noun-modifying (irregular)
false positive; pseudo-positive
Medical term for a test result that appears positive but is not truly positive.
この検査では疑陽性が出ることがある。
This test can sometimes produce a false positive.
偽陽性 is a more common term for 'false positive' in medical contexts; 疑陽性 is less frequent but carries a nuance of 'suspected positive'.
Compound of 疑 (doubt, suspicion) or 擬 (pseudo, imitation) and 陽性 (positive). The exact historical derivation is uncertain; the spelling is conventionally associated with medical false positives.