1.
State what is meant by a random error.
[1 mark]
- varies unpredictably
JD SCIENCE
Data collection, analysis and errors
Indicative marking points. Award marks for equivalent scientific or mathematical wording. Do not issue this sheet with the student worksheet.
2.
State what is meant by a systematic error.
[1 mark]
- shifts all results the same way
3.
State what is meant by a transcription error.
[1 mark]
- wrong number copied into LIMS
4.
State what is meant by an instrument fault.
[1 mark]
- drift, blockage, lamp failure
5.
State what is meant by sample mix-up.
[1 mark]
- wrong ID or swapped tubes
6.
State what is meant by Westgard rules (idea).
[1 mark]
- QC rules that detect error
7.
State what is meant by a control chart.
[1 mark]
- plots QC over time
8.
State what is meant by root-cause analysis.
[1 mark]
- 5 whys / fishbone
9.
State what is meant by data integrity ALCOA.
[1 mark]
- attributable, legible, contemporaneous, original, accurate
10.
State what is meant by process improvement.
[1 mark]
- change the SOP, training or equipment
11.
Pat is asked about a random error in a Pearson Laboratory Sciences paper.
(a) [2 marks]
- reduced by repeats and a mean
(b) [3 marks]
- shown by scatter
12.
Pat is asked about a systematic error in a Pearson Laboratory Sciences paper.
(a) [2 marks]
- wrong calibration, indicator, temperature
(b) [3 marks]
- not fixed by averaging
13.
Pat is asked about a transcription error in a Pearson Laboratory Sciences paper.
(a) [2 marks]
- prevent with instrument interfaces
(b) [3 marks]
- Assignment 3 style issue
14.
Pat is asked about an instrument fault in a Pearson Laboratory Sciences paper.
(a) [2 marks]
- QC fails, flags on the printout
(b) [3 marks]
- quarantine the instrument
15.
Pat is asked about sample mix-up in a Pearson Laboratory Sciences paper.
(a) [2 marks]
- chain of custody failed
(b) [3 marks]
- re-collect if possible
16.
Pat is asked about Westgard rules (idea) in a Pearson Laboratory Sciences paper.
(a) [2 marks]
- 1-3s, 2-2s
(b) [3 marks]
- reject the run if failed
17.
Results 10.1, 10.3, 12.9, 10.2. Which is the likely outlier?
[3 marks]
- Final answer: 12.9
18.
Mean of the three concordant values 10.1, 10.3, 10.2
[3 marks]
- Final answer: 10.2
19.
A QC limit is 5.00 ± 0.20. Is 5.25 acceptable?
[3 marks]
- Final answer: no
20.
SD idea: values 4, 6, 8. Mean and range?
[3 marks]
- Final answer: mean 6, range 4
21.
A LIMS audit finds 6 of 120 entries edited. Percentage?
[3 marks]
- Final answer: 5%
22.
Two analysts differ by 0.40 on a mean of 20.0. Percentage difference?
[3 marks]
- Final answer: 2%
23.
Pat carries out a T-Level occupational task on laboratory data, LIMS and error. This is a typical Pearson required-practical style question.
(a) [2 marks]
- Independent: the factor being investigated
- Dependent: the measured result or quality check
(b) [2 marks]
- follow the SOP and keep other variables constant
- so the test is fair / only one variable is changed
(c) [2 marks]
- not recording the batch/lot number or operator ID
24.
Pat carries out writing or following an SOP for laboratory data, LIMS and error. This is a typical Pearson required-practical style question.
(a) [2 marks]
- Independent: a step in the method
- Dependent: whether the acceptance criteria are met
(b) [2 marks]
- same calibrated instrument
- so the test is fair / only one variable is changed
(c) [2 marks]
- skipping a verification check
25.
Pat carries out a COSHH / risk-assessment review for laboratory data, LIMS and error. This is a typical Pearson required-practical style question.
(a) [2 marks]
- Independent: hazard
- Dependent: control measure effectiveness
(b) [2 marks]
- same PPE and waste route
- so the test is fair / only one variable is changed
(c) [2 marks]
- using expired reagents or the wrong waste stream
26.
Pat carries out data review in a LIMS or quality log for laboratory data, LIMS and error. This is a typical Pearson required-practical style question.
(a) [2 marks]
- Independent: sample ID
- Dependent: result vs specification
(b) [2 marks]
- same calculation method
- so the test is fair / only one variable is changed
(c) [2 marks]
- transcription error between the instrument and the LIMS
27.
Compare a random error with an instrument fault.
[4 marks]
- varies unpredictably
- drift, blockage, lamp failure
- state one workplace implication
28.
Compare a systematic error with sample mix-up.
[4 marks]
- shifts all results the same way
- wrong ID or swapped tubes
- state one workplace implication
29.
Compare a transcription error with Westgard rules (idea).
[4 marks]
- wrong number copied into LIMS
- QC rules that detect error
- state one workplace implication
30.
Compare an instrument fault with a control chart.
[4 marks]
- drift, blockage, lamp failure
- plots QC over time
- state one workplace implication
31.
Apply your knowledge of a control chart to this situation: warning and action limits
[3 marks]
- warning and action limits
32.
Apply your knowledge of root-cause analysis to this situation: find the system cause
[3 marks]
- find the system cause