I have the sensitivity
value known as, 91%. Can we derive the True Positive (TP) and True Negative (TN) values from that. Is that possible at all?
Thanks.
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Sign up to join this communityI have the sensitivity
value known as, 91%. Can we derive the True Positive (TP) and True Negative (TN) values from that. Is that possible at all?
Thanks.
If the only thing you know is the sensitivity, the answer is no. Even if you know the total population this sensitivity was calculated in, the answer is still no. Because the sensitivity calculation only contains information about the TP and FN. You still have the unaccounted false positives and true negatives. You need more information to be able to calculate these.
Someone should correct me if I'm wrong, but I'm pretty you also need the prevalence (so what percentage actually has the outcome) and total population to be able to calculate this. Then: FP = (1 - Specificity) * (1 - Prevalence); TN = Specificity * (1 - Prevalence); TP = Sensitivity * Prevalence; FN = (1 - Sensitivity) * Prevalence. These formulas give a fraction, which you'll then have to multiply with the total population to get the exact TP and TN values.
ans: it is not correct way of calculation, I tested with many original values, all are incorrect output.