CLC Data Analysis & Reporting Techniques 3

Question 1

A laboratory is implementing a new reporting format for critical values. Which element is most essential to include in the critical value notification documentation?

Accepted Answer

The name of the person who received the notification and the time of notification

Answer

Critical value notification documentation must include who received the report and the time, as this creates an auditable record of the communication loop.

Question 2

Which of the following best describes the purpose of a Bland-Altman plot in laboratory method validation?

Accepted Answer

It graphically displays the agreement between two measurement methods by plotting the difference against the mean

Answer

A Bland-Altman plot visualizes the mean difference (bias) and limits of agreement between two methods, revealing whether they can be used interchangeably.

Question 3

A laboratory director requests a Six Sigma analysis of a glucose assay. The assay has a bias of 1.5% and a CV of 2.0%, with an allowable total error of 10%. What is the Sigma metric?

Accepted Answer

4.25

Answer

Sigma = (TEa - |bias|) / CV = (10 - 1.5) / 2.0 = 8.5 / 2.0 = 4.25, indicating a good but improvable process.

Question 4

When calculating the predictive value of a positive test result in a low-prevalence population, which phenomenon must a CLC account for?

Accepted Answer

The base rate fallacy (low PPV despite high sensitivity and specificity)

Answer

In low-prevalence populations, even highly sensitive and specific tests yield a low positive predictive value (PPV) because false positives outnumber true positives.

Question 5

A laboratory quality report shows a consistent inter-laboratory bias when comparing results with a reference method. This type of error is best classified as:

Accepted Answer

Systematic error

Answer

A consistent directional bias between a laboratory method and a reference method is a systematic error, affecting accuracy rather than precision.

(CLC) Certified Laboratory Consultant Practice Test

(CLC) Certified Laboratory Consultant Practice Test

CLC Data Analysis & Reporting Techniques 3