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Author Topic: What is the Numbers Needed To Treat - NNT - value in statistics?  (Read 6113 times)

Offline NobodySavedMe

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Next time you see adverts for a drug remember this very important number called NNT.


Numbers Needed To Treat.


NNT


Upon first glance, the ad boasts that Lipitor reduces heart attacks by 36 percent. But there is an asterisk. And when you follow the asterisk, you find the following in much smaller type:

"That means in a large clinical study, 3% of patients taking a sugar pill or placebo had a heart attack compared to 2% of patients taking Lipitor."

What this means is that for every 100 people who took the drug over 3.3 years, three people on placebos, and two people on Lipitor, had heart attacks. That means that taking Lipitor resulted in just one fewer heart attack per 100 people.


There's one medical statistic doctors don't much talk about despite its importance. It's called number needed to treat, or NNT. Itís a measure developed in the past 20 years, and itís one of the best-kept statistical secrets in medicine.

The idea of NNT is simple enough. Most clinical trials look at how much better people do on a particular medicine. NNT answers the question: How many people have to take a particular drug to avoid one incidence of a medical issue (such as a heart attack, or recurrence of cancer)? For example, if a drug had an NNT of 50 for heart attacks, then 50 people have to take the drug in order to prevent one heart attack.

That doesnít sound like a lot, so pharmaceutical companies tend to keep the number quiet and focus on broader, U.S. population-based statistics. But that could be changed if you ask for the NNT up front the next time you're handed a prescription.

Read more info here about how you are being tricked and hoodwinked:-

http://articles.mercola.com/sites/articles/archive/2008/05/08/medicine-s-dirty-little-secret.aspx?source=nl

<mod edit - changed the title to 'Numbers Needed to Treat' for clarity>
« Last Edit: 12/05/2008 22:53:08 by chris »


 

Offline Bored chemist

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NNT is hardly the world's best kept secret.
It would be nice if the pharmaceuticals companies were straightforward in reporting the value of their products in their advertising.
It would also be nice if the makers of breakfast cereals, cars, and everything else did the same. Neither group is going to, and for the same reasons. Caeveat emptor.

Here in the UK direct advertising of drugs to patients rather than doctors is limited. The idea is that the doctors are less likely to be fooled.
 

Offline NobodySavedMe

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NNT is hardly the world's best kept secret.
It would be nice if the pharmaceuticals companies were straightforward in reporting the value of their products in their advertising.
It would also be nice if the makers of breakfast cereals, cars, and everything else did the same. Neither group is going to, and for the same reasons. Caeveat emptor.

Here in the UK direct advertising of drugs to patients rather than doctors is limited. The idea is that the doctors are less likely to be fooled.

It is a very well kept secret as it is NEVER mentioned when they are plugging their drugs.The news people never mention it as they are either ignorant or it's beyond their intellectual understanding.

I can safely say the NNT has NEVER EVER been mentioned on tv or the mass media.

They always quote percentages which the drug company tells them to use.

I understand the reporters are given a buffet and a free beer at these "presentations" and the copy is written down for them which they copy/paste and is then hailed as a "$medical $breakthrough".

In any case they should be prosecuted for false advertising and gross falsification of claims in addition to prosecution for every injury and death caused by these "medications" which seem to have marginal benefit as the NNT numbers testify.

Your assertion about caveat emptor is absurd and dangerous and shows your association with big business and making excuses for their dangerous practices.

Does the chief executives and board members even remember you or care about you?

Perhaps you want to remove the warning labels on all products sold because of your caveat emptor.
« Last Edit: 14/05/2008 12:13:18 by NobodySavedMe »
 

Offline Bored chemist

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"I can safely say the NNT has NEVER EVER been mentioned on tv or the mass media."
Does the internet count as mass media?
"The news people never mention it as they are either ignorant or it's beyond their intellectual understanding."
 If it's beyond the journalists, how well do you think the public would understand it?
If they wouldn't understand it why waste broadcast time telling them about it?
 
"Your assertion about caveat emptor is absurd and dangerous and shows your association with big business and making excuses for their dangerous practices."
OK fine; if you want to ignore the fact that, like other big businesses, Pharma tends to keep quiet about the downside of their products that's great.
However for those of us who do realise that, I think that telling the buyer to beware is eminently sensible advice.
The alternative seems to be "Buyer, blindly buy stuff- none of it is ever a ripoff or dangerous".
I guess we have differning opinions as to what counts as absurd.

While you are at it, perhaps you would like to tell me what you think my association with big business is exactly? Or was that just an ad hom. atack, made in the hope that I wouldn't notice?

"Does the chief executives and board members even remember you or care about you?"
Of course not. That's why, as a buyer, I have to care about me.

"Perhaps you want to remove the warning labels on all products sold because of your caveat emptor."
No, that's obviously the opposite of what I want. How could the buyer take care about what they bought without information?
Why are you making such a silly sugestion?
 

Offline NobodySavedMe

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"I can safely say the NNT has NEVER EVER been mentioned on tv or the mass media."
Does the internet count as mass media?
"The news people never mention it as they are either ignorant or it's beyond their intellectual understanding."
 If it's beyond the journalists, how well do you think the public would understand it?
If they wouldn't understand it why waste broadcast time telling them about it?
 
"Your assertion about caveat emptor is absurd and dangerous and shows your association with big business and making excuses for their dangerous practices."
OK fine; if you want to ignore the fact that, like other big businesses, Pharma tends to keep quiet about the downside of their products that's great.
However for those of us who do realise that, I think that telling the buyer to beware is eminently sensible advice.
The alternative seems to be "Buyer, blindly buy stuff- none of it is ever a ripoff or dangerous".
I guess we have differning opinions as to what counts as absurd.

While you are at it, perhaps you would like to tell me what you think my association with big business is exactly? Or was that just an ad hom. atack, made in the hope that I wouldn't notice?

"Does the chief executives and board members even remember you or care about you?"
Of course not. That's why, as a buyer, I have to care about me.

"Perhaps you want to remove the warning labels on all products sold because of your caveat emptor."
No, that's obviously the opposite of what I want. How could the buyer take care about what they bought without information?
Why are you making such a silly sugestion?

You seem to be back peddling now.You said caveat emptor, not I.

Caveat emptor implies that the buyer beware of the product.

Joe public cannot be expected to be familiar with the complexities of assorted chemicals and their effects on humans.

Doctors are largely over paid pimps for drug companies and are corrupted and get a daily brain washing from drug companies representatives and easily influenced by a women in a push up bra and a short skirt.

When was the last time a doctor mentioned NNT to you?
 

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