The Predictive Aplastic Score System (PASS) is a validated clinical tool that distinguishes acquired aplastic anemia (AA) from inherited bone marrow failure syndromes (IBMFS) in adults without immediate genetic testing.
PASS uses seven readily available clinical and laboratory variables, achieving excellent diagnostic accuracy, with an AUC of 0.990 in the training cohort and 0.977 in external validations.
The model provides 100% positive predictive value for AA at scores ≥30, enabling rapid clinical decision-making and potentially reducing reliance on time-consuming or inaccessible genetic tests.
PASS facilitates differentiation in approximately 80% of adult cases, improving early diagnosis and appropriate treatment selection.