Averting Potential Misinterpretations and Diagnostic Misapplications of Misleading Laboratory Results

Diagnosis is a dynamic process, encompassing clinical presentation of pathophysiology, workup investigations and appropriate interpretations/integration of all data. Diagnostic accuracy is expected when based on multiple tests/investigations. However, when diagnosis is based on a single abnormal laboratory test, considered to be fundamental and deterministic, an early test's error could cascade and propagate, triggering unnecessary investigations, longer hospitalisation and possible diagnostic misapplications. Up to 70% of diagnoses involve laboratory tests. Immunologically based analyses (immunoassays) have two fundamental features: (a) inherently higher analytical error rate than other common routine tests such as U&E, LFT, bone profile, FBC, et cetera, and (b) universality, affecting measurements regardless of the analyte's nature or the immunoassay's provider. Averting potentially erroneous results necessitates a paradigm shift which can be made by (a) intuitive use of a statistical paradigm (Bayesian reasoning), which will be explained by a simple example and without equations, and (b) appropriate and more use of follow-up confirmatory tests when the test has consequences and potential diagnostic misapplications by using available tests in all hospital laboratories.