual way, beat themselves up for not doing it (click here). Another group of Norwegians told women to report urgently, day or night, the slightest change in their baby’s movements and claimed to prevent stillbirths (click here). The Danes argued that a doubling of induction had done the same (click here).

And a funny thing happened. Instead of reminding the “Finnish grippers” that the rather similar HOOP (Hands On Or Poised) trial (click here) had shown no effect on perineal tears, and the “movement change worriers” that a large fetal movement counting trial had shown no effect on stillbirths (click here), the Royal Colleges of Obstetricians, and of Midwives, pushed both interventions as part of their “Obstetric Anal Sphincter Injury” (OASI) (click here) and “Saving Babies Lives” (click here) care bundles. They didn’t need to push induction. UK induction rates soared without help. The ideas had come from Scandinavia, and normal critical faculties switched off.

Fortunately not everyone was so gullible. Jane Norman and her colleagues tested the “make everyone worry about any alteration in fetal movements” hypothesis and showed that it was not only ineffective but harmful (click here and here). Now we’ve just gotta figure out how to stop doing it!

Bill Grobman and his colleagues in the US tested the “induce everyone hypothesis” and found that it didn’t reduce bad baby outcomes as much as hoped, although surprisingly, it appeared to reduce Caesareans (click here). More trials needed.

No-one seems to be doing a decent trial of the “Finnish grip” yet, although the OASI care bundle is getting push back from midwives on Twitter. Forgive the pun! Hopefully someone will do one soon.

Nordic obstetrics is great. But we should judge their ideas by the standards we require of anyone else.

Jim Thornton

Congratulations on your new baby

December 11, 2018

Now we do a rectal examination

The OASI (Obstetric Anal Sphincter Injury) Care Bundle, endorsed by the Royal Colleges of both Obstetricians & Gynaecologists and Midwives (click here and here) recommends a digital rectal examination after every normal birth “even if the perineum appears intact”. The idea of such an intrusive procedure, at such a sensitive time, is to diagnose unrecognised external anal sphincter tears. But it makes no sense.

The external anal sphincter is a ring of muscle, about as thick as a finger, which maintains continence. If there is a perineal tear or episiotomy, the sphincter is usually exposed, and a trained midwife can either see a tear directly, or palpate it.  Such injuries affect 2-5% of vaginal births, and examining for them in the presence of a perineal tear is uncontentious, because immediate repair is recommended.

In contrast, in the absence of a visible injury, anal sphincter damage is rare. One group (click here) found no cases among 291 women examined later by endoanal ultrasound. (Seven percent had evidence of a “non intact” internal sphincter, but that is a thin layer of impalpable muscle fibres adjacent to the anal mucosa; no-one thinks you can diagnose damage to that that by rectal examination.)

Moreover, if the perineum is intact, palpation is an imprecise way to diagnose sphincter injury, because skin and the transverse perineal muscles lie in the way. Few midwives or doctors are trained to identify an anal sphincter tear when the perineum is intact.

And what is the midwife supposed to do if she diagnoses this rare injury in a woman with an intact perineum? Call a doctor to incise the skin and repair the damaged sphincter? I don’t think so! Thirty years ago, I’m told, an idiosyncratic consultant in Leeds, who believed in the existence of occult sphincter damage, occasionally did just that, but he was a poor role model, ending his career in disgrace following an unrelated conviction for sexually assaulting his patients.

Pelvic floor exercises are recommended anyway, and there’s no point in bringing women back for extra postnatal examinations, because no-one recommends late surgery in the absence of symptoms.

Routine rectal examination in the presence of an intact perineum fails all the criteria of a useful screening test. Most midwives wisely don’t do it. Those that do, should stop.

Jim Thornton

 

Philip Larkin’s Koan

September 22, 2018

By Paisley Rekdal

Larkin never wrote a villanelle, but he featured in this one. Nor, though he wrote so much else about death, did he ever say that in a perfect universe we’d all be dead. It is the sort of thing he might have said, but death also terrified him. The koan I guess, a riddle without a solution, like the sound of one hand clapping.

Philip Larkin’s Koan

In the perfect universe of math it’s said
the world’s eternal aberration.
In fact, we should be less than dead,

math itself disrupted for matter ever to be read
as real. A thought so hard to fathom that The Nation
in its article on math has said

we lack the right imagination: the human head
will not subtract itself from the equation,
zero out the eager ego to be less than dead.

Did the numbers hunger for mistake, for fun upend
themselves to recalculate our infinite extinction?
And was existence meant for all, since it could be said

without our numbers others might have thrived:
the black rhinoceros, shortnose sturgeon—?
Articles of horn and scale both less and more than dead,

figurative dreams that now haunt us in our beds.
Memory’s another flaw in our equation. Was it The Nation?
I forget. Regardless, I know that someone said
in a perfect universe, we’d all be dead.

By Paisley Rekdal

Twenty Yards Behind

September 11, 2018

By Hugo Williams

In 1975 Wilko Johnson wrote “Twenty Yards Behind” for his band Dr Feelgood (click here).

“I’m walking twenty yards behind her/cause I love the way she shakes behind”

In 2014 Hugo Williams included this villanelle in his collection “I Knew the Bride” (click here)

All those things men find so intense,
watching her walking from twenty yards behind,
women take as the most tender nonsense.

Their appreciation isn’t a pretence,
but they couldn’t care less what kind
of strange things we find so intense,

so long as we enjoy the performance
and what we place in their hand
isn’t just some tender nonsense.

If we knew their true response,
as they threw their limbs around,
to all the things we find so intense,

we might experience detumuscence,
but at least we would understand
why they talked such tender nonsense.

With a greater degree of correspondence
we might not like what we found.
All those things men find so intense
women take as the most tender nonsense.

Hugo Williams

 

 

 

 

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