You’re assuming a diagnostic test can be designed for 100% accuracy and this is not possible as disease states are spectrums not discrete categories.
“Normal ranges” in lab values are just confidence intervals of population means which by definition that some normal people will have abnormal values and some patients with a disease will have normal values.
The same is true for imaging. For example we use size criteria a lot. There is nothing different about 4.1 cm adrenal nodules and 3.9 cm nodules to explain why the former gets surgery and the latter gets called benign other than pre-test probability and acceptable false positive and false negative rates, whether this is measured by a human or AI.
“Normal ranges” in lab values are just confidence intervals of population means which by definition that some normal people will have abnormal values and some patients with a disease will have normal values.
The same is true for imaging. For example we use size criteria a lot. There is nothing different about 4.1 cm adrenal nodules and 3.9 cm nodules to explain why the former gets surgery and the latter gets called benign other than pre-test probability and acceptable false positive and false negative rates, whether this is measured by a human or AI.