This one made me think
The meme is talking about a common probability error that surveys have shown even doctors are prone to making.
Why you’re probably ok:
The rarity of the disease far exceeds the error rate of the positive test. Meaning, the disease occurs in 1 out of a million people, so if you are tested at random and show positive, you only have a 1 out of 30,000 chance (the 3% false-positive rate) of being the the 1 person who truly has the disease.
I suppose it depends on how many people are tested, and whether the errors are false positives or false negatives. Is the test population gigantic, and 2.999% of people tested receive a false positive (meaning that only 0.001% of people tested are correctly diagnosed with the disease)? Or are only people who are suspected of having the disease tested, with 2.999% of people tested receiving a false negative?
As far as I can see, you can’t really fear or rejoice with the results until you know the false positive/negative ratio.
The Picard Maneuver
Bwaz