Biochemical Testing

Question 1

Why is specimen testing performed?

Answer 1

To provide information for the appropriate treatment of patients

Question 2

Results should be accurate, _________, and correctly interpreted

Answer 2

Relevant

Question 3

List four scenarios for which testing is employed.

Answer 3

Diagnosis, prognosis, monitoring and treatment, and screening

Question 4

What specimen is most commonly used for analysis?

Answer 4

Serum (plasma)

Question 5

True or false: haemolysed samples are preferred for analysis.

Answer 5

False

Question 6

If a patient is on an IV drip, a _________ site must be used for drawing blood.

Answer 6

Remote

Question 7

List five controllable factors that may impact results.

Answer 7

Position of patient (impacts protein concentration), exercise (may increase creatinine kinase), time of day, lifestyle aspects, and diet

Question 8

What factors affecting results are outwith the medical scientist’s control?

Answer 8

Age, gender, environment of patient, and existing medical conditions

Question 9

______ tubes contain no anticoagulant or preservative, but may have a clot accelerator for serum samples.

Answer 9

Plain

Question 10

Green heparin tubes are suitable for most analyses, with little interference, and they prevent the formation of ________ from fibrinogen.

Answer 10

Fibrin

Question 11

Purple ethylenediaminetetraacetic acid (EDTA) tubes chelate _______, and are widely used.

Answer 11

Calcium

Question 12

Grey ________ ____________tubes are used in blood glucose measurements; they also inhibit metabolic pathways, and used as a preservative with another anticoagulant, such as potassium oxalate.

Answer 12

Sodium fluoride

Question 13

______ citrate tubes are used widely for coagulation studies, and can reversibly chelate calcium.

Answer 13

Blue

Question 14

List three fields which must be included on a sample request form.

Answer 14

Patient name, DOB, and ward number

Question 15

In specimen identification, ____________ is the technology of choice

Answer 15

Barcoding

Question 16

For which analysis must the sample be protected from light?

Answer 16

Bilirubin

Question 17

For all serum/plasma samples, separation should ideally be performed within ____ hours of the sample has being taken.

Answer 17

Two

Question 18

List the four features than an ideal analysis method should have.

Answer 18

Accuracy, precision, sensitivity, and specificity

Question 19

__________ indicates that a test will detect even very low levels of a particular analyte.

Answer 19

Sensitivity

Question 20

What term defines a test’s ability to be unaffected by interference?

Answer 20

Specificity

Question 21

Normality should be eschewed, in favour of patient results being described as being within, or outwith, the ___________ ________ (reference interval).

Answer 21

Reference range

Question 22

Diagnostic methods may also be referred to as ________ methods.

Answer 22

Clinical

Question 23

___________ _____________ measures the frequency of a test being positive, when a particular disease is present, a scenario known as a true positive (TP) result

Answer 23

Diagnostic sensitivity

Question 24

___________ ____________ measures the frequency of a test being negative, when a particular disease is absent (a true negative (TN) result).

Answer 24

Diagnostic specificity

Question 25

What is a predictive value?

Answer 25

A factor that plays a role in the ability of a test to diagnose disease is the prevalence of the condition in the population

Question 26

Calculating the ________/________ predictive value gives the ability to accurately detect disease in a defined population.

Answer 26

Positive/negative

Question 27

______ predictive value for a positive result (PPV) is very important, if the management or treatment of a patient with positive result would be dangerous to person with a false positive (FP).

Answer 27

High

Question 28

What type of test should have a high predictive value for negative (NPV) results, and indicate that for all positive results, further investigation must be undertaken?

Answer 28

Screening