Can someone explain this in English please

[Startingmyjourney]

Hi could someone explain what this means.... 70% sensitivity and 90% negative predictive value for advanced fibrosis

Is this a good thing or a bad thing? It's in relation to a fib 4 score

Thanks in advance you lovely lot!

[MINTVCX]

"90% negative predictive value for advanced fibrosis"

It means when you have low score it means you have 90% chance not to have advanced fibrosis. Generally fib-4 is better to rule out advanced fibrosis than to confirm it (when you have high value further tests are needed).

advanced fibrosis = F3-F4 so you can still have F1-F2 with low fib-4 score.

[Startingmyjourney in reply to MINTVCX]

Thank you. So that's a good result?

[MINTVCX in reply to Startingmyjourney]

If you get low Fib-4 basically yes but 90% is not 100%. Also Fib-4 has limited efficiency when we talk about some other liver diseases like for example AIH.

healthunlocked.com/fatty-li...

[Roy1955]

Good result.About as good as it gets

They never say 100%

[Serenity64]

70% sensitivity means that 70% of people with the condition (advanced fibrosis) will screen positive (so 30% who do actually have the condition will screen negative). It's a measure of how well the test works to identify people who do have advanced fibrosis.

90% negative predictive value means that 90% of people who screen negative for advanced fibrosis do not in fact have advanced fibrosis. That's a fairly high percentage, and it means that if someone screens negative, they most likely do not have advanced fibrosis. It's a measure of test accuracy.

[Darwin3]

Put another way, sensitivity and specificity in this context are applied to screening tests to determine the number of false negatives (people with a negative result, but actually have a condition) verses false positives (people with a positive test but do not have a condition).

A perfect screening test would always identify people with a condition (sensitivity = 100%) and never identify someone without a condition (specificity = 100%). This is never the case, but screening tests are just that, screening to identify people who probably do not have a condition, and so do not require further follow-up, as opposed to those who probably have a condition and require referral for further diagnostic tests.

FIB-4 is widely used in general practice since it is quick and easy to undertake, and relatively inexpensive. Before it became widely used, everyone had to attend a hospital liver clinic if fibrosis was suspected. Your doctor should have a set of criteria by which further referral for investigation is determined. These are usually locally developed pathways based upon nationally accepted guidelines. If you want further information on how this is all determined, then the most creditable source of information is on the NICE website.

I note that you did not quote your actual FIB-4 score, but hope this explanation helps to unravel some of the professional jargon that surrounds what can be confusing concepts to grasp.