Testing against an assigned value

Test if the value of the reference material is equal to the assigned value; that is the bias is zero.

You must have already completed the task:

Estimating the bias of a measurement system

It is possible for the bias from a study to be different to 0, but for the difference to be due to the random error in your study. The smaller your study, the larger the bias has to be to be declared statistically significant. Also, just because bias is statistically significant does not mean that it is of concern, it may still meet your allowable bias performance requirements.

Activate the analysis report worksheet.
On the Analyse-it ribbon tab, in the Bias group, click Test Equality.
The analysis task pane Trueness panel opens.
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.

Related tasks

Testing bias against allowable bias

Related information

CLSI. (2014b). User Verification of Performance for Precision and Trueness (EP15-A3). Clinical and Laboratory Standards Institute.

Available in Analyse-it Editions
Method Validation edition
Ultimate edition