TEDGlobal 2011
Ben Goldacre: Battling bad science
Ben Goldacre: Boj proti slabi znanosti
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Vsak dan beremo poročila o novih nasvetih za zdravje, ampak kako lahko vemo, da imajo prav? Zdravnik in epidemiolog Ben Goldacre nam z veliko hitrostjo pokaže, kako je dokaze lahko popačiti, od očitnih prehranskih napotkov do komaj opaznih trikov farmacevtske industrije.
Ben Goldacre - Debunker
Ben Goldacre unpicks dodgy scientific claims made by scaremongering journalists, dubious government reports, pharmaceutical corporations, PR companies and quacks. Full bio
Ben Goldacre unpicks dodgy scientific claims made by scaremongering journalists, dubious government reports, pharmaceutical corporations, PR companies and quacks. Full bio
Double-click the English transcript below to play the video.
00:15
So I'm a doctor, but I kind of slipped sideways into research,
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Torej, sem zdravnik, ampak nekako sem pristal v raziskovanju
00:18
and now I'm an epidemiologist.
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in sedaj sem epidemiolog.
00:20
And nobody really knows what epidemiology is.
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Nihče zares ne ve, kaj je epidemiologija.
00:22
Epidemiology is the science of how we know in the real world
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Epidemiologija je veda o tem, kako v resničnem svetu vemo,
00:25
if something is good for you or bad for you.
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ali je za nas nekaj dobro ali slabo.
00:27
And it's best understood through example
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In najlažje jo je razumeti skozi primere
00:29
as the science of those crazy, wacky newspaper headlines.
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znanosti norih prismojenih časopisnih naslovov.
00:34
And these are just some of the examples.
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In to je samo nekaj primerov.
00:36
These are from the Daily Mail. Every country in the world has a newspaper like this.
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Tile so iz Daily Maila. Vsaka država na svetu ima takšne časopise.
00:39
It has this bizarre, ongoing philosophical project
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Ima ta bizarni, neprenehni filozofski projekt
00:42
of dividing all the inanimate objects in the world
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delitve vseh neživih stvari na svetu
00:44
into the ones that either cause or prevent cancer.
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na tiste, ki povzročajo, in take, ki preprečujejo raka.
00:47
So here are some of the things they said cause cancer recently:
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Tule je nekaj stvari, ki naj bi po njihovih nedavnih trditvah povzročale raka:
00:49
divorce, Wi-Fi, toiletries and coffee.
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ločitev, brezžični internet, kozmetika in kava.
00:51
Here are some of the things they say prevents cancer:
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Tule pa je nekaj stvari, za katere pravijo, da preprečujejo raka:
00:53
crusts, red pepper, licorice and coffee.
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skorja, rdeča paprika, sladki koren in kava.
00:55
So already you can see there are contradictions.
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Tu že lahko vidite, da obstajajo protislovja.
00:57
Coffee both causes and prevents cancer.
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Kava povzroča in preprečuje raka.
00:59
And as you start to read on, you can see
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In ko berete naprej, boste videli,
01:01
that maybe there's some kind of political valence behind some of this.
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da čez del tega morda visi nekakšna politična prevleka.
01:04
So for women, housework prevents breast cancer,
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Pri ženskah gospodinjsko delo preprečuje raka na dojki,
01:06
but for men, shopping could make you impotent.
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moškega pa bi nakupovanje lahko naredilo impotentnega.
01:09
So we know that we need to start
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Vemo torej, da moramo začeti
01:12
unpicking the science behind this.
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odkrivati znanost za vsem tem.
01:15
And what I hope to show
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In kar bi rad pokazal,
01:17
is that unpicking dodgy claims,
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je, da razkrivanje premetenih trditev,
01:19
unpicking the evidence behind dodgy claims,
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razkrivanje dokazov za takimi trditvami,
01:21
isn't a kind of nasty carping activity;
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ni nekakšno umazano dlakocepstvo;
01:24
it's socially useful,
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socialno koristno je,
01:26
but it's also an extremely valuable
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je pa tudi izjemno pomembno
01:28
explanatory tool.
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orodje za razlago.
01:30
Because real science is all about
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Kajti pri pravi znanosti
01:32
critically appraising the evidence for somebody else's position.
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gre za kritično ocenjevanje dokazov za stališča nekoga drugega.
01:34
That's what happens in academic journals.
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To se dogaja v akademskih revijah.
01:36
That's what happens at academic conferences.
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To se dogaja na akademskih konferencah.
01:38
The Q&A session after a post-op presents data
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Seja z vprašanji in odgovori po predstavitvi poteka operacije
01:40
is often a blood bath.
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je pogosto pravi pokol.
01:42
And nobody minds that. We actively welcome it.
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In to nikogar ne moti. To je dobrodošlo.
01:44
It's like a consenting intellectual S&M activity.
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Podobno je privolitvi v intelektualni sadomazohizem.
01:47
So what I'm going to show you
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Kar vam bom pokazal,
01:49
is all of the main things,
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so bistvene stvari,
01:51
all of the main features of my discipline --
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bistveni elementi moje discipline --
01:53
evidence-based medicine.
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medicine, utemeljene na dokazih.
01:55
And I will talk you through all of these
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Povedal vam bom o njih
01:57
and demonstrate how they work,
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in pokazal, kako delujejo,
01:59
exclusively using examples of people getting stuff wrong.
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izključno skozi primere tega, kako ljudje napačno razumejo stvari.
02:02
So we'll start with the absolute weakest form of evidence known to man,
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Začnimo z najšibkejšo obliko dokaza, kar jih pozna človeštvo,
02:05
and that is authority.
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to je avtoriteta.
02:07
In science, we don't care how many letters you have after your name.
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V znanosti nas ne zanima, koliko črk imate za svojim imenom.
02:10
In science, we want to know what your reasons are for believing something.
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V znanosti hočemo vedeti, kateri so vaši razlogi za verjetje v določeno stvar.
02:13
How do you know that something is good for us
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Kako veste, da je nekaj za nas dobro
02:15
or bad for us?
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ali slabo?
02:17
But we're also unimpressed by authority,
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Ampak avtoriteta nas pusti hladne tudi zato,
02:19
because it's so easy to contrive.
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ker si jo je tako enostavno izmisliti.
02:21
This is somebody called Dr. Gillian McKeith Ph.D,
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Obstaja nekdo po imenu dr. Gillian McKeith, PhD,
02:23
or, to give her full medical title, Gillian McKeith.
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ali, z njenim polnim medicinskim nazivom, Gillian McKeith.
02:26
(Laughter)
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(Smeh)
02:29
Again, every country has somebody like this.
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Ponavljam, v vsaki državi obstajajo taki ljudje.
02:31
She is our TV diet guru.
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Ona je naša gurujka TV diet.
02:33
She has massive five series of prime-time television,
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Ima pet ogromnih serij v osrednjem televizijskem terminu,
02:36
giving out very lavish and exotic health advice.
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kjer daje pretirane in eksotične nasvete za zdravje.
02:39
She, it turns out, has a non-accredited correspondence course Ph.D.
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Izkazalo se je, da ima doktorat na podlagi neakreditiranega tečaja na daljavo
02:42
from somewhere in America.
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nekje iz Amerike.
02:44
She also boasts that she's a certified professional member
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Hvali se tudi s tem, da je certificirana profesionalna članica
02:46
of the American Association of Nutritional Consultants,
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Ameriške zveze svetovalcev za prehrano,
02:48
which sounds very glamorous and exciting.
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kar se sliši zelo glamurozno in vznemirljivo.
02:50
You get a certificate and everything.
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Dajo vam certifikat in vse to.
02:52
This one belongs to my dead cat Hetti. She was a horrible cat.
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Tale pripada moji mrtvi mački Hetti. Grozna mačka je bila.
02:54
You just go to the website, fill out the form,
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Enostavno greste na njihovo spletno stran, izpolnite obrazec,
02:56
give them $60, and it arrives in the post.
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plačate 60 dolarjev in dobite ga po pošti.
02:58
Now that's not the only reason that we think this person is an idiot.
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To seveda ni edini razlog, zakaj mislimo, da je ta oseba neumna.
03:00
She also goes and says things like,
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Tudi govori stvari, kot so:
03:02
you should eat lots of dark green leaves,
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jesti morate veliko temnozelenih listov,
03:04
because they contain lots of chlorophyll, and that will really oxygenate your blood.
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saj vsebujejo veliko klorofila in to bo dodalo kisik v vašo kri.
03:06
And anybody who's done school biology remembers
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Toda vsak, kdor je v šoli imel biologijo, se bo spomnil,
03:08
that chlorophyll and chloroplasts
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da klorofil in kloroplasti
03:10
only make oxygen in sunlight,
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proizvajajo kisik samo na sončni svetlobi,
03:12
and it's quite dark in your bowels after you've eaten spinach.
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v vašem prebavnem traktu pa je, potem ko ste pojedli špinačo, dokaj temno.
03:15
Next, we need proper science, proper evidence.
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Potrebujemo pravo znanost, prave dokaze.
03:18
So, "Red wine can help prevent breast cancer."
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Torej, "rdeče vino pomaga preprečevati raka dojke."
03:20
This is a headline from the Daily Telegraph in the U.K.
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To je naslov iz Daily Telegrapha v Veliki Britaniji.
03:22
"A glass of red wine a day could help prevent breast cancer."
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"Kozarec rdečega vina na dan bi lahko preprečil raka dojke."
03:25
So you go and find this paper, and what you find
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Torej, greste prebrat tale članek in dobite
03:27
is it is a real piece of science.
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pravi primerek znanosti.
03:29
It is a description of the changes in one enzyme
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Gre za opis sprememb v encimu,
03:32
when you drip a chemical extracted from some red grape skin
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ko kemikalijo, odvzeto iz lupine rdeče grozdne lagode, kanete
03:35
onto some cancer cells
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na nekaj rakavih celic
03:37
in a dish on a bench in a laboratory somewhere.
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v posodici na klopci nekje v laboratoriju.
03:40
And that's a really useful thing to describe
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To je res uporabno za opis
03:42
in a scientific paper,
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v znanstvenem članku,
03:44
but on the question of your own personal risk
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a na vprašanje o vašem osebnem tveganju,
03:46
of getting breast cancer if you drink red wine,
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da bi dobili raka na dojki, če pijete rdeče vino,
03:48
it tells you absolutely bugger all.
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vam ne pove popolnoma nič.
03:50
Actually, it turns out that your risk of breast cancer
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Pravzaprav se izkaže, da se vaše tveganje za raka dojke
03:52
actually increases slightly
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rahlo poveča
03:54
with every amount of alcohol that you drink.
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z vsako enoto alkohola, ki jo popijete.
03:56
So what we want is studies in real human people.
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Torej, kar želimo, so študije s pravimi ljudmi.
04:00
And here's another example.
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In tu je še en primer.
04:02
This is from Britain's leading diet and nutritionist in the Daily Mirror,
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Tale je last vodilne diete in britanskega strokovnjaka za prehrano iz Daily Mirrorja,
04:05
which is our second biggest selling newspaper.
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ki je časopis z drugo najvišjo naklado pri nas.
04:07
"An Australian study in 2001
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"Avstralska študija iz leta 2001
04:09
found that olive oil in combination with fruits, vegetables and pulses
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je ugotovila, da olivno olje v kombinaciji s sadjem, zelenjavo in stročnicami
04:11
offers measurable protection against skin wrinklings."
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zagotavlja merljivo zaščito pred gubanjem kože."
04:13
And then they give you advice:
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In potem svetujejo:
04:15
"If you eat olive oil and vegetables, you'll have fewer skin wrinkles."
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"Če jeste olivno olje in zelenjavo, boste imeli manj gubic."
04:17
And they very helpfully tell you how to go and find the paper.
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In zelo prijazno vam povejo, kako pridete do članka.
04:19
So you go and find the paper, and what you find is an observational study.
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Najdete ga in ugotovite, da je šlo za študijo z opazovanjem.
04:22
Obviously nobody has been able
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Očitno nikomur ni uspelo
04:24
to go back to 1930,
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iti nazaj v leto 1930,
04:26
get all the people born in one maternity unit,
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dobiti vseh ljudi iz določene porodnišnice,
04:29
and half of them eat lots of fruit and veg and olive oil,
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polovica katerih bi jedla veliko sadja, zelenjave in olivnega olja,
04:31
and then half of them eat McDonald's,
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druga polovica pa hrano iz McDonaldsa
04:33
and then we see how many wrinkles you've got later.
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in potem bi izmerili, koliko gubic bodo dobili čez leta.
04:35
You have to take a snapshot of how people are now.
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Gre za trenutno sliko, kakšni so ljudje sedaj.
04:37
And what you find is, of course,
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In seveda ugotovite tudi,
04:39
people who eat veg and olive oil have fewer skin wrinkles.
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da imajo ljudje, ki jedo zelenjavo in olivno olje, manj gubic.
04:42
But that's because people who eat fruit and veg and olive oil,
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A to je zato, ker so ljudje, ki jedo sadje, zelenjavo in olivno olje,
04:45
they're freaks, they're not normal, they're like you;
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pošasti, niso normalni, taki so kot ste vi,
04:48
they come to events like this.
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prihajajo na dogodke, kakršen je tale.
04:50
They are posh, they're wealthy, they're less likely to have outdoor jobs,
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Elegantni so, bogati, manj verjetno je, da delajo zunaj,
04:53
they're less likely to do manual labor,
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manj verjetno je, da opravljajo fizična dela,
04:55
they have better social support, they're less likely to smoke --
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imajo boljšo socialno podporo in manj verjetno je, da kadijo --
04:57
so for a whole host of fascinating, interlocking
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torej zaradi kupa očarljivih, povezanih
04:59
social, political and cultural reasons,
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socialnih, političnih in kulturnih razlogov
05:01
they are less likely to have skin wrinkles.
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obstaja manjša verjetnost, da imajo gubice.
05:03
That doesn't mean that it's the vegetables or the olive oil.
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To pa ne pomeni, da je tako zaradi zelenjave in olivnega olja.
05:05
(Laughter)
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(Smeh)
05:07
So ideally what you want to do is a trial.
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V idealnem primeru torej hočete napraviti testiranje.
05:10
And everybody thinks they're very familiar with the idea of a trial.
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In vsi mislijo, da so dobro seznanjeni z idejo testiranja.
05:12
Trials are very old. The first trial was in the Bible -- Daniel 1:12.
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Testi so zelo stari. Prvi je bil v Svetem pismu -- Danijel 1:12.
05:15
It's very straightforward -- you take a bunch of people, you split them in half,
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Zelo neposreden je: vzamete skupino ljudi, jih razdelite na dva dela,
05:17
you treat one group one way, you treat the other group the other way,
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eno skupino obravnavate na en način, drugo pa na drugega
05:19
and a little while later, you follow them up
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in malo kasneje jih preverite
05:21
and see what happened to each of them.
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in ugotovite, kaj se je z njimi zgodilo.
05:23
So I'm going to tell you about one trial,
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Povedal vam bom o testu,
05:25
which is probably the most well-reported trial
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ki je verjetno eden tistih, o katerih so v britanskih novicah
05:27
in the U.K. news media over the past decade.
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v zadnjem desetletju največ poročali.
05:29
And this is the trial of fish oil pills.
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In to je test o tabletah ribjega olja.
05:31
And the claim was fish oil pills improve school performance and behavior
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Trdili so, da tablete z ribjim oljem izboljšajo uspeh in obnašanje v šoli
05:33
in mainstream children.
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pri povprečnih otrocih.
05:35
And they said, "We've done a trial.
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In rekli so: "Testirali smo jih.
05:37
All the previous trials were positive, and we know this one's gonna be too."
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Vsi prejšnji testi so bili pozitivni in vemo, da bo tudi tale."
05:39
That should always ring alarm bells.
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Take stvari bi vedno morale sprožiti alarm.
05:41
Because if you already know the answer to your trial, you shouldn't be doing one.
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Kajti če vnaprej poznate rezultat svojega testa, potem testa ne bi smeli opravljati.
05:44
Either you've rigged it by design,
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Bodisi ste goljufali namenoma
05:46
or you've got enough data so there's no need to randomize people anymore.
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bodisi imate dovolj podatkov, zato vam ni treba več delati naključnih vzorcev ljudi.
05:49
So this is what they were going to do in their trial.
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No, tole so želeli napraviti s svojim testom.
05:52
They were taking 3,000 children,
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Vzeli so 3.000 otrok,
05:54
they were going to give them all these huge fish oil pills,
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vsem so hoteli dati ogromne tablete z ribjim oljem,
05:56
six of them a day,
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po šest na dan,
05:58
and then a year later, they were going to measure their school exam performance
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in potem so nameravali leto dni kasneje izmeriti njihov uspeh pri izpitih
06:01
and compare their school exam performance
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ter ga primerjati
06:03
against what they predicted their exam performance would have been
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s pričakovanim uspehom, ki bi ga otroci dosegli,
06:05
if they hadn't had the pills.
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če ne bi jemali tablet.
06:08
Now can anybody spot a flaw in this design?
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Lahko kdo zazna zmoto v tem pristopu?
06:11
And no professors of clinical trial methodology
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In prosim, naj profesorji klinične metodologije testov
06:14
are allowed to answer this question.
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ne odgovarjajo na to vprašanje.
06:16
So there's no control; there's no control group.
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Torej, ni kontrole, ni kotrolne skupine.
06:18
But that sounds really techie.
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A to zveni precej tehnično.
06:20
That's a technical term.
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Gre za tehnični izraz.
06:22
The kids got the pills, and then their performance improved.
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Otroci so dobili tablete in njihov uspeh se je izboljšal.
06:24
What else could it possibly be if it wasn't the pills?
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Kaj drugega kot tablete bi lahko bilo razlog za to?
06:27
They got older. We all develop over time.
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Postali so starejši. Vsi se s časom razvijamo.
06:30
And of course, also there's the placebo effect.
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In seveda obstaja placebo učinek.
06:32
The placebo effect is one of the most fascinating things in the whole of medicine.
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Placebo učinek je ena najbolj zanimivih stvari v vsej medicini.
06:34
It's not just about taking a pill, and your performance and your pain getting better.
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Ne gre samo za jemanje tablete, kar povzroči, da se vaše delovanje izboljša in bolečina zmanjša.
06:37
It's about our beliefs and expectations.
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Gre za verjetje in pričakovanja.
06:39
It's about the cultural meaning of a treatment.
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Gre za kulturni pomen zdravljenja.
06:41
And this has been demonstrated in a whole raft of fascinating studies
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In to so dokazale številne izjemne študije,
06:44
comparing one kind of placebo against another.
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ki so primerjale različne vrste placeba med seboj.
06:47
So we know, for example, that two sugar pills a day
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Vemo, na primer, da sta dve tableti sladkorja na dan
06:49
are a more effective treatment for getting rid of gastric ulcers
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bolj učinkovito zdravilo za čir na želodcu
06:51
than one sugar pill.
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kot ena tableta sladkorja.
06:53
Two sugar pills a day beats one sugar pill a day.
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Dve tableti sladkorja premagata eno.
06:55
And that's an outrageous and ridiculous finding, but it's true.
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To je nezaslišana in smešna stvar, a tako je.
06:58
We know from three different studies on three different types of pain
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Iz treh različnih študij na treh vrstah bolečine vemo,
07:00
that a saltwater injection is a more effective treatment for pain
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da je injekcija slane vode bolj učinkovito zdravilo
07:03
than taking a sugar pill, taking a dummy pill that has no medicine in it --
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kot tableta sladkorja, tableta, v kateri ni zdravila --
07:07
not because the injection or the pills do anything physically to the body,
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ne zato, ker bi injekcija ali tableta imeli kak fizikalni vpliv na telo,
07:10
but because an injection feels like a much more dramatic intervention.
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ampak zato, ker je injekcija bolj dramatična intervencija.
07:13
So we know that our beliefs and expectations
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Vemo torej, da je z našimi verjetji in pričakovanji
07:15
can be manipulated,
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mogoče manipulirati,
07:17
which is why we do trials
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zato delamo teste,
07:19
where we control against a placebo --
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kjer kontroliramo s placebom --
07:21
where one half of the people get the real treatment
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kjer polovica ljudi dobi pravo zdravilo,
07:23
and the other half get placebo.
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druga polovica pa placebo.
07:25
But that's not enough.
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A to še ni dovolj.
07:28
What I've just shown you are examples of the very simple and straightforward ways
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Pravkar smo vam pokazali primere enostavnih in jasnih načinov,
07:31
that journalists and food supplement pill peddlers
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kako novinarji in krošnjarji s tabletami kot prehranskimi dopolnili
07:33
and naturopaths
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in mazači
07:35
can distort evidence for their own purposes.
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lahko izkrivijo dokaze v svoje namene.
07:38
What I find really fascinating
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Zdi se mi res fascinantno,
07:40
is that the pharmaceutical industry
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kako farmacevtska industrija
07:42
uses exactly the same kinds of tricks and devices,
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uporablja popolnoma iste trike in pristope,
07:44
but slightly more sophisticated versions of them,
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le v malo bolj prefinjeni obliki,
07:47
in order to distort the evidence that they give to doctors and patients,
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da bi izkrivila dokaze, ki jih dobijo zdravniki in pacienti,
07:50
and which we use to make vitally important decisions.
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in katere uporabljamo za sprejemanje življenjsko pomembnih odločitev.
07:53
So firstly, trials against placebo:
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Torej, prvič, testi s placebom:
07:55
everybody thinks they know that a trial should be
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vsak misli, da bi test moral biti
07:57
a comparison of your new drug against placebo.
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primerjava novega zdravila s placebom.
07:59
But actually in a lot of situations that's wrong.
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A v resnici je to v veliko primerih narobe.
08:01
Because often we already have a very good treatment that is currently available,
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Kajti pogosto že obstaja dosegljivo dobro zdravljenje,
08:04
so we don't want to know that your alternative new treatment
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zato nočemo, da bi bilo alternativno novo zdravljenje
08:06
is better than nothing.
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boljše kot nič.
08:08
We want to know that it's better than the best currently available treatment that we have.
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Hočemo vedeti, da je boljše od najboljšega trenutno dostopnega zdravljenja.
08:11
And yet, repeatedly, you consistently see people doing trials
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A vseeno, in vedno znova, stalno videvamo teste,
08:14
still against placebo.
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ki se primerjajo s placebom.
08:16
And you can get license to bring your drug to market
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In licenco za trženje zdravila lahko dobite
08:18
with only data showing that it's better than nothing,
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že s podatki, ki kažejo, da je boljše kot nič,
08:20
which is useless for a doctor like me trying to make a decision.
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kar je zame kot zdravnika, ki mora sprejeti odločitev, neuporabno.
08:23
But that's not the only way you can rig your data.
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A to ni edini način, kako lahko potvorite podatke.
08:25
You can also rig your data
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To lahko storite tudi tako,
08:27
by making the thing you compare your new drug against
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da za stvar, s katero primerjate svoje novo zdravilo,
08:29
really rubbish.
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vzamete nekaj res slabega.
08:31
You can give the competing drug in too low a dose,
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Konkurenčno zdravilo lahko date v prenizki dozi,
08:33
so that people aren't properly treated.
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tako da ljudje ne dobijo pravilne terapije.
08:35
You can give the competing drug in too high a dose,
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Konkurenčno zdravilo lahko date v previsoki dozi,
08:37
so that people get side effects.
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tako da pride do stranskih učinkov.
08:39
And this is exactly what happened
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In prav to se je zgodilo
08:41
which antipsychotic medication for schizophrenia.
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z antipsihotikom za shizofrenijo.
08:43
20 years ago, a new generation of antipsychotic drugs were brought in
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Pred dvajsetimi leti je na trg prišla nova generacija antipsihotikov
08:46
and the promise was that they would have fewer side effects.
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in obljubljali so, da bodo imeli manj stranskih učinkov.
08:49
So people set about doing trials of these new drugs
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Tako so se začeli testi tega novega zdravila
08:51
against the old drugs,
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v primerjavi s starim,
08:53
but they gave the old drugs in ridiculously high doses --
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a starega so dajali v absurdno visokih dozah --
08:55
20 milligrams a day of haloperidol.
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20 miligramov haloperidola na dan.
08:57
And it's a foregone conclusion,
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In vnaprej je jasno,
08:59
if you give a drug at that high a dose,
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da če date zdravilo v visoki dozi,
09:01
that it will have more side effects and that your new drug will look better.
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bo to imelo več stranskih učinkov in vaše novo zdravilo bo videti boljše.
09:04
10 years ago, history repeated itself, interestingly,
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Pred desetimi leti se je zgodovina ponovila, kako zanimivo,
09:06
when risperidone, which was the first of the new-generation antipscyhotic drugs,
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ko je risperidonu, prvemu antipsihotiku nove generacije,
09:09
came off copyright, so anybody could make copies.
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potekla patentna zaščita in so ga vsi lahko kopirali.
09:12
Everybody wanted to show that their drug was better than risperidone,
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Vsi so hoteli pokazati, da je njihovo zdravilo boljše od risperidona,
09:14
so you see a bunch of trials comparing new antipsychotic drugs
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in priča smo bili kupu testov, ki so nove antipsihotike primerjali
09:17
against risperidone at eight milligrams a day.
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z osmimi miligrami risperidona na dan.
09:19
Again, not an insane dose, not an illegal dose,
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Spet, ne gre za noro dozo, niti za ilegalno,
09:21
but very much at the high end of normal.
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a zelo na meji normalnega.
09:23
And so you're bound to make your new drug look better.
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Na ta način je bilo enostavno doseči, da vaše novo zdravilo izgleda boljše.
09:26
And so it's no surprise that overall,
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In nič presenetljivega ni, da v celoti
09:29
industry-funded trials
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testi, ki jih plača industrija,
09:31
are four times more likely to give a positive result
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štirikrat bolj verjetno dajo pozitivne rezultate
09:33
than independently sponsored trials.
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kot neodvisno opravljeni testi.
09:36
But -- and it's a big but --
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Ampak -- in gre za velik ampak --
09:39
(Laughter)
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(Smeh)
09:41
it turns out,
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izkaže se,
09:43
when you look at the methods used by industry-funded trials,
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da ko pogledate metode, ki jih za teste uporablja industrija,
09:46
that they're actually better
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so te pravzaprav boljše
09:48
than independently sponsored trials.
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od neodvisnih testov.
09:50
And yet, they always manage to to get the result that they want.
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In vseeno uspejo priti do željenih rezultatov.
09:53
So how does this work?
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Kako to deluje?
09:55
How can we explain this strange phenomenon?
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Kako lahko pojasnimo ta nenavaden pojav?
09:58
Well it turns out that what happens
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Izkaže se, da gre za to,
10:00
is the negative data goes missing in action;
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da se negativni rezultati izgubijo,
10:02
it's withheld from doctors and patients.
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da niso na voljo zdravnikom in pacientom.
10:04
And this is the most important aspect of the whole story.
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In to je najpomembnejši vidik zgodbe.
10:06
It's at the top of the pyramid of evidence.
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Je na vrhu piramide dokazov.
10:08
We need to have all of the data on a particular treatment
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Potrebujemo vse podatke o določenem zdravilu,
10:11
to know whether or not it really is effective.
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da bi vedeli, ali je dejansko učinkovito.
10:13
And there are two different ways that you can spot
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Obstajata dva načina za ugotavljanje,
10:15
whether some data has gone missing in action.
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ali se je določen del podatkov "izgubil".
10:17
You can use statistics, or you can use stories.
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Lahko uporabite statistiko ali pa zgodbe.
10:20
I personally prefer statistics, so that's what I'm going to do first.
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Osebno imam raje statistiko, zato bom začel z njo.
10:22
This is something called funnel plot.
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Tole je nekaj, čemur pravim zgodba v lijaku.
10:24
And a funnel plot is a very clever way of spotting
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Gre za pameten način odkrivanja,
10:26
if small negative trials have disappeared, have gone missing in action.
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ali so majhni negativni testi izginili, so pogrešani v akciji.
10:29
So this is a graph of all of the trials
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Tole je graf vseh testov,
10:31
that have been done on a particular treatment.
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ki so bili narejeni na določenem zdravilu.
10:33
And as you go up towards the top of the graph,
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In ko greste proti vrhu grafa,
10:35
what you see is each dot is a trial.
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vidite, da je vsaka točka posamezen test.
10:37
And as you go up, those are the bigger trials, so they've got less error in them.
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In ko greste navzgor, pridete do večjih testov in v njih je manj napak.
10:40
So they're less likely to be randomly false positives, randomly false negatives.
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Tako so manj verjetno naključno napačno pozitivni, naključno napačni negativni.
10:43
So they all cluster together.
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Vsi pridejo skupaj v grozd.
10:45
The big trials are closer to the true answer.
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Večji testi so bližje pravemu odgovoru.
10:47
Then as you go further down at the bottom,
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Ko potem greste navzdol,
10:49
what you can see is, over on this side, the spurious false negatives,
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lahko na tej strani vidite nepristne napačne negativne,
10:52
and over on this side, the spurious false positives.
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na tej strani pa nepristne napačne pozitivne.
10:54
If there is publication bias,
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Če obstaja pristranost pri objavi,
10:56
if small negative trials have gone missing in action,
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če so se majhni negativni testi "izgubili",
10:59
you can see it on one of these graphs.
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lahko to vidite na enem od teh grafov.
11:01
So you can see here that the small negative trials
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Tule lahko vidite, da so majhni negativni testi,
11:03
that should be on the bottom left have disappeared.
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ki bi morali biti levo spodaj, izginili.
11:05
This is a graph demonstrating the presence of publication bias
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Ta graf prikazuje prisotnost pristranske objave
11:08
in studies of publication bias.
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pri študijah o pristranski objavi.
11:10
And I think that's the funniest epidemiology joke
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In mislim, da je to najbolj smešna šala o epidemiologiji,
11:12
that you will ever hear.
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ki jo boste kdajkoli slišali.
11:14
That's how you can prove it statistically,
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Tako torej lahko to dokažete s statistiko,
11:16
but what about stories?
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kaj pa zgodbe?
11:18
Well they're heinous, they really are.
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Gnusne so, prav zares.
11:20
This is a drug called reboxetine.
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Tole je zdravilo reboksetin.
11:22
This is a drug that I myself have prescribed to patients.
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Sam sem ga predpisoval pacientom.
11:24
And I'm a very nerdy doctor.
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In sem zelo čudaški zdravnik.
11:26
I hope I try to go out of my way to try and read and understand all the literature.
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Upam, da se potrudim prebrati in razumeti vso literaturo.
11:29
I read the trials on this. They were all positive. They were all well-conducted.
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Prebral sem teste o tem. Vsi so bili pozitivni. Vsi so bili dobro opravljeni.
11:32
I found no flaw.
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Nisem našel napake.
11:34
Unfortunately, it turned out,
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Na žalost se je izkazalo,
11:36
that many of these trials were withheld.
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da so veliko teh testov zamolčali.
11:38
In fact, 76 percent
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V resnici so 76 odstotkov
11:40
of all of the trials that were done on this drug
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vseh testov na tem zdravilu
11:42
were withheld from doctors and patients.
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zamolčali pred zdravniki in pacienti.
11:44
Now if you think about it,
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Razmislite,
11:46
if I tossed a coin a hundred times,
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če stokrat vržete kovanec
11:48
and I'm allowed to withhold from you
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in vam za polovico metov
11:50
the answers half the times,
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lahko prikrijem rezultate,
11:52
then I can convince you
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potem vas lahko prepričam,
11:54
that I have a coin with two heads.
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da imam kovanec z dvema glavama.
11:56
If we remove half of the data,
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Če odstranimo polovico podatkov,
11:58
we can never know what the true effect size of these medicines is.
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ne moremo vedeti, kakšen je pravi učinek teh zdravil.
12:01
And this is not an isolated story.
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In to ni osamljen primer.
12:03
Around half of all of the trial data on antidepressants has been withheld,
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Okoli polovico testnih podatkov za antidepresive so zamolčali,
12:07
but it goes way beyond that.
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dogaja pa se še več.
12:09
The Nordic Cochrane Group were trying to get a hold of the data on that
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Nordic Cochrane Group je skušala dobiti podatke o tem
12:11
to bring it all together.
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in vse sestaviti v celoto.
12:13
The Cochrane Groups are an international nonprofit collaboration
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Cochrane Groups so mednarodna neprofitna zveza,
12:16
that produce systematic reviews of all of the data that has ever been shown.
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ki izvaja sistematski pregled vseh podatkov, ki so bili kdaj objavljeni.
12:19
And they need to have access to all of the trial data.
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In imeti morajo dostop do vseh testnih podatkov.
12:22
But the companies withheld that data from them,
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Vendar so podjetja prikrivala te podatke
12:25
and so did the European Medicines Agency
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in Evropska agencija za zdravila prav tako,
12:27
for three years.
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in to tri leta dolgo.
12:29
This is a problem that is currently lacking a solution.
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To je problem, za katerega trenutno ni rešitve.
12:32
And to show how big it goes, this is a drug called Tamiflu,
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Da vam pokažem, kako velik je, tole je zdravilo tamiflu,
12:35
which governments around the world
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za katerega so vlade po svetu
12:37
have spent billions and billions of dollars on.
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zapravile milijarde in milijarde dolarjev.
12:39
And they spend that money on the promise
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Ta denar so plačale zaradi obljube,
12:41
that this is a drug which will reduce the rate
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da bo to zdravilo zmanjšalo pojavnost
12:43
of complications with flu.
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zapletov pri gripi.
12:45
We already have the data
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Imamo že podatke,
12:47
showing that it reduces the duration of your flu by a few hours.
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ki kažejo, da zmanjša trajanje gripe za nekaj ur.
12:49
But I don't really care about that. Governments don't care about that.
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A to mene ne zanima. Vlade to ne zanima.
12:51
I'm very sorry if you have the flu, I know it's horrible,
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Zelo mi je žal, če imate gripo, vem da je grozna,
12:54
but we're not going to spend billions of dollars
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ampak ne bomo plačali milijard dolarjev za to,
12:56
trying to reduce the duration of your flu symptoms
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da bi vaše simptome gripe zmanjšali
12:58
by half a day.
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za pol dneva.
13:00
We prescribe these drugs, we stockpile them for emergencies
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Ta zdravila predpisujemo, hranimo jih za nujne primere,
13:02
on the understanding that they will reduce the number of complications,
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saj razumemo, da bodo zmanjšala raven zapletov,
13:04
which means pneumonia and which means death.
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kar pomeni pljučnico, kar pomeni smrt.
13:07
The infectious diseases Cochrane Group, which are based in Italy,
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Cochrane Group za infekcijske bolezni, ki ima sedež v Italiji,
13:10
has been trying to get
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se trudi od farmacevtskih podjetij dobiti
13:12
the full data in a usable form out of the drug companies
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popolne podatke v uporabni obliki,
13:15
so that they can make a full decision
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da bi lahko sprejeli odločitev,
13:18
about whether this drug is effective or not,
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ali je to zdravilo učinkovito ali ne,
13:20
and they've not been able to get that information.
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in doslej teh podatkov niso uspeli dobiti.
13:23
This is undoubtedly
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To je brez dvoma
13:25
the single biggest ethical problem
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največji etični problem
13:28
facing medicine today.
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današnje medicine.
13:30
We cannot make decisions
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Ne moremo sprejemati odločitev,
13:33
in the absence of all of the information.
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če nimamo celostnih informacij.
13:37
So it's a little bit difficult from there
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Od tu je malo težko
13:40
to spin in some kind of positive conclusion.
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priti do nekakšnega pozitivnega zaključka.
13:44
But I would say this:
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A rekel bi tole:
13:48
I think that sunlight
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mislim, da je sončna svetloba
13:51
is the best disinfectant.
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najboljše razkužilo.
13:53
All of these things are happening in plain sight,
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Vse te stvari se dogajajo vsem na očeh
13:56
and they're all protected
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in vse so zaščitene
13:58
by a force field of tediousness.
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s poljem počasnosti.
14:01
And I think, with all of the problems in science,
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Mislim, da je od vseh težav v znanosti
14:03
one of the best things that we can do
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ena najboljših stvari, kar jih lahko naredimo,
14:05
is to lift up the lid,
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ta, da dvignemo pokrov,
14:07
finger around in the mechanics and peer in.
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povrtamo po mehaniki in pogledamo vanjo.
14:09
Thank you very much.
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Hvala lepa.
14:11
(Applause)
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(Aplavz)
ABOUT THE SPEAKER
Ben Goldacre - DebunkerBen Goldacre unpicks dodgy scientific claims made by scaremongering journalists, dubious government reports, pharmaceutical corporations, PR companies and quacks.
Why you should listen
"It was the MMR story that finally made me crack," begins the Bad Science manifesto, referring to the sensationalized -- and now-refuted -- link between vaccines and autism. With that sentence Ben Goldacre fired the starting shot of a crusade waged from the pages of The Guardian from 2003 to 2011, on an addicitve Twitter feed, and in bestselling books, including Bad Science and his latest, Bad Pharma, which puts the $600 billion global pharmaceutical industry under the microscope. What he reveals is a fascinating, terrifying mess.
Goldacre was trained in medicine at Oxford and London, and works as an academic in epidemiology. Helped along by this inexhaustible supply of material, he also travels the speaking circuit, promoting skepticism and nerdish curiosity with fire, wit, fast delivery and a lovable kind of exasperation. (He might even convince you that real science, sober reporting and reason are going to win in the end.)
As he writes, "If you're a journalist who misrepresents science for the sake of a headline, a politician more interested in spin than evidence, or an advertiser who loves pictures of molecules in little white coats, then beware: your days are numbered."
Ben Goldacre | Speaker | TED.com