Toxicological Analyses of Blood and Urine Samples in Pain Patients and Pre-surgical Control Patients to Investigate Incidences of Concealed and Feigned Substances

In this study medication compliance regarding current drug use is investigated using toxicological analyzes in two patient groups: patients from a pain management department and pre-surgical control patients. The aim is to explore the incidence of concealed and feigned substances and to determine the respective substance classes. Expecting that noncompliance is higher in the pain patient group, the investigators want to identify clinical risk factors for noncompliant drug report.