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Health news:
 
June 2010 - Dec 2013

Minimizing breast cancer risk

May 2010

Time to move beyond salt ?

Salt hypothesis vs. reality

Is sodium bad?

April 2010

Salt studies: the latest score

From Dahl to INTERSALT

Salt hypothesis' story

March 2010

Salt war

Do bone drugs work?

Diabetes vs. drugs, 3:0?

February 2010

The MMR vaccine war: Wakefield vs. ?

Wakefield proceedings: an exception?

Who's afraid of a littl' 1998 study?
 

January 2010

Antibiotic children

Physical activity benefits late-life health

Healthier life for New Year's resolution

 

December 2009

Autism epidemic worsening: CDC report

Rosuvastatin indication broadened

High-protein diet effects

 

November 2009

Folic acid cancer risk

Folic acid studies: message in a bottle?

Sweet, short life on a sugary diet

 

October 2009

Smoking health hazards: no dose-response

C. difficile warning

Asthma risk and waist size in women

 

September 2009

Antioxidants' melanoma risk: 4-fold or none?

Murky waters of vitamin D status

Is vitamin D deficiency hurting you?

 

August 2009

Pill-crushing children

New gut test for children and adults

Unhealthy habits - whistling past the graveyard?

 

July 2009

Asthma solution - between two opposites that don't attract

Light wave therapy - how does it actually work?

Hodgkin's lymphoma in children: better alternatives

 

June 2009

Hodgkin's, kids, and the abuse of power

Efficacy and safety of the conventional treatment for Hodgkin's:
behind the hype

Long-term mortality and morbidity after conventional treatments for pediatric Hodgkin's

 

May 2009

Late health effects of the toxicity of the conventional treatment for Hodgkin's

Daniel's true 5-year chances with the conventional treatment for Hodgkin's

Daniel Hauser Hodgkin's case: child protection or medical oppression?

April 2009

Protection from EMF: you're on your own

EMF pollution battle: same old...

EMF health threat and the politics of status quo
 

March 2009

Electromagnetic danger? No such thing, in our view...

EMF safety standards: are they safe?

Power-frequency field exposure
 

February 2009

Electricity and health

Electromagnetic spectrum: health connection

Is power pollution making you sick?

January 2009

Pneumococcal vaccine for adults useless?

DHA in brain development study - why not boys?

HRT shrinks brains

NEWS ARCHIVE
2009
2008
2007

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February 2007

Are health studies results misleading?

In his Time Magazine health article (February 2007), Michael D. Lemonik argues that the usual manner in which results of health studies are presented doesn't convey the whole truth. It may be even misleading.

The reason is that a figure - most often given in percentage points - of how much a certain factor (treatment, nutrient, medication, toxin, etc.) increases the chances of a certain outcome, doesn't say nothing about

what is the actual probability
of it happening to you in the first place.

To illustrate this, the author cites a 30% heart attack rate reduction with statin drugs - according to a study - as opposed to no treatment. It implies quite significant benefit, but what is needed to judge its actual importance is the basic risk level for heart attack.

The article states that it is so called "number needed to treat" (NNT) which reveals this vital piece of information. It tells how many patients, on average, need to be treated in order to average a single specific effect - in this case benefit - compared to the control group (no treatment, or some other treatment).

For statins, the NNT is, according to the article, about 50 for heart attack. This number tells you that, statistically, statin treatment will benefit one out of every 50 patients. In other words, if your condition is comparable to those of subjects in the study, it would statistically decrease your chances of suffering heart attack by 1/50, or 2%.

Now, there is a huge apparent difference between 30% (heart attack rate reduction) and 2% (your personal statistical risk reduction). While both numbers are correct, the latter is the one that gives you the actual picture. The numbers implicate that your chances of suffering heart attack are about 4.7% with statin treatment, and either 30% or 2% more - about 6.7% - depending on whether you take relative or nominal increase, without any treatment.

This results from a simple formula for the "number needed to treat",

NNT=100/(%CG-%EG),

with %CG being the percentage of a specific outcome in the control group (no treatment, placebo, or established therapy) and %EG being the percentage of that same outcome in the experimental group.

But the NNT value alone still hides the important aspect of

what is your risk of being affected in the first place.

It is merely an efficacy indicator for the statistical patient population. NNT would be the same (50) for any 2% nominal difference in the EG/CG efficacy, say, for 1% and 3%, or 50% and 52%. In the first case, the relatively low, but not negligible risk is reduced threefold - definitely worth attention - and in the second one the very high risk is only slightly - statistically negligible - reduced.

Seems that KISS ("keep it simple silly") approach is still the best. Why not to omit still potentially confusing NNT terminology, and

state it simply as it is:

for a given group of patients, statins reduced the chances of heart attack from 6.7% to 4.7%, or from 1 in 15 to 1 in 21. It shows clearly both, degree of benefit and treatment importance (measured by the chances of your health being negatively affected if not subjected to a treatment). Is that too plain and simple for those who conduct medical studies?

Here are the NNTs for some common ailments/treatments you may find interesting (source: Centre for evidence-based medicine).

SUBJECT

OUTCOME

 CR (%)

ER (%)

NNT

chronic fatigue

improved

 behavior therapy(26.7)

orthodox therapy(46.3)

2

 heart

 heart attack

placebo (3.9)

aspirin (3.4)

200

 heart

 heart attack

no exercise (75.5)

exercise (34)

2.4

 heart

 heart attack

placebo (34)

vitamin E (19)

6.7

migraine

frequency

placebo (54)

riboflavin (19)

3

asthma

bedtime attack

standard treatment (20)

clinic (7)

8

hip surgery

 DV thrombosis

placebo (1.5)

aspirin (1)

200

hip surgery

pulmonary embolism

placebo (1.2)

aspirin (0.7)

200

influenza

 sickness

placebo (10.2)

vaccine (1.4)

11.4

You've heard so many times doctors (and layman-like) recommending daily aspirin for heart protection. It has become part of the culture. But when you look at the numbers, statistically, it will help only one person in 200. On the other hand, vitamin E supplementation will help 1 person in 7, while exercise will help two out of every five persons.

Why is vitamin E, despite being

30 times more efficient heart protection than aspirin

so infamous? Probably the main reason is that nutrients in general, and their significance in preserving and regaining health are still being mainly ignored by today's "official", business-minded medicine.

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