Epidemiology

Question 1

Define incidence rate.

Answer 1

Number of new disease cases developing over specific time in defined population.

Question 2

Define prevalence.

Answer 2

Number of disease cases in defined population at one time.

Question 3

What is the equation for measuring incidence rate ?

Answer 3

Rate = number of new cases of disease / number of people at risk of developing that disease.

Question 4

What is the equation for measuring prevalence ?

Answer 4

Prevalence = number of cases of disease / total number of people in population.

Question 5

What allows for development of hypothesis of disease ?

Answer 5

Prevalence.

Question 6

Where should values be obtained from for calculating incidence rate ?

Answer 6

Longitudinal studies.

Question 7

Where should values be obtained from for calculating prevalence ?

Answer 7

Cross-sectional studies.

Question 8

What is SIMD ?

Answer 8

Scottish Index of Multiple Deprivation.
Area based index measuring Scottish neighbourhoods from most deprived to least deprived using a range of data from 7 factors of deprivation.

Question 9

What are the 7 factors of deprivation ?

Answer 9

Crime.
Eduction, skills and training.
Housing, living and working conditions.
Geographical access.
Health and healthcare services.
Employment status.
Income.

Question 10

What are the 5 properties of ideal epidemiological indices ?

Answer 10

Clear, unambiguous, objective and reproducible.
Indicate treatment need.
Correspond with clinical important changes in disease.
Be within ability of examiners and non-time consuming.
Amenable to statistical analysis and comparable to other studies.

Question 11

What is used as measurement for periodontal disease ?

Answer 11

CPITN.

Question 12

What index has been developed for measurement of dental caries ?

Answer 12

DMFT/dmft index.

Question 13

What does DMFT/dmft stand for ?

Answer 13

Decayed, missing or filled teeth - 0.32.

Question 14

What does DMFS/dmfs stand for ?

Answer 14

Decayed, missing or filled surfaces - 0-148.

Question 15

What does D3MFT/d3mft stand for ?

Answer 15

Decay into dentine.

Question 16

What does D1MFT/d1mft stand for ?

Answer 16

Decay into enamel.

Question 17

What are the limitations of dmft index ?

Answer 17

Teeth can be extracted for other reasons than caries.
Influenced by access i.e. inter proximal surfaces.
Difficulty differentiating FS from restoration.
Influenced by past disease activity.
Cannot be used for root caries.

Question 18

Define epidemiology.

Answer 18

Measurement of amount and distribution of disease and natural history of disease.

Question 19

Define risk factors.

Answer 19

Environmental, behaviour or biological factor confirmed by temporal sequences, usually increasing probability of disease occurring and if absent or removed, reduce probability.

Question 20

What are the three common indices of risk ?

Answer 20

Absolute.
Relative.
Attributable.

Question 21

Define absolute risk.

Answer 21

Incidence rate pop disease amongst people exposed to agent.

Question 22

Define relative risk.

Answer 22

Measurement of proportionate increase in disease rates of exposed group i.e. ratio of incidence rate in exposed and non-exposed group.

Question 23

Define attributable risk.

Answer 23

Difference between incidence rates in exposed and non-exposed groups.