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1- Behavioral Science 1 (2 Hours & 48 minutes)

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   Content of this Session
    • Epidemiologic measures
    • Incidence and Prevalence
    • Crude, Specific, and Standardized Rates
    • Interpreting Diagnostic and Screening Tests
    • Pre-test Probabilities
    • Post-test Probabilities
    • The relationship between the screening test probability
    • Selecting Screening Test Cutoff Values
    • Receiver Operating Characteristic (ROC) Curve

 

 

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[h] Hematology & Oncology System Flashcards

[i] Master this session in just 5 minutes.

[q] ……. is the rate at which new events occur in a population and should not include old cases or dead cases in the denominator?

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[Qq]Mnemonic: Incidence is the rate at which new cases coming in.

[q] …… is the cumulative incidence of infection in a group of people observed over a period of time during an epidemic, usually in relation to foodborne illness?

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[q] ……. is the rate at which All persons who experience an event in a population (old and new cases) and should not include dead cases in the denominator?

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[q] …… is prevalence during a particular “point in time“.

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[q] …… is prevalence during a specified period or “span of time”.

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[q] Prevalence ≈ incidence for ……..? Prevalence > incidence for …….?

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[q] How do prevalence and incidence change if an effective prevention, such as a vaccine (primary prevention), is discovered?

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[q] How do prevalence and incidence change if cure (secondary prevention) is discovered?

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[q] How do prevalence and incidence change if  an effective therapy prolongs life discovered, but does not cure?

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[q] …… the probability of correctly identifying a case of disease?

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[Qq]

Everyone in the calculation is a diseased person.

TP on top divided by everything in the same column.

SEN = 750/(750 + 250) = 750/1,000 = 75%

[q] …. is the probability of correctly identifying disease-free persons.

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TN in top divided by everything in the same column.

SPEC = 950/(950 + 50) = 950/1,000 = 95%.

[q] ….. is the probability of disease in a person who receives a positive test result?

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PPV = 750/(750 + 50) = 750/800 = 93.8%

[q] …….. is the probability of no disease in a person who receives a negative test result?

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NPV = 950/(950 + 250) = 950/1,200 = 79.2%.

[q] What is the effect of increased prevalence on sensitivity? On positive predictive value?

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[q] What is the effect of the pretest probability on negative predictive value?

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[q]

1. What is the Point of optimum seNsitivty & point of optimum Negative predictive value?

 

2. What is the Point of optimum sPecificity & point of optimum Positive predictive value?

3. What is the effect of lowering the cuttoff point from B –>A?

4. What is the effect of raising the cuttoff point from B –>C?

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2. C

3. ↑ seNsitivty & point of optimum Negative predictive value. ↓ sPecificity & point of optimum Positive predictive value.

↓ seNsitivty & point of optimum Negative predictive value.  ↑ sPecificity & point of optimum Positive predictive value.

 

[q] Decreased overlap between the healthy and diseased population curves decreases both the number of FP and FN, What is the effect of this on sensitivity and specifity?

 

 

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[q] What is the best screening test of (A,B, C, D, E)?

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