Application of different lupus anticoagulant diagnostic algorithms to the same assay data leads to interpretive discrepancies in some samples.

Background: Gold standard lupus anticoagulant (LA) assays and reference plasmas do not exist and detection is based on inference in a medley of coagulation assays, creating potential for interpretive discrepancies when applying different algorithms.

Objectives: To investigate discrepancies from applying different algorithms to a common data set.

Methods: Diagnostic data on 311 non-anticoagulated patients LA-positive by dilute Russell's viper venom time (dRVVT) and/or dilute activated partial thromboplastin time (dAPTT) assays were employed to compare algorithms.