Chapter 6

Question 1

epidemiological transition

Answer 1

describes the changing pattern of disease that has been seen in many countries as they have experienced social and economic development. Its central message is that prior to social and economic development, communicable diseases—or microbial agents, using the term from actual causes—represent the dominant cause of disease and disability.

Question 2

A limited number of basic strategies being used that are part of the population health approach, including:

Answer 2

■ Screening for early detection and treatment of disease
■ Multiple risk factor interventions
■ Identification of cost-effective treatments
■ Genetics counseling and intervention
■ Research

Question 3

screening for disease

Answer 3

implies the use of tests on individuals who do not have symptoms of a specific disease (asymptomatic individuals)

Question 4

Four criteria need to be fulfilled for an ideal screening program

Answer 4

1. The disease produces substantial death and/ or disability.
2. Early detection is possible and improves outcome.
3. There is a feasible testing strategy for screening.
4. Screening is acceptable in terms of harms, costs, and patient acceptance.

Question 5

lead-time bias

Answer 5

early detection without improved outcome

Question 6

False positives

Answer 6

individuals who have positive results on a screening test but do not turn out to have the disease.

Question 7

False negatives

Answer 7

those who have negative results on the screening test but turn out to have the disease.

Question 8

true positives

Answer 8

individuals who have a positive test and also have the disease.

Question 9

Bayes’ theorem

Answer 9

a mathematical formula that has very practical applications to interpreting the meaning of diagnostic and screening tests. Bayes’ theorem provides the connection between the probability of disease before a test is conducted, or the pretest probability of disease, and the probability of disease after knowing whether the test result is positive or negative, or the posttest probability of disease.

Question 10

sequential testing

Answer 10

aka consecutive testing. This approach implies that an initial screening test is followed by one or more definitive or diagnostic tests.

Question 11

Sequential testing by definition misses

Answer 11

those who have false negative results because when a negative test occurs, the testing process is over, at least for the immediate future.

Question 12

multiple risk factor reduction

Answer 12

this strategy intervenes simultaneously in a series of risk factors, all of which contribute to a particular outcome, such as cardiovascular disease or lung cancer. Multiple risk factor reduction is most effective when there are constellations, or groups of risk factors that cluster together in definable groups of people.

Question 13

Cost-effectiveness

Answer 13

a concept that combines issues of benefits and harms with issues of financial costs. It starts by considering the benefits and harms of an intervention to determine its net-effectiveness or net benefit.

Question 14

Net-effectiveness

Answer 14

implies that the benefits are substantially greater than the harms, even after the value (or utility), as well as the timing of the harms and benefits, are taken into account. Only after establishing net-effectiveness do we take into account the financial costs.

Question 15

Potential uses of genetic testing has been categorized as follows:

Answer 15

• Predicting the risk of a disease
• Pharmacogenetic testing
• Reproductive Genetic Testing

Question 16

Predicting the risk of a disease

Answer 16

Predictive genetic testing identifies gene variants that increase an individual’s risk of developing a disease.

Question 17

incomplete penetrance

Answer 17

For many diseases having a gene associated with disease may only slightly increase the chance of developing the disease.

Question 18

Pharmacogenetic testing

Answer 18

provides information about how individuals will respond to drugs. Pharmacogenetics has the potential to help identify the best drug(s) to use for a condition such as cancer and to prevent use of drugs or adjust the dose of a drug when an individual has a high likelihood of an allergic reaction or side effect from a drug.

Question 19

Reproductive Genetic Testing

Answer 19

aims to identify people who are at increased risk for having a child who has a genetic disease.

Question 20

Carrier tests

Answer 20

are used to identify people who are at increased risk for having a child who has a genetic disease. Carrier tests usu- ally aim to identify people who are heterozygous for or “carry” one variant copy and one normal copy of a gene for a disease that requires both copies of the gene to clinically express the disease. Carriers generally do not show signs of the disease, but they have the ability to pass on the variant gene to their children.