8/9/16 Lab Medicine - Carayannopoulos

Question 1

diagnostic test vs screening test

Answer 1

diagnostic test : given when pt shows signs/symptoms

screening test : given to asymptomatic pts

diag is performed after +screen!

Question 2

3 phases of diagnostic testing

Answer 2

1. pre-analytic phase

• develop clinical question, pick test, order test, collect specimen
• 65-75% of all errors in this phase

2. analytic phase
   * sample prepared, sample analyzed, result verified
3. post-analytic phase
   * result reported, result interpreted in context, action taken, patient care affected

Question 3

ROC curve

Answer 3

receiver operator characteristic curve

compares diag test performance at diff cutoff points

• plot of TP rate against FP rate for diff possible cutoffs of a test
• shows sn/sp tradeoff
• area under curve (AUC) is measure of test accuracy

Question 4

Virchow vs. Rokitansky autopsy

Answer 4

Virchow: organs removed one by one

Rokitansky: organs removed en masse