Quality Control & Process Improvement Flashcards

Which statistical tool uses upper and lower control limits to monitor process variation over time?

Answer: Control chart (Shewhart chart)

Control charts display process data over time with control limits to distinguish common-cause from special-cause variation.

In forensic toxicology quality control, a 'matrix-matched' calibrator is used primarily to:

Answer: Compensate for matrix effects that alter analyte signal

Matrix-matched calibrators mimic the biological specimen matrix so that ion suppression or enhancement affects calibrators and samples equally.

A Six Sigma project team is determining defect rates. Which metric expresses defects per million opportunities (DPMO)?

Answer: Sigma level

Sigma level is directly derived from DPMO; 6 Sigma corresponds to 3.4 DPMO.

During a forensic autopsy laboratory audit, reviewers find that case files lack documentation of chain of custody for external specimens. This finding is BEST categorized as:

Answer: Major nonconformance

Missing chain-of-custody documentation is a major nonconformance because it directly compromises specimen integrity and legal defensibility.

Which lean principle focuses on producing only what is needed, when it is needed, in the amount needed?

Answer: Just-in-time (JIT)

Just-in-time production minimizes inventory and waste by synchronizing production with demand.

In a forensic laboratory, a second-source calibration standard is used primarily to verify:

Answer: Accuracy of the primary calibration standard

A second-source standard from a different supplier or lot confirms the primary calibration standard is correctly prepared and uncontaminated.

The PDCA cycle step in which root cause analysis and corrective actions are tested is:

Answer: Do

The 'Do' step involves implementing the planned changes or tests on a small scale to gather data.