TEDGlobal 2011
Ben Goldacre: Battling bad science
Ben Goldacre: U borbi protiv loše znanosti
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Svakog se dana susrećemo s vijestima o novim zdravstvenim savjetima, ali kako možemo znati jesu li ti savjeti dobri? Liječnik i epidemiolog Ben Goldacre pokazat će nam, ubrzano, načine na koje se dokazi mogu iskriviti, od posve očitih tvrdnji nutricionista do vrlo prepredenih smicalica farmaceutske 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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Liječnik sam, ali sam malo skrenuo s puta i zašao u polje istraživanja
00:18
and now I'm an epidemiologist.
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tako da sam sada epidemiolog.
00:20
And nobody really knows what epidemiology is.
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Nitko ne zna što je zapravo epidemiologija.
00:22
Epidemiology is the science of how we know in the real world
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Epidemiologija je znanost o tome kako znamo
00:25
if something is good for you or bad for you.
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je li nešto dobro ili loše za nas.
00:27
And it's best understood through example
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Primjerom je to najbolje objasniti
00:29
as the science of those crazy, wacky newspaper headlines.
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kao znanost iza onih ludih, šašavih novinskih natpisa.
00:34
And these are just some of the examples.
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Ovo su samo neki od primjera.
00:36
These are from the Daily Mail. Every country in the world has a newspaper like this.
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Ovo su novinski natpisi iz Daily Maila - svaka država na svijetu ima novine poput ovih.
00:39
It has this bizarre, ongoing philosophical project
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Imaju taj stalni bizarni filozofski projekt
00:42
of dividing all the inanimate objects in the world
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dijeljenja svih neživih stvari
00:44
into the ones that either cause or prevent cancer.
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na one koje ili uzrokuju ili sprečavaju rak.
00:47
So here are some of the things they said cause cancer recently:
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Neke od stvari za koje tvrde da uzrokuju rak jesu:
00:49
divorce, Wi-Fi, toiletries and coffee.
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razvod, Wi-Fi, toaletne potrepštine i kava.
00:51
Here are some of the things they say prevents cancer:
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Neke od stvari za koje kažu da sprečavaju rak:
00:53
crusts, red pepper, licorice and coffee.
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kora kruha, crvena paprika, slatkiši i kava.
00:55
So already you can see there are contradictions.
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Već primjećujete proturječnosti.
00:57
Coffee both causes and prevents cancer.
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Kava i uzrokuje i sprečava rak.
00:59
And as you start to read on, you can see
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Kad nastavite čitati dalje, počinjete shvaćati
01:01
that maybe there's some kind of political valence behind some of this.
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da iza ovakvih primjera stoji nekakva politička pozadina.
01:04
So for women, housework prevents breast cancer,
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Kućanski poslovi sprečavaju rak dojke kod žena,
01:06
but for men, shopping could make you impotent.
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dok shopping može dovesti do impotencije kod muškaraca.
01:09
So we know that we need to start
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Vidimo kako moramo početi
01:12
unpicking the science behind this.
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odvajati znanstvene činjenice od svega toga.
01:15
And what I hope to show
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Nadam se da ću pokazati
01:17
is that unpicking dodgy claims,
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kako odvajanje sumnjivih tvrdnji,
01:19
unpicking the evidence behind dodgy claims,
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odvajanje dokaza iza takvih tvrdnji,
01:21
isn't a kind of nasty carping activity;
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nije mukotrpna aktivnost,
01:24
it's socially useful,
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već je društveno korisno,
01:26
but it's also an extremely valuable
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ali i iznimno vrijedno
01:28
explanatory tool.
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kao sredstvo objašnjavanja.
01:30
Because real science is all about
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Bit prave znanosti jest
01:32
critically appraising the evidence for somebody else's position.
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kritičko procjenjivanje dokaza s drugog stajališta.
01:34
That's what happens in academic journals.
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Na taj način funkcioniraju znanstveni časopisi.
01:36
That's what happens at academic conferences.
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Tako funkcioniraju znanstvene konferencije.
01:38
The Q&A session after a post-op presents data
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Vrijeme pitanja i odgovora, nakon što su podaci izloženi,
01:40
is often a blood bath.
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postaje mjesto oštrih napada,
01:42
And nobody minds that. We actively welcome it.
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što nikome ne smeta. Aktivno se podržava.
01:44
It's like a consenting intellectual S&M activity.
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Nalikuje odobrenoj intelektualnoj sado mazo aktivnosti.
01:47
So what I'm going to show you
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Ono što ću vam pokazati
01:49
is all of the main things,
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jesu glavne stvari,
01:51
all of the main features of my discipline --
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glavne karakteristike moje discipline --
01:53
evidence-based medicine.
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medicine koja se temelji na dokazima.
01:55
And I will talk you through all of these
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Proći ću s vama kroz te karakteristike
01:57
and demonstrate how they work,
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i pokazati vam kako funkcioniraju,
01:59
exclusively using examples of people getting stuff wrong.
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koristeći isključivo primjere u kojima su ljudi nešto krivo shvatili.
02:02
So we'll start with the absolute weakest form of evidence known to man,
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Počet ćemo s najslabijim mogućim oblikom dokaza poznatim čovjeku:
02:05
and that is authority.
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autoritetom.
02:07
In science, we don't care how many letters you have after your name.
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Nas u znanosti ne zanima koliko titula imate uz ime.
02:10
In science, we want to know what your reasons are for believing something.
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Zanimaju nas razlozi zbog kojih vjerujete u nešto.
02:13
How do you know that something is good for us
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Kako znate je li nešto dobro
02:15
or bad for us?
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ili loše za nas?
02:17
But we're also unimpressed by authority,
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Autoritet nas ne impresionira
02:19
because it's so easy to contrive.
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jer ga je lako izmisliti.
02:21
This is somebody called Dr. Gillian McKeith Ph.D,
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Ovo je netko tko se zove Dr. Gillian McKeith, dr.sc.,
02:23
or, to give her full medical title, Gillian McKeith.
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ili punom liječničkom titulom - Gillian McKeith.
02:26
(Laughter)
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(Smijeh)
02:29
Again, every country has somebody like this.
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Svaka zemlja ima nekoga poput nje.
02:31
She is our TV diet guru.
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Ona je naš televizijski prehrambeni guru.
02:33
She has massive five series of prime-time television,
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Ima nevjerojatnih 5 sezona televizijskog serijala u udarnom terminu
02:36
giving out very lavish and exotic health advice.
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u kojem daje ekstravagantne i egzotične zdravstvene savjete.
02:39
She, it turns out, has a non-accredited correspondence course Ph.D.
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Ispostavilo se da ima doktorat s nepriznatog dopisnog tečaja
02:42
from somewhere in America.
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odnekud iz Amerike.
02:44
She also boasts that she's a certified professional member
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Hvali se, također, kako je i akreditirani stručni član
02:46
of the American Association of Nutritional Consultants,
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Američkog udruženja nutricionističkih savjetnika,
02:48
which sounds very glamorous and exciting.
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što zvuči nadasve glamurozno i uzbudljivo.
02:50
You get a certificate and everything.
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Od njih dobijete potvrdu i sve.
02:52
This one belongs to my dead cat Hetti. She was a horrible cat.
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Ova pripada mojoj mrtvoj mački Hetti. Bila je to grozna mačka.
02:54
You just go to the website, fill out the form,
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Samo otiđete na njihovu web stranicu, ispunite formular
02:56
give them $60, and it arrives in the post.
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i uplatite 60 dolara, a oni vam pošalju potvrdu poštom.
02:58
Now that's not the only reason that we think this person is an idiot.
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No, to nije jedini razlog zbog kojeg ovu osobu smatramo idiotom.
03:00
She also goes and says things like,
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Ona tvrdi stvari poput --
03:02
you should eat lots of dark green leaves,
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trebate jesti mnogo tamnozelenog lišća
03:04
because they contain lots of chlorophyll, and that will really oxygenate your blood.
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jer ono sadrži mnogo klorofila, što će dovesti mnogo kisika u vašu krv.
03:06
And anybody who's done school biology remembers
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Svatko tko je imao biologiju u školi sjetit će se
03:08
that chlorophyll and chloroplasts
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da klorofil i kloroplasti
03:10
only make oxygen in sunlight,
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stvaraju kisik samo na sunčevom svjetlu,
03:12
and it's quite dark in your bowels after you've eaten spinach.
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a u našim je crijevima posve mračno nakon što se pojeli špinat.
03:15
Next, we need proper science, proper evidence.
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Potrebna nam je prava znanost, sa stvarnim dokazima.
03:18
So, "Red wine can help prevent breast cancer."
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„Crno vino pomaže u sprečavanju raka dojke“.
03:20
This is a headline from the Daily Telegraph in the U.K.
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Ovo je naslov članka iz britanskog Daily Telegrapha.
03:22
"A glass of red wine a day could help prevent breast cancer."
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„Čaša crnog vina dnevno može pomoći u sprečavanju raka dojke“.
03:25
So you go and find this paper, and what you find
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Otiđete i nađete taj članak, i otkrit ćete
03:27
is it is a real piece of science.
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kako se radi o pravom znanstvenom radu.
03:29
It is a description of the changes in one enzyme
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Radi se o opisu promjena kod jednog enzima
03:32
when you drip a chemical extracted from some red grape skin
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kad nakapate kemijski ekstrakt iz kože crnog grožđa
03:35
onto some cancer cells
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na stanice raka,
03:37
in a dish on a bench in a laboratory somewhere.
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koje se nalaze u nekoj petrijevoj posudi na nekom stolu u nekom laboratoriju.
03:40
And that's a really useful thing to describe
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Ovo je stvarno korisno opisana stvar
03:42
in a scientific paper,
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u znanstvenom časopisu,
03:44
but on the question of your own personal risk
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ali po pitanju osobnog rizika
03:46
of getting breast cancer if you drink red wine,
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i dobivanju raka dojke, ukoliko pijete crno vino,
03:48
it tells you absolutely bugger all.
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kaže vam frišku figu.
03:50
Actually, it turns out that your risk of breast cancer
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Zapravo, čini se da se rizik od raka dojke
03:52
actually increases slightly
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neznatno povećava
03:54
with every amount of alcohol that you drink.
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pri svakoj količini popijenog alkohola..
03:56
So what we want is studies in real human people.
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Ono što zahtijevamo jesu studije na stvarnim ljudima.
04:00
And here's another example.
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Evo još jednog primjera.
04:02
This is from Britain's leading diet and nutritionist in the Daily Mirror,
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Ovaj dolazi od glavnog britanskog prehrambenog i nutricionističkog savjetnika u Daily Mirroru,
04:05
which is our second biggest selling newspaper.
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drugim najprodavanijim britanskim novinama.
04:07
"An Australian study in 2001
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„Istraživanje provedeno u Australiji 2001. godine
04:09
found that olive oil in combination with fruits, vegetables and pulses
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otkriva kako maslinovo ulje u kombinaciji s voćem, povrćem i mahunarkama
04:11
offers measurable protection against skin wrinklings."
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vidljvo štiti kožu od bora“.
04:13
And then they give you advice:
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Zatim slijedi savjet:
04:15
"If you eat olive oil and vegetables, you'll have fewer skin wrinkles."
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„Ako jedete maslinovo ulje i povrće, imat ćete manje bora“.
04:17
And they very helpfully tell you how to go and find the paper.
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Još vam vrlo susretljivo kažu kako doći do tog istraživanja.
04:19
So you go and find the paper, and what you find is an observational study.
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Kad pronađete to istraživanje, vidjet ćete kako se radi o opservacijskom istraživanju.
04:22
Obviously nobody has been able
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Očito je da se nitko nije vratio
04:24
to go back to 1930,
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u 1930. godinu,
04:26
get all the people born in one maternity unit,
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sakupio sve ljude rođene u jednom rodilištu,
04:29
and half of them eat lots of fruit and veg and olive oil,
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polovici dao da jede puno voća i povrća i maslinovog ulja,
04:31
and then half of them eat McDonald's,
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a drugoj polovici hranu iz McDonald'sa,
04:33
and then we see how many wrinkles you've got later.
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a zatim kasnije ustanovio koliko bora imaju.
04:35
You have to take a snapshot of how people are now.
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Ono što morate napraviti jest uzeti ljude u sadašnjem trenutku.
04:37
And what you find is, of course,
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I otkrit ćete, naravno,
04:39
people who eat veg and olive oil have fewer skin wrinkles.
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kako ljudi koji jedu povrće i maslinovo ulje imaju manje bora.
04:42
But that's because people who eat fruit and veg and olive oil,
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No, to je zato što su ljudi koji jedu voće i povrće i maslinovo ulje
04:45
they're freaks, they're not normal, they're like you;
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čudaci, oni nisu normalni, oni su poput vas;
04:48
they come to events like this.
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dolaze na događaje poput ovog.
04:50
They are posh, they're wealthy, they're less likely to have outdoor jobs,
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Radi se o dotjeranim i bogatim ljudima, s manje mogućnosti da rade posao na otvorenom,
04:53
they're less likely to do manual labor,
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ili fizički posao,
04:55
they have better social support, they're less likely to smoke --
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imaju bolju društvenu podršku, manje su mogućnosti da puše --
04:57
so for a whole host of fascinating, interlocking
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već se sada radi o nizu fascinantnih, međusobno povezanih
04:59
social, political and cultural reasons,
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društvenih, političkih i kulturalnih razloga
05:01
they are less likely to have skin wrinkles.
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zbog kojih su manje vjerojatnosti da imaju bore.
05:03
That doesn't mean that it's the vegetables or the olive oil.
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Ne radi se, dakle, samo o povrću i maslinovom ulju.
05:05
(Laughter)
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(Smijeh)
05:07
So ideally what you want to do is a trial.
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Idealno, ono što želite napraviti jest ispitivanje.
05:10
And everybody thinks they're very familiar with the idea of a trial.
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Svi misle da su dobro upoznati s pojmom ispitivanje.
05:12
Trials are very old. The first trial was in the Bible -- Daniel 1:12.
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Ispitivanja su vrlo stara. Prvo se dogodilo u Bibliji – Danijel 1:12.
05:15
It's very straightforward -- you take a bunch of people, you split them in half,
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Vrlo je jednostavno -- uzmete hrpu ljudi, podijelite ih u dvije jednake grupe,
05:17
you treat one group one way, you treat the other group the other way,
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jednu grupu tretirate na jedan način, drugu na drugi način,
05:19
and a little while later, you follow them up
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vratite im se nešto kasnije
05:21
and see what happened to each of them.
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i vidite što se dogodilo sa svakom od njih.
05:23
So I'm going to tell you about one trial,
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Ispričat ću vam o jednom ispitivanju
05:25
which is probably the most well-reported trial
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koje je u posljednjem desteljeću vjerojatno medijski najpraćenije
05:27
in the U.K. news media over the past decade.
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u Britaniji.
05:29
And this is the trial of fish oil pills.
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Radi se o ispitivanju kapsula ribljeg ulja.
05:31
And the claim was fish oil pills improve school performance and behavior
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Tvrdilo se da kapsule ribljeg ulja poboljšavaju rezultate u školi i ponašanje
05:33
in mainstream children.
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prosječne djece.
05:35
And they said, "We've done a trial.
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Rekli su, „Napravili smo ispitivanje.
05:37
All the previous trials were positive, and we know this one's gonna be too."
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Sva su prijašnja ispitivanja bila pozitivna, tako da znamo da će i ovo biti takvo“.
05:39
That should always ring alarm bells.
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Takva bi izjava odmah trebala biti znak za uzbunu.
05:41
Because if you already know the answer to your trial, you shouldn't be doing one.
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Ako već znate ishod svog ispitivanja, onda ga ne biste trebali raditi.
05:44
Either you've rigged it by design,
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Ili ste ga unaprijed namjestili
05:46
or you've got enough data so there's no need to randomize people anymore.
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ili imate dovoljno podataka pa nema potrebe za istraživanjem prema slučajnom odabiru.
05:49
So this is what they were going to do in their trial.
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Ispitivanje je bilo ovako organizirano.
05:52
They were taking 3,000 children,
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Uzeli su 3 000 djece
05:54
they were going to give them all these huge fish oil pills,
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i svima su davali velike kapsule ribljeg ulja,
05:56
six of them a day,
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šest na dan,
05:58
and then a year later, they were going to measure their school exam performance
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a zatim su, godinu dana kasnije, izmjerili njihove razultate na školskom ispitu
06:01
and compare their school exam performance
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i usporedili ih
06:03
against what they predicted their exam performance would have been
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s onime što su pretpostavili da bi bili rezultati
06:05
if they hadn't had the pills.
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da ta djeca nisu uzimala kapsule.
06:08
Now can anybody spot a flaw in this design?
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Primjećuje li netko rupu u tom ispitivanju?
06:11
And no professors of clinical trial methodology
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Profesori metodologije kliničkog ispitivanja
06:14
are allowed to answer this question.
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ne smiju odgovoriti na ovo pitanje.
06:16
So there's no control; there's no control group.
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Nema kontrolne skupine; kontrolna skupina ne postoji.
06:18
But that sounds really techie.
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Ali to zvuči previše stručno.
06:20
That's a technical term.
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To je stručnan termin.
06:22
The kids got the pills, and then their performance improved.
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Djeca su dobila kapsule i njihov se rezultat poboljšao.
06:24
What else could it possibly be if it wasn't the pills?
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Što bi drugo uopće moglo biti objašnjenje ako nisu pilule?
06:27
They got older. We all develop over time.
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Odrasla su. Svi se s vremenom razvijamo.
06:30
And of course, also there's the placebo effect.
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Naravno, postoji i placebo efekt.
06:32
The placebo effect is one of the most fascinating things in the whole of medicine.
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Placebo efekt jedna je od najfascinantnijih stvari u cijeloj medicini.
06:34
It's not just about taking a pill, and your performance and your pain getting better.
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Ne radi se samo o uzimanju tablete, vašem poboljšanju i smanjenju boli.
06:37
It's about our beliefs and expectations.
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Radi se o našim vjerovanjima i očekivanjima.
06:39
It's about the cultural meaning of a treatment.
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Radi se o kulturalnom značenju liječenja.
06:41
And this has been demonstrated in a whole raft of fascinating studies
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Ovo je dokazano na cijelom nizu fascinantnih istraživanja
06:44
comparing one kind of placebo against another.
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u kojima se jedna vrsta placebo efekta upoređivala s drugom.
06:47
So we know, for example, that two sugar pills a day
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Znamo, primjerice, da su dvije šećerne tablete na dan
06:49
are a more effective treatment for getting rid of gastric ulcers
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učinkovitije u liječenju želučanih čireva
06:51
than one sugar pill.
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od jedne šećerne tablete.
06:53
Two sugar pills a day beats one sugar pill a day.
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Dvije su šećerne tablete bolje od jedne.
06:55
And that's an outrageous and ridiculous finding, but it's true.
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Ovo je nečuveno i apsurdno otkriće, ali je istinito.
06:58
We know from three different studies on three different types of pain
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Iz triju različitih istraživanja o tri različite vrste boli znamo
07:00
that a saltwater injection is a more effective treatment for pain
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da je injekcija slane vode učinkovitiji način liječenja boli
07:03
than taking a sugar pill, taking a dummy pill that has no medicine in it --
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od uzimanja šećerne tablete, uzimanja placebo tablete --
07:07
not because the injection or the pills do anything physically to the body,
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ne zbog nekog fizičkog učinka injekcije ili tablete na tijelo,
07:10
but because an injection feels like a much more dramatic intervention.
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već zbog toga što injekcija predstavlja dramatičniju intervenciju.
07:13
So we know that our beliefs and expectations
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Znamo da se našim vjerovanjima i očekivanjima
07:15
can be manipulated,
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može manipulirati
07:17
which is why we do trials
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zbog čega se i provode istraživanja
07:19
where we control against a placebo --
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u kojima se ispituje placebo efekt --
07:21
where one half of the people get the real treatment
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u kojima polovica ljudi dobiva pravi lijek,
07:23
and the other half get placebo.
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a druga polovica placebo.
07:25
But that's not enough.
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No to nije dovoljno.
07:28
What I've just shown you are examples of the very simple and straightforward ways
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Pokazao sam vam primjere jednostavnih i laganih načina
07:31
that journalists and food supplement pill peddlers
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na koje novinari, trgovci dodacima prehrani
07:33
and naturopaths
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i naturopati
07:35
can distort evidence for their own purposes.
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iskrivljuju dokaze sebi u korist.
07:38
What I find really fascinating
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Ono što mene fascinira
07:40
is that the pharmaceutical industry
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jest da farmaceutska industrija
07:42
uses exactly the same kinds of tricks and devices,
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koristi iste smicalice i načine,
07:44
but slightly more sophisticated versions of them,
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ali malo sofisticiranije oblike istih,
07:47
in order to distort the evidence that they give to doctors and patients,
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kako bi iskrivila dokaze koje podnosi doktorima i pacijentima,
07:50
and which we use to make vitally important decisions.
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a koje koristimo kako bismo donijeli vrlo važne odluke.
07:53
So firstly, trials against placebo:
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Prvo, ispitivanja protiv placebo efekta:
07:55
everybody thinks they know that a trial should be
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svi misle kako bi se istraživanje trebalo temeljiti
07:57
a comparison of your new drug against placebo.
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na usporedbi novog lijeka i placeba.
07:59
But actually in a lot of situations that's wrong.
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U mnogim je slučajevima takav pristup pogrešan.
08:01
Because often we already have a very good treatment that is currently available,
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Često već imamo vrlo dobar lijek koji je trenutno dostupan,
08:04
so we don't want to know that your alternative new treatment
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pa ne želimo znati kako je vaš nov alternativan lijek
08:06
is better than nothing.
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bolje od ničega.
08:08
We want to know that it's better than the best currently available treatment that we have.
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Želimo znati da je bolji od trenutno najboljeg dostupnog lijeka.
08:11
And yet, repeatedly, you consistently see people doing trials
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Ali neprestano vidimo kako ljudi rade ispitivanja
08:14
still against placebo.
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uspoređujući ih s placebom.
08:16
And you can get license to bring your drug to market
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I možete dobiti dozvolu za plasiranje lijeka na tržište
08:18
with only data showing that it's better than nothing,
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samo na temelju podataka koji pokazuju da je vaš lijek bolji od ničega,
08:20
which is useless for a doctor like me trying to make a decision.
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što je meni kao liječniku beskorisno kad pokušavam donijeti odluku.
08:23
But that's not the only way you can rig your data.
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Nije ovo jedini način kako namjestiti podatke.
08:25
You can also rig your data
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Podatke možete namjestiti
08:27
by making the thing you compare your new drug against
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tako da ono s čime uspoređujete svoj novi lijek
08:29
really rubbish.
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izgleda kao sranje.
08:31
You can give the competing drug in too low a dose,
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Konkurentni lijek možete davati u premalenim količinama,
08:33
so that people aren't properly treated.
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pa ljudi ne dobivaju prikladno liječenje.
08:35
You can give the competing drug in too high a dose,
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Ili ga možete davati u prevelikim količinama,
08:37
so that people get side effects.
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tako da uzrokuje nuspojave.
08:39
And this is exactly what happened
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Upravo se to dogodilo
08:41
which antipsychotic medication for schizophrenia.
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s antipsihoticima za shizofreniju.
08:43
20 years ago, a new generation of antipsychotic drugs were brought in
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Prije 20 godina tržištu je predstavljena nova generacija antipsihotika
08:46
and the promise was that they would have fewer side effects.
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s obećanjem da uzrokuju manje nuspojava.
08:49
So people set about doing trials of these new drugs
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Počela su se raditi ispitivanja, usporedbe novih lijekova
08:51
against the old drugs,
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i starih,
08:53
but they gave the old drugs in ridiculously high doses --
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ali stari su lijekovi bili davani u nevjerojatno visokim dozama --
08:55
20 milligrams a day of haloperidol.
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20 miligrama haloperidola dnevno.
08:57
And it's a foregone conclusion,
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Unaprijed je određeno
08:59
if you give a drug at that high a dose,
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da ako ljudima dajete lijek u tako visokim dozama
09:01
that it will have more side effects and that your new drug will look better.
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imat će više nuspojava, a vaš će novi lijek izgledati bolje.
09:04
10 years ago, history repeated itself, interestingly,
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Prije 10 godina, povijest se ponovila
09:06
when risperidone, which was the first of the new-generation antipscyhotic drugs,
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sa, začuđujuće, risperidonom, prvim lijekom nove generacije antipsihotika
09:09
came off copyright, so anybody could make copies.
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čije je autorsko pravo isteklo pa se mogao kopirati.
09:12
Everybody wanted to show that their drug was better than risperidone,
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Svi su htjeli pokazati kako je njihov lijek bolji od risperidona
09:14
so you see a bunch of trials comparing new antipsychotic drugs
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pa ste mogli pronaći hrpu istraživanja u kojima su se novi antipsihotici
09:17
against risperidone at eight milligrams a day.
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uspoređivali sa risperidonom u dozi od osam miligrama dnevno.
09:19
Again, not an insane dose, not an illegal dose,
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Ne radi se tu o nekoj ludoj ili ilegalnoj dozi,
09:21
but very much at the high end of normal.
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ali o dozi koja je na gornjoj granici normalne.
09:23
And so you're bound to make your new drug look better.
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Tako da će vaš lijek zasigurno izgledati bolje.
09:26
And so it's no surprise that overall,
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Nije začuđujuće, gledano sveukupno,
09:29
industry-funded trials
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da će istraživanja financirana od strane farmaceutske industrije
09:31
are four times more likely to give a positive result
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četiri puta vjerojatnije dati pozitivan rezultat
09:33
than independently sponsored trials.
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nego nezavisno financirana istraživanja.
09:36
But -- and it's a big but --
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Ali -- i to je veliko ali --
09:39
(Laughter)
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(Smijeh)
09:41
it turns out,
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ispada da
09:43
when you look at the methods used by industry-funded trials,
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kad usporedite metode korištene u istraživanjima farmaceutskih industrija,
09:46
that they're actually better
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da su ta istraživanja zapravo bolja
09:48
than independently sponsored trials.
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od nezavisno financiranih ispitivanja.
09:50
And yet, they always manage to to get the result that they want.
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Ali svejedno uspiju dobiti rezultat koji žele.
09:53
So how does this work?
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Kako to funkcionira?
09:55
How can we explain this strange phenomenon?
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Kako možemo objasniti ovaj čudan fenomen?
09:58
Well it turns out that what happens
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Ispada da se to događa
10:00
is the negative data goes missing in action;
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zbog toga što negativni podaci nestanu;
10:02
it's withheld from doctors and patients.
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podaci se uskrate doktorima i pacijentima.
10:04
And this is the most important aspect of the whole story.
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Ovo je najvažniji dio cijele priče.
10:06
It's at the top of the pyramid of evidence.
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Nalazi se na vrhu piramide dokaza.
10:08
We need to have all of the data on a particular treatment
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Potrebni su nam svi podaci o određenom lijeku
10:11
to know whether or not it really is effective.
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kako bismo znali je li učinkovit ili nije.
10:13
And there are two different ways that you can spot
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Postoje dva različita načina na koje možete primijetiti
10:15
whether some data has gone missing in action.
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jesu li neki podaci nestali.
10:17
You can use statistics, or you can use stories.
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Možete koristiti statistiku ili priče.
10:20
I personally prefer statistics, so that's what I'm going to do first.
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Osobno, više volim statistiku, pa ću se prvo pozabaviti njome.
10:22
This is something called funnel plot.
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Postoji nešto što se zove ljevkasti grafikon.
10:24
And a funnel plot is a very clever way of spotting
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On predstavlja pametan načim zamjećivanja
10:26
if small negative trials have disappeared, have gone missing in action.
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jesu li maleni negativni pokusi nestali, je li ih pojela noć.
10:29
So this is a graph of all of the trials
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Ovo je grafikon svih ispitivanja
10:31
that have been done on a particular treatment.
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učinjenih za određeni lijek.
10:33
And as you go up towards the top of the graph,
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Kako se primičete vrhu grafikona
10:35
what you see is each dot is a trial.
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vidite da svaka točka predstavlja jedno ispitivanje.
10:37
And as you go up, those are the bigger trials, so they've got less error in them.
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Kako idete prema vrhu, ispitivanja su sve veća pa imaju manje pogrešaka.
10:40
So they're less likely to be randomly false positives, randomly false negatives.
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Manja je vjerojatnost da će biti nasumični lažni pozitivi ili lažni negativi.
10:43
So they all cluster together.
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Svi su zajedno skupljeni.
10:45
The big trials are closer to the true answer.
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Veća su ispitivanja bliža točnom odgovoru.
10:47
Then as you go further down at the bottom,
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Kako se spuštate prema dnu grafikona,
10:49
what you can see is, over on this side, the spurious false negatives,
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ono što vidite na ovoj strani jesu patvoreni lažni negativi,
10:52
and over on this side, the spurious false positives.
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a na ovoj strani patvoreni lažni pozitivi.
10:54
If there is publication bias,
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Ako postoje sustavne greške objavljivanja,
10:56
if small negative trials have gone missing in action,
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ako su mali negativni pokusi nestali,
10:59
you can see it on one of these graphs.
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možete to primijetiti na jednom od ovih grafikona.
11:01
So you can see here that the small negative trials
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Ovdje vidite kako su mali negativni pokusi,
11:03
that should be on the bottom left have disappeared.
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koji su se trebali nalaziti dolje lijevo, nestali.
11:05
This is a graph demonstrating the presence of publication bias
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Ovo je grafikon koji pokazuje prisutnost sustavne pogreške objavljivanja
11:08
in studies of publication bias.
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u istraživanjima sustavnih progrešaka objavljivanja.
11:10
And I think that's the funniest epidemiology joke
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Mislim da je ovo najsmješniji epidemiološki vic
11:12
that you will ever hear.
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koji ćete ikad čuti.
11:14
That's how you can prove it statistically,
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Ovako to dokazujete statistički,
11:16
but what about stories?
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ali što je s pričama?
11:18
Well they're heinous, they really are.
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One su gnusne, stvarno jesu.
11:20
This is a drug called reboxetine.
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Ovo je lijek reboksetin.
11:22
This is a drug that I myself have prescribed to patients.
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Ovaj sam lijek osobno prepisivao pacijentima.
11:24
And I'm a very nerdy doctor.
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Ja sam stvarno štreberski liječnik.
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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Svim se silama trudim pročitati i razumjeti svu literaturu.
11:29
I read the trials on this. They were all positive. They were all well-conducted.
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Čitao sam ispitivanja o ovom lijeku. Sva su bila pozitivna. Sva su bila dobro provedena.
11:32
I found no flaw.
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Nisam našao zamjerku.
11:34
Unfortunately, it turned out,
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Nažalost, na kraju se ispostavilo
11:36
that many of these trials were withheld.
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da su mnoga ispitivanja bila zatajena.
11:38
In fact, 76 percent
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Točnije, 76 posto
11:40
of all of the trials that were done on this drug
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svih ispitivanja napravljenih na ovom lijeku
11:42
were withheld from doctors and patients.
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bilo je zatajeno liječnicima i pacijentima.
11:44
Now if you think about it,
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Kad razmislite o tome,
11:46
if I tossed a coin a hundred times,
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ako bacim novčić stotinu puta
11:48
and I'm allowed to withhold from you
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i dozvoljeno mi je zatajiiti vam
11:50
the answers half the times,
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rezultate polovice tih bacanja,
11:52
then I can convince you
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mogu vas uvjeriti
11:54
that I have a coin with two heads.
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da imam novčić s dvije glave.
11:56
If we remove half of the data,
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Ako polovicu podataka uklonimo
11:58
we can never know what the true effect size of these medicines is.
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nikad ne možemo znati kakav točno učinak ima ovaj lijek.
12:01
And this is not an isolated story.
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Ovo nije jedina takva priča.
12:03
Around half of all of the trial data on antidepressants has been withheld,
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Zatajeno je oko polovice svih rezultata ispitivanja o antidepresivima.
12:07
but it goes way beyond that.
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ali tu priča ne staje.
12:09
The Nordic Cochrane Group were trying to get a hold of the data on that
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Grupa Nordic Cochrane pokušala je prikupiti podatke o tome,
12:11
to bring it all together.
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u želji da ih ujedini.
12:13
The Cochrane Groups are an international nonprofit collaboration
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Grupa Cochrane internacionalna je neprofitna udruga
12:16
that produce systematic reviews of all of the data that has ever been shown.
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koja objavljuje sustavne preglede svih podataka ikada prikazanih.
12:19
And they need to have access to all of the trial data.
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Potreban im je pristup svim podacima ispitivanja.
12:22
But the companies withheld that data from them,
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No, tvrtke im uskraćuju podatke,
12:25
and so did the European Medicines Agency
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kao i Europska agencija za lijekove,
12:27
for three years.
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i to zadnje tri godine.
12:29
This is a problem that is currently lacking a solution.
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Problem je to kojem trenutno nedostaje rješenje.
12:32
And to show how big it goes, this is a drug called Tamiflu,
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Da vam pokažem koliko daleko to ide: ovo je lijek Tamiflu,
12:35
which governments around the world
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na koji su vlade diljem svijeta
12:37
have spent billions and billions of dollars on.
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potrošile milijarde i milijarde dolara.
12:39
And they spend that money on the promise
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Potrošile su taj novac jer su se povodile za obećanjem
12:41
that this is a drug which will reduce the rate
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kako će ovaj lijek smanjiti stopu komplikacija
12:43
of complications with flu.
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vezanih uz gripu.
12:45
We already have the data
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Već imamo podatke
12:47
showing that it reduces the duration of your flu by a few hours.
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koji pokazuju da smanjuje trajanje gripe za par sati.
12:49
But I don't really care about that. Governments don't care about that.
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No, 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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Žao mi je ako imate gripu, znam da je to grozno,
12:54
but we're not going to spend billions of dollars
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ali ne ćemo potrošiti milijarde dolara
12:56
trying to reduce the duration of your flu symptoms
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kako bismo smanjili trajanje simptoma vaše gripe
12:58
by half a day.
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za pola dana.
13:00
We prescribe these drugs, we stockpile them for emergencies
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Prepisujemo ovakve lijekove, gomilamo rezerve za hitne slučajeve
13:02
on the understanding that they will reduce the number of complications,
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pod uvjetom da će smanjiti broj komplikacija,
13:04
which means pneumonia and which means death.
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što znači sprečavanje upale pluća i smrti.
13:07
The infectious diseases Cochrane Group, which are based in Italy,
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Grupa Cochrane koja se bavi zaraznim bolestima, sa sjedištem u Italiji,
13:10
has been trying to get
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pokušava dobiti
13:12
the full data in a usable form out of the drug companies
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sve podatke od farmaceutskih tvrtki, u razumljivom obliku,
13:15
so that they can make a full decision
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kako bi mogla donijeti odluku
13:18
about whether this drug is effective or not,
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je li taj lijek djelotvoran ili nije.
13:20
and they've not been able to get that information.
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Do sada nisu uspjeli dobiti te informacije.
13:23
This is undoubtedly
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Ovo je, bez sumnje,
13:25
the single biggest ethical problem
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najveći etički problem
13:28
facing medicine today.
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s kojim se suočava današnja medicina.
13:30
We cannot make decisions
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Ne možemo donositi odluke
13:33
in the absence of all of the information.
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ako nemamo sve informacije.
13:37
So it's a little bit difficult from there
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Teško je završiti
13:40
to spin in some kind of positive conclusion.
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nekim pozitivnim zaključkom.
13:44
But I would say this:
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Ali rekao bih ovo:
13:48
I think that sunlight
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mislim da je sunčeva svjetlost
13:51
is the best disinfectant.
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najbolji dezinficijens.
13:53
All of these things are happening in plain sight,
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Sve se ovo događa nama pred nosom,
13:56
and they're all protected
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a oni su svi zaštićeni
13:58
by a force field of tediousness.
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zaštitnim poljem sporosti.
14:01
And I think, with all of the problems in science,
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Smatram, sa svim problemima u znanosti,
14:03
one of the best things that we can do
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da najbolje što možemo napraviti
14:05
is to lift up the lid,
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jest podići pokolopac,
14:07
finger around in the mechanics and peer in.
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počeprkati po mehanici i zaviriti unutra.
14:09
Thank you very much.
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Hvala vam najljepša.
14:11
(Applause)
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(Pljesak)
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