Intro to lab medicine

Question 1

Accuracy

Answer 1

How closely the test results correspond to the gold standard. How often is test right

Question 2

Precision

Answer 2

How reproducible are the results

Question 3

Specificity

Answer 3

% of people without the disease and a negative test result. RULE IN (SPIN)

Question 4

Sensitivity

Answer 4

% of people who have the disease and have a positive test result. RULE OUT (SNOUT)

Question 5

Predictive value

Answer 5

Estimation of the probability of the presence or absence of disease

Question 6

False positive

Answer 6

Postive test result in a pt who does NOT have the disease

Question 7

False negative

Answer 7

Negative test result in a pt who DOES have the disease

Question 8

Prevalence

Answer 8

of cases of disease in a population

Question 9

Likelihood ratio

Answer 9

How likely is it that this test is going to help. LR+ >1 indicates test is associated with disease.
LR-

Question 10

Pretest probability

Answer 10

Probability of a pt having the disease before test results

Question 11

Posttest probability

Answer 11

Proportion of pts testing positive who truly have the disease

Question 12

Positive predictive value

Answer 12

% of people with a positive test who DO HAVE the disease

Question 13

Negative predictive value

Answer 13

% of people with a negative test who DO NOT HAVE the disease

Question 14

What is the equation for PPV

Answer 14

TP/TP + FP X 100

Question 15

What is the equation for the NPV

Answer 15

TN/TN + FN X 100

Question 16

Equation for sensitivity

Answer 16

TP/ TP + FN

Question 17

Equation for specificity

Answer 17

TN/ TN + FP

Question 18

What is a Critical PANIC value

Answer 18

It is a lab finding that is emergent and needs to be reported immediately to the clinician

Question 19

CLIA

Answer 19

Clinical laboratory improvement amendments

Question 20

CLIA waived test

Answer 20

Test that poses no or low risk for erroneous results. They are tests that are also approved for home use

Question 21

CLIA provider performed microscopy test

Answer 21

1. exam must be performed by a physician or mid-level
2. Moderate complexity
3. Instrument must be a microscope
4. Limited specimen handling is required

Question 22

Dipstick urinalysis

Answer 22

Thin strip placed in urine, results in a color change due to pH levels (also measures, proteins, ketones, bill, blood)

Question 23

Fecal occult blood testing

Answer 23

Smear stool on a Guiac card, tests for blood in the stool

Question 24

Urine pregnancy test

Answer 24

Pee on a dipstick, measures the presence of hCG

Question 25

Erythrocyte sedimentation test

Answer 25

ESR, used to detect inflammation associate with infections, cancer, autoimmune disorders

Question 26

Spun hematocrit

Answer 26

Measurement of RBC count, usually part of the CBC. Detects anemia

Question 27

Wet mount

Answer 27

Microscopic exam of vaginal discharge for bacterial vaginosis, candida, increased WBC

Question 28

Potassium hydroxide mount (KOH)

Answer 28

Microscopic exam of skin, hair, nails, vaginal discharge, confirms if there is a presence of a species (often fungal)

Question 29

Pinworm prep

Answer 29

Tape on anus, looking for helminths

Question 30

Capillary blood glucose

Answer 30

Monitors blood glucose (pin prick on finger)

Question 31

Ovulation test

Answer 31

Measure of LH (luteinizing hormone). Surges during ovulation and used to monitor menstrual irregularities, infertility.