Quality Control & Process Improvement Flashcards
7 cards from real CLC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Quality Control & Process Improvement flashcards as text
A laboratory notices its Levey-Jennings chart shows 8 consecutive QC results on the same side of the mean. Which Westgard rule is violated?
Answer: 10x rule
The 10x rule is violated when 10 consecutive QC values fall on the same side of the mean, indicating systematic bias; 8 in a row triggers the warning version of this rule.
Which statistical tool is BEST suited for identifying the root cause of a process defect in a laboratory quality improvement project?
Answer: Fishbone (Ishikawa) diagram
A fishbone diagram systematically explores all potential causes (equipment, methods, materials, personnel, environment) contributing to a defect.
In Six Sigma methodology, a process operating at 4-sigma has approximately what defect rate per million opportunities (DPMO)?
Answer: 6,210 DPMO
A 4-sigma process produces approximately 6,210 defects per million opportunities, compared to 3.4 DPMO at the Six Sigma benchmark.
A laboratory's reagent blank consistently reads higher than expected. Which type of error is MOST likely present?
Answer: Constant systematic error
A consistently elevated reagent blank indicates constant systematic error (additive bias) affecting all results by the same absolute amount.
Which PDCA cycle step involves analyzing data collected during a process change to determine if the improvement was successful?
Answer: Check
The 'Check' (or Study) step of PDCA involves evaluating the collected data to assess whether the planned changes achieved the desired improvement.
A laboratory wants to reduce turnaround time for stat tests. Using Lean principles, which waste type does unnecessary transport of specimens represent?
Answer: Transportation
In Lean methodology, unnecessary movement of materials (including specimens) between locations is classified as the Transportation waste type.
When performing a method comparison study, which statistical measure indicates the degree of agreement between two quantitative methods?
Answer: Bias and slope from Deming regression
Deming regression accounts for error in both methods and provides slope (proportional error) and bias (constant error) to quantify method agreement.