week 1 l

Question 1

What are blood donations tested for

Answer 1

ABO Rh blood types, antibodies to certain virus and chagas enzyme

Question 2

what is the universal precauston

Answer 2

treat all human blood and certain body fluid as if they are know to be infectious with blood born pathogen

Question 3

what is lab medicine

Answer 3

testing services, and practices for assessment, diagnosis, treatment, management or prevention of health related conditions

Question 4

what are laboratory tests

Answer 4

test or examination of human body materials for purpose of making patient care decisions or improving public health.

Question 5

what is screening

Answer 5

test asymptomatic to detect diseas before it shows symptoms

Question 6

example of screeening

Answer 6

pap, hiv, tB, PKU, colonoscopy

Question 7

objective of populations screeningq

Answer 7

ultimatly to reduce mortality and morbitity, but immediatley to classify likely or unlikely to have disease

Question 8

Natural history of disease

Answer 8

sequence of development from the first pathological change untill disease or death

Question 9

what is induction?

Answer 9

time to disease initiation

Question 10

incubation

Answer 10

time to get to have symptoms of infections disease

Question 11

latency

Answer 11

time untill detection or infectiousness

Question 12

what makes a disease suitable for screening?

Answer 12

better outcomes if treated early, test can detect disease before symptoms and consequences are serious if untreated

Question 13

what makes a test suitable for screening?

Answer 13

can detect before symptoms show, safe, accurate, cost effective

Question 14

what make screening program suidable?

Answer 14

gets target population, quality control of testing, good follow up for positives and efficient

Question 15

what makes screening program a good use of resources

Answer 15

low cost, low follow up costs, cost of treatment, benefits vs alternatives

Question 16

what are the 4 principals of a screening program

Answer 16

For suitable disease with a suitable test for it, suitable program that makes good use of resources

Question 17

Reliable test is what?

Answer 17

repeatability ,same result each time, non necessarily right

Question 18

what is a valid test

Answer 18

gets the correct result

Question 19

what is sensitive

Answer 19

correctly classify positive cases

Question 20

specificity

Answer 20

correclty classify non cases

Question 21

how is sensitivity found

Answer 21

cases that were correctly found positive over all truly positive cases tested (this includes the false neg)

Question 22

how is specivicity found

Answer 22

cases that were found correctly negative over total of truly negative or non cases (this would include the false positives)

Question 23

what test is sensitivity more valued than spedificity

Answer 23

HIV because the risk with failure to diagnosis is high.

Question 24

what test is specificity most important?

Answer 24

cystic fibrosis because disease is potential fatal with no therapy, it?s a death sentence.

Question 25

what is the predicted value?

Answer 25

probability of those tested who are correctly classified.

Question 26

how is predictive value determined PPV

Answer 26

goind the other way with the box, all true positives over total positives, even though some are wrong

Question 27

How is negative predictive value determined NPV

Answer 27

all true negatives over all tested negatives although some are wrong

Question 28

what happens to positive predictive value when prevalence of the disease increases

Answer 28

the positive predictive value goes way up even if sensitivity and specificity doesn’t change

Question 29

What is the hypothesis deduction for establishing diagnosis?

Answer 29

Only asking for tests for disease or condition that is a possibility to avoid false positives.

Question 30

what is a medical alogorigthm

Answer 30

decision tree, if pos do this or that.

Question 31

How is prognosis determined

Answer 31

location, receptors, cell division rate, gene espression

Question 32

what are the reference ranges for a healthy individual

Answer 32

plus or minus two standard deviations from the mean.

Question 33

What should you remember about reference range

Answer 33

some clinically normal may have disease, population size, does it represent your patient, random some diseased will have normal labe results.

Question 34

what can affect lab tests?

Answer 34

fasting, time of day, age, gender

Question 35

where do invalid labe test most often come from?

Answer 35

transport, patient id, test collection procedures, 62 percent

Question 36

what are some post analytical errors

Answer 36

misinterpret result, error of report or data entry

Question 37

what should I think about before ordering test?

Answer 37

Why, consequences, will it narrow disease down, can I interpret results, will results affect patient management behavior