Comparison of Immunoassay Results near Cutoff Values with LC-MS/MS in Individuals with Substance Use Disorder Under Probation

Ugur Fahri Yurekli, Ozlem Orer Beginoglu

Highlights What are the main findings? Agreement between immunoassay screening and LC–MS/MS confirmation varied markedly across analyte groups in urine samples with results near assay cutoff values.Immunoassays produced notable false-positive findings for amphetamines and opioids and false-negative findings for cannabinoids and opioids. What are the implications of the main findings? Immunoassay results close to c…