PH: Principles of Screening Flashcards Preview

Year 3: CSP & PH > PH: Principles of Screening > Flashcards

Flashcards in PH: Principles of Screening Deck (7):
1

Define 'detection rate'

proportion of affected individuals with positive results.

2

Define 'false-positive rate'

1-specificity = proportion of unaffected individuals with positive results

3

How do you calculate OAPR? (odds of being affected given a positive result)

true positives : false positives

(likelihood ratio x prevalence as odds)

4

How is the odds of being affected given a positive result (OAPR) in screening affected?

It's affected be the prevalence of the disorder in a screened population, the higher the prevalence, the greater the OAPR

5

How do you calculate the likelihood ratio from screening results?

Detection rate/false-positive rate

6

How can you calculate the OAPR from likelihood and prevalence?

(likelihood ratio x prevalence as odds)

7

What's the difference between probability and odds?

probability presents the number of affected against the total population (1/5) whereas odds is the number of affected to the number of unaffected (therefore would be 1:6)