What is a Good NNT/NNH number?

Prof. Mary Ferrill clarifies when to calculate a NNT/NNH number and what is a good NNT/NNH number in this video.

First, there are two major steps to determine when a NNT/NNH number should be calculated. Make sure you understand them and move on.

Besides, she also demonstrates the crossing and touching of confidence intervals (CIs) by four examples. The most important thing is that, remember to check the width of the CI no matter what you are looking at to ensure the reliability of the data.

What is a good NNT/NNH number? A good NNT is obviously small and a good NNH is large.If you don’t have any idea in the studies, you need to pull similar trials and see if NNT were listed there.

Finally, NNT for treatment is a much smaller number for prevention because you have to treat lots of patients to prevent something. If NNT is less than 300, it is good for prostate cancer prevention; if NNT is less than or equal to five, it is good for the treatment of migraines.