Mediterranean

QUALITY CONTROL PROCEDURES

SPECIMEN ACCESSIONING AND ALIQUOTING

One blind QC sample is inserted into each screening batch by the accessioning personnel. Its content and location are unknown to the screening personnel. These blind samples are prepared in GCMS certified drug free urine. At least 20% of these are positive for amphetamine, BE, morphine, PCP, or THCA.

DRUGSCAN® employs an external blind program. This program involves the submission of ten samples monthly to challenge accessioning, screening and confirmation accuracy.

INITIAL TEST

Screening batches may contain up to 60 specimens which includes one blind QC. One set of open QC is analyzed before and after every 60 patient samples. This set includes one drug-free urine control (certified by GCMS), one control at 75% of the cutoff, and another at 125% of the cutoff. The drug-free control must screen negative, the 75% threshold control must screen negative but must be less negative than the drug free control, and the 125% threshold control must screen positive.  Blind samples are prepared in-house. Open controls are in a urine matrix and are acquired from a commercial source. If quality control criteria are not met, aliquots must be rescreened. Any aliquots in the batch which are not bracketed by acceptable quality control must be repeated.

CONFIRMATORY TEST

Batches are accumulated once screening is completed.  Each batch has a calibration curve and includes drug free QC, QC near the cutoff and one blind control (if re-flexed from screening).  Donor specimens are accepted if the QC of the batch meets the acceptable criteria. The other criteria that must be met includes acceptable chromatography, ion ratios +/- 20% of the calibrator, and the quantitation must be equal or greater than the HHS or other applicable mandated cutoff. In addition, the specimen must have met all criteria for a positive screen including a response greater than or equal to the cutoff calibrator and acceptable quality control. All chain of custody documents must be complete and intact before results may be reported.