CPM Test 3

Question 1

Best study design for screening test

Answer 1

Cohort

Question 2

Sensitivity

Specificity

Answer 2

TP/ TP+FN

TN/TN+FP

Question 3

Screening (snOUT)

Confirmatory (spIN)

Answer 3

Maximize sensitivity
SnOUT (Rule out)

Maximize specificity
Rule in

Question 4

Sequential Testing

Answer 4

Confirmatory test after + screening test

Dec sensitivity
Inc specifity

Question 5

PPV

NPV

Answer 5

TP/TP+FP, want high

TN/TN+FN

Question 6

Prevalence and test interpretation

High prev

Low prev

Answer 6

Higher PPV (+ indicates dz)
Lower NPV (Less likely to indicate no dz)

Low PPV (less likely to indicate dz)
High NPV (more likely to indicate no dz)

Question 7

Likelihood ratio

Answer 7

Likelihood that given test result would occur in pt w target disorder / likelihood that given test result would occur in pt wo target disorder

Question 8

P LR

N LR

Answer 8

Sens/ (1-Specificity)

(1-Sens)/Specificity

Question 9

Likelihood ratio values

Answer 9

1= unhelpful
moderately above/below 1= not that great
Well above/below 1= good test

Question 10

Dz that can be screened

Answer 10

Important health problem (high inc or mortality)
Treatment is + beneficial in early stages
Early dx improves survival/QOL

Question 11

Appropriate screening tests

Answer 11

Simple, safe, precise
Detect latent/early stage
Benefit outweighs harm

Question 12

Screening benefits

Answer 12

Know dz inc/mortality
NNS
Inc average life expectancy (limited usually)

Question 13

Screening harms

Answer 13

Adverse effects (discomfort/pain/radiation)
Overdiagnosis (yrs before manifestations/anx)
FP (anx, stigma, testing)

Question 14

Screening progam

Answer 14

Cost is balanced to HC expenditure
Systematic plan for monitoring program for quality assurance
Pt education about +/-

Question 15

Ratio of cost effectiveness

Answer 15

Incremental cost / health benefits

Question 16

Overdiagnosis bais

Answer 16

Overestimation of survival from screening caused by inclusion of pts w asymp dz that would not affect pt before they die of another cause

Question 17

Lead time bias

Answer 17

Overestimate survival from screening when survival when measured from time of dx

Question 18

Length bias

Answer 18

Overestimate survival caused by excess of slow progressive cases

Question 19

Screening Test Study Designs vs RCT

Answer 19

Good= observational (CC or cohort)
Volunteer bias tho

RCT- evaluation
challenging