Method Evaluation & Quality Control

is used to verify the acceptability of new methods prior to reporting patient results.

The foundation for monitoring performance (known as QC)

The three most commonly used descriptions of the center of a data set

There are four commonly used descriptions of spread:

the most frequently used measure of variation.

represent the “average” distance from the center of the data (the mean) and every value in the data set.

a calculation to show the number of SDs a value is from the target mean.

Three factors are generated in a linear regression

is a measure of the strength of the relationship between the two methods.

indicates that both variables increase and decrease together,

indicates that as one variable increases, the other decreases.

An r value of ___ indicates no relationship,

r = ___ indicates a perfect relationship.

An alternate approach to visualizing paired data is the difference plot, which is also known as the:

The difference between test and reference method results is called

is present in all measurements and can be either positive or negative, typically a combination of both positive and negative errors on both sides of the assigned target value.

influences observations consistently in one direction higher or lower

exists when there is a continual difference between the test method and the comparative method values, regardless of the concentration.

exists when the differences between the test method and the comparative method values are proportional to the analyte concentration.

TRUE/FALSE: The CLIA final rule requires that waived tests simply follow the manufacturer’s instructions.

Systematic error can be due to constant or proportional error and is estimated from three types of study:

Ability of a method to detect small quantities or small changes in concentration of an analyte.

Ability of a method to detect only the analyte it is designed to determine, also known as cross-reactivity.

Also known as linear or dynamic range. Range of analyte concentrations that can be directly measured without dilution, concentration, or other pretreatment.