Evaluation of 8-years of data: Forensic and clinical comparison of opiate cut-off values in urine samples

Abstract

Objective: Opiates are one of the most abused drugs with growing concern.In recent years, it is seen that changes have been made to the cut-off values for opiates.The cut-offs for opiates in screening tests increased from 300 to 2000ng/mL.The aim of this study was to present the opiate results of 8-year study and to evaluate the data according to cut-off values increased from 300 to 2000ng/mL.

Methods: The preliminary diagnoses of the cases, outpatient admitted clinics, and results of the drug tests were compared according to the two cut-off values. A total of 11,348 urine samples were analyzed.Screening tests were performed using enzymatic immunoassay method Randox Evidence and CEDIA,and confirmatory analysis was conducted using Gas Chromatography-Mass Spectrometry(GC-MS) with standard protocol for quantification.

Results: According to the 300ng/mL cut-off value,3.45% (n=392) of the cases were opiate-positive. 69.1% of the cases(n=271) were from addiction polyclinics. In this study, it is shown that 39.8% of cases requiring judicial action were missed when the cut-off value was raised to 2000ng/mL, underlining the critical impact of cut-off values on legal outcomes.

Conclusion: The findings suggest that adjusting cut-off values according to specific clinical and forensic needs can improve the accuracy of drug testing and provide more reliable results for legal decisions.