Term
| Describe External quality assessment |
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Definition
| A full assessment by a qualified individual or review team carried out to maintain the quality of products. It is a periodic evaluation. |
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Term
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Definition
| Involves a set of activities used to ensure that the products meet the requirement and are improved |
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Term
| Describe Quality improvement |
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Definition
| It is the reduction of variability in process and product |
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Term
| Describe Quality assurance |
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Definition
| Set of Activities that ensures the quality levels of products are maintained. [image] |
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Term
| List 3 basic measures of dispersion |
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Definition
-Range
-Standard deviation
-Variance |
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Term
| What are the procedures which can be used to detect systematic errors |
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Definition
-Studies by exchange of the samples
-Use of certified reference materials
-Use of an alternative method |
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Term
| Difference between Precision and accuracy |
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Definition
-Precision measures how close are the results to one another in the same set of replicates.
-Accuracy measures how close are the results to the true value. |
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Term
| Describe the source of Instrumental errors and how to reduce it. |
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Definition
-Caused by incorrect calibration of the instrument, wearing and expansion of the glassware.
-Can be reduced by constant calibration of the instrument. |
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Term
| Describe the source of Method errors and how to reduce it. |
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Definition
-Poor understanding of the sample that is being analyzed. Resulting in contaminants or interferences.
-Reduced by applying alternative methods |
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Term
| Describe the source of Personal errors and how to reduce it. |
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Definition
-Caused by Insensitivity to color change
-Reduced by good practice |
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Term
| Explain the difference between relative error (Er) and coefficient of variation (RSD) |
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Definition
-Relative error is a measure of accuracy. [image]
-CV is a measure of precision. [image] |
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Term
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Definition
-Almost the same curve as the normal distribution
-Data points are evenly distributed around the mean.
-No outliers |
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Term
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Definition
-Sharp curve compared to the normal curve
-Data points are clustered around the mean
-There are significant outliers |
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Term
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Definition
-Flat curve compared to the normal curve
-Data points are scattered around the mean
-less outliers |
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Term
| List and discuss the eight dimensions of quality |
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Definition
-Properties- additional characteristics
-Durability- life span of product
-Reliability- How long it can work without any faulty
-Perceived Quality- Reputation
-serviceability- How easy to repair
-Aesthetic- looks, smell, feels
-Performance-Primary characteristics
-Conformance to standards- design standards |
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Term
| Explain Quality assessment |
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Definition
-It can be either Internal or external
-Internal: Is continuous assessment carried out by an individual within the organization that has the knowledge
-External: It is a periodic assessment carried out by a qualified individual or review team |
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Term
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Definition
| Process of selecting a portion of materials in a manner to represent the larger body of material. |
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Term
| Briefly discuss Limit of detection |
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Definition
-[image]
- Xb is the average of the blank measurements.
- Sb is the standard deviation of the replicates of blank measurements. |
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Term
| Briefly discuss Limit of quantitation |
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Definition
-[image]
- Xb is the average of the blank measurements.
- Sb is the standard deviation of the replicates of blank measurements. |
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Term
| Briefly discuss Selective sample |
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Definition
| Sample that is deliberately chosen by using a sampling plan that screens out materials with certain characteristics and selects those with relevant characteristics |
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Term
| Briefly discuss Sampling plan |
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Definition
| A predetermined procedure for the selection, withdrawal, presentation, transportation and preparation of the portions. |
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Term
| Briefly discuss precision |
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Definition
It is a measure of how close the results are to one another within a set of replicates
-Random errors, Repeatability |
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Term
| List the sources of contamination of samples in a laboratory environment |
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Definition
-Environmental conditions
-Containers (labelling)
-Contaminated tools
-Handling by personnel
-contaminated standards used to calibrate |
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Term
| Briefly describe how Random error affect experimental data |
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Definition
-Data is symmetrically scattered around the mean value
-Affects the precision of the results
-delt with statistically |
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Term
| Briefly describe how Systematic error affect experimental data |
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Definition
-Causes all data to be high or all data to be low
-Affects the accuracy of the data |
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Term
| Briefly describe how Gross error affect experimental data |
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Definition
-Results in outliers
-Detected by making replicates |
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Term
| State and describe the three measures of central tendency |
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Definition
Mean; Median; Mode
1)Symmetrical data: Median=Median=Mode
2)Positively skewed:Median>Median>Mode
3)Negatively skewed:Median |
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