Lecture 5: Population Screening

Question 1

What is population screening?

Answer 1

Evaluation offered to all individuals within a target group, usually defined by age and sex.

Question 2

What is the goal of population screening?

Answer 2

Looking for signs of or diagnosing a disease BEFORE symptoms develop in order to decrease mortality.

Question 3

What differentiates a diagnostic eval from a screening eval?

Answer 3

Diagnostic is to confirm the presence or absence of disease when symptoms are PRESENT.

Question 4

What must a screening test do to be considered effective?

Answer 4

Improve mortality.

Question 5

What is lead-time bias?

Answer 5

The time period between detection of a disease and its clinical presentation.
AKA
You detect it later than the real onset, so the survival time seems longer.

Question 6

What is length-time bias?

Answer 6

Overestimation of survival duration due to the relative excess of cases detected that are slowly progressing.

Question 7

What is misclassification bias?

Answer 7

Systematic error when a participant, value, or attribute is classified into the wrong category, altering the outcomes of the study.

Question 8

What determines if we should screen for a disease or not?

Answer 8

• Is the condition a pertinent health problem?
• Is the epidemiology of the condition understood?
• Is the test simple, safe, reliable, and valid?
• Is the test acceptable to the population and health providers?
• Do we have a protocol in place for an abnormal screening test?
• Do we have improved outcomes from screening?
• Do we have a financial benefit from screening?

Question 9

Can insurance companies deny coverage based on positive genetic testing?

Answer 9

• Health: NO
• Life: YES