How to Measure a Medical Treatment’s Potential for Harm

Sometimes, the chance of a medical treatment’s harm can be greater than the potential for benefit…

man walking drawing
Knowing a medical therapy’s potential for benefit is not enough., we must also consider potential harms.

Not every person who takes a medication will suffer a side effect, just as not every person will see a benefit. And sometimes, the chance of harm can be greater than the potential for benefit…

For instance, for about every 1,500 women assigned to get mammography screening for 10 years, one might be spared a death from breast cancer (though she’d most likely die of some other cause). But about five more women would undergo surgery and about four more would undergo radiation, both of which can have dangerous, even life-threatening, side effects…

Continue reading How to Measure a Medical Treatment’s Potential for Harm,
nytimes, FEB. 2, 2015.

Related post: Can This Treatment Help Me? There’s a Statistic for That,
nytimes, JAN. 26, 2015.

How to Measure a Medical Treatment’s Potential for Benefit

In truth, medical care is often far less effective than most believe

number-needed-to-treat image
People at risk for a first heart attack are often recommended to take aspirin daily to prevent it. Only a very few will actually see this benefit and there’s no way to know in advance who…

In truth, medical care is often far less effective than most believe. Just because you took some medicine for an illness and became well again, it doesn’t necessarily mean that the treatment provided the cure.

This fundamental lesson is conveyed by a metric known as the number needed to treat, or N.N.T. Developed in the 1980s, the number needed to treat tells us how many people must be treated for one person to derive benefit. An N.N.T. of one would mean every person treated improves and every person not treated fails to, which is how we tend to think most therapies work.

What may surprise you is that number needed to treat are often much higher than one. Double- and even triple-digit N.N.T.s are common. ”

Continue reading Can This Treatment Help Me? There’s a Statistic for That,
nytimes, JAN. 26, 2015.

Related post: How to Measure a Medical Treatment’s Potential for Harm,
nytimes, FEB. 2, 2015.