Immunology Week 2

An example of a preanalytical error is

specimen obtained from the wrong patient.

A patient s white blood cells (WBCs) are counted on an automated cell counter 10 times. The mean white count is 8000/mL, and the standard deviation (SD) is 300. What is the coefficient of variation (CV)?

3.8%

Quality assessment programs include

All of the above

The reference range is

All of the above

Nonanalytical factors in quality assessment include

Both A and B

Which of the following agencies administers the Clinical Laboratory Improvement Amendments?

Centers for Medicare and Medicaid Services

Quality control is the same as quality assurance.

False

Which of the following is true regarding good manufacturing practices (GMPs)?

GMPs are legal requirements established by the Food and Drug Administration.

The following hemoglobin results, reported in g/dL, are obtained on a hospitalized patient on 3 consecutive days: Day 1 Day 2 Day 3 14.3 11.5 14.4 The SD for this hemoglobin method was calculated in Question 18. A delta check was obtained on day 2. Controls were run as appropriate each day and were all within limits for this procedure. What is the most probable reason for the day 2 result when compared with those for days 1 and 3?

It may represent an error in patient identification.

A laboratory technologist decided she would like to bring her lab coat home for laundering because it had too many wrinkles when returned by the laboratory's laundry service. Is this practice acceptable?

No, because the laboratory is a biosafety level 2, and lab coats may not be removed

One of two controls that have been evaluated over the last 28 days gives a result on day 29 between 2 and 3 SDs of the mean; the other control is within 2 SDs of its mean. What is the correct procedure to follow?

Rerun the control and, if acceptable, continue with patients.

The antinuclear antibody (ANA) test is positive in almost all people who have systemic lupus erythematosus (SLE). It is also positive in some patients who do not have SLE. The antideoxyribonucleic acid (anti-DNA) test is positive only in people with SLE but not in all who do. Which of the following is true?

The ANA test is a good screening test, and anti-DNA test is a good confirmatory test.

A facility does not validate a refrigerator before use. What is a potential outcome?

The facility is in violation of current good manufacturing practices and could be cited by the Food and Drug Administration.

All accidents, even minor ones, must be reported to a supervisor.

True

If the control value in a determination is out of the acceptable range, faulty instrument or equipment may be the factor responsible.

True

Which of the following is an example of an unacceptable record-keeping procedure?

Using dittos in columns to save time

Employee training takes place:

after hiring and following implementation of new procedures.

Which of the following groups of patients should not be included in establishing moving averages using red cell indices?

chemotherapy patients

The tubing that brings the lyse reagent to the hemoglobin cuvette on an automated cell counter is pinched and not delivering any reagent. All hemoglobin values are greater than 20 g/dL. This represents what type of error?

constant systematic

Which of the following would most likely be associated with the situation described in Question 11?

fading light source

Accuracy

how close a measurement is to the true value

In safety training, employees must become familiar with all of the following except:

how to perform cardiopulmonary resuscitation on a donor or other employee.

For testing of moderate complexity, quality control requires

performing control procedures using at least two levels of control material for each day of testing.

Sensitivity is defined as the

proportion of subjects with the specific disease or condition who have a positive test result.

Specificity is defined as the

proportion of subjects without the specific disease or condition who have a negative test result.

Proper specimen collection and patient satisfaction are components of

quality assurance.

The control values for both controls for the prothrombin test were ranging between the mean and ±1 SD for the first 19 days of use. Starting on day 20, the values for both were consistently between +1 and +2 SDs. This is an example of a

shift.

Blood irradiators require all of the following safety procedures except:

that the user have a degree in radiology.

The precision limits of a method are defined by

the SD