Testing precision against a performance claim
Test if the precision matches a performance claim.
You must have already completed the task:
You should use this procedure when you already have a performance claim from a manufacturer's package insert, and you want to test whether your precision is significantly greater than the claim. It is possible for the precision from a study to be greater than the claim, but for the difference to be due to the random error in your study.
- Activate the analysis report worksheet.
-
On the Analyse-it ribbon tab, in the MSA group, click Test.
The analysis task pane Precision panel opens.
- In the Hypothesized imprecision grid, alongside each level, enter the performance claim as the SD in measurement units or the CV as a percentage (suffix with % symbol).
- Optional:
In the Significance level edit box, type the maximum probability of rejecting the null hypothesis when in fact it is true (typically 5% or 1%) and if required select the Familywise error rate check box.
Note: CLSI EP15 uses a 5% familywise significance level so the overall significance level is a maximum of 5% regardless of the number of comparisons (for example, for 1 level the significance level is 5%, for 2 levels the significance level is 5%/2 = 2.5% for each level, for 3 levels the significance level is 5%/3 = 1.6% for each level).
- Click Recalculate.
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