Clinical Epi. Diagnosis II

Question 1

summarize the equations for sensitivity, specificity, PPV and NPV

Answer 1

Question 2

if the sensitivity of the test is high, most results will be ____; the number of ____ results will be low

Answer 2

if the sensitivity of the test is high, most results will be TP; the number of FN results will be low

Question 3

if sensitivity is high then you can ____ the disease if the test comes back negative

Answer 3

if sensitivity is high then you can RULE OUT the disease if the test comes back negative (bc few FN; most negatives are TN)

Question 4

if the specificity of the test is high, most results will be ___; the number of ___results will be low

Answer 4

if the specificity of the test is high, most results will be TN; the number of FP results will be low

Question 5

if specificity is high, then you can ____ the disease if the test comes back positive

Answer 5

if specificity is high, then you can RULE IN the disease if the test comes back positive (bc few FP; most positives are TP)

Question 6

summarize the rules of sensitivity and specificity

Answer 6

Question 7

Answer 7

sensitivity = TP / (TP + FN)

80%

Question 8

explain likelihood ratios (LR+ and LR-)

Answer 8

Question 9

describe parallell testing vs. serial testing

Answer 9

• parallel testing:
  
  • order several tests at once
  • useful for rapid assessment situations
• serial testing:
  
  • order next test on basis of prior test results
  • useful in clinical situations when assessment can be done over time or tests are expensive

Question 10

describe the 3 levels of prevention

Answer 10

• primary: reduce exposure to etiologic agent
• secondary: screen for asymptomatic disease with view of early treatment
• tertiary: prevention of recurrence or complications