Lab methods

Question 1

where is lab data used

Answer 1

94% medical record
60-70% clinical decision
37% practice guidelines

Question 2

steps in lab testing (6)

Answer 2

1. symptoms
2. examination
3. test request
4. lab analyses
5. diagnosis
6. treatment

Question 3

3 ways to keep tests accurate

Answer 3

1. internal QQ
2. validation and notification
3. quality assurance - external

Question 4

5 lab medicin disciplines

Answer 4

1. receptionist - handing and data entry
2. phlebotomist - sample collection
3. techs - helper monkey
4. clinical lab scientist - performs science
5. pathologist - interprets

Question 5

5 specialties in lab medicine

Answer 5

1. biochem
2. hematology
3. microbiology
4. pathology
5. molecular diagnosists

Question 6

3 main steps of lab testing proces

Answer 6

1. pre-analytical
2. analytical
3. post-analytical

Question 7

3 preanalysis steps and issues

Answer 7

1. doc orders test - right test for right patient
2. sample obtained - type, fasting, time, exposure
3. transport - conditions

Question 8

2 steps to analysis

Answer 8

1. perform quality control

2. measure marker - turn around based on need and availability

Question 9

2 parts of post-analysis

Answer 9

1. lab reports reults

2. physician interprets

Question 10

2. ways of releasing results and isses

Answer 10

1. automatic

2. manual - human error

Question 11

2 ways to interpret result

Answer 11

1. reference interval (within 2 SD or 95% of pop)

2. deciion limit - point after which is clinical

Question 12

define precision

Answer 12

agreement between repeated test (same spot)

Question 13

define accurate

Answer 13

agreement between true value and measured value (close to bullseye)

Question 14

define bias

Answer 14

deviation from true value

Question 15

2 types of bias

Answer 15

true bias - not the true value

relative bias - 2 diff results, but don’t know which is accurate

Question 16

define biol. variation

Answer 16

fluctutuation of fluids over short and long times

Question 17

biol variation for Na, cort. , PTH

Answer 17

Na - 0.7%
Cort - 20.9%
PTH - 25.3%

Question 18

what is specificity

Answer 18

those without the disease that have a neg result (TN/TN+FP)

Question 19

what is sensitivity

Answer 19

those with the disease the that have positive result (TP/TP+FN)

Question 20

5 uses of lab tests and

Answer 20

1. screening - want sensitive test
2. diagnosis - want to detect everyone with specific disease - specific test
3. prognosis - predict outcome
4. staging - treatment planning
5. monitoring - treatment success