When “phenotype variability” hides incompatible definitions

“Phenotype variability” can mean variation in observed findings, variation in syndrome labels, or variation in recruitment criteria. Those are not interchangeable for semantic case matching. For example, two interstitial cystitis trials might both recruit a “pain-predominant phenotype,” while one encodes pelvic pain as sufficient and the other requires bladder-filling pain; a patient’s apparent match then depends on a missing qualifier rather than a biological difference. Which phenotype definitions were compared, and were recruitment features represented as individual findings with qualifiers or only as cohort-level labels?