Numerators

Question 1

What is case definition of disease? What is clinical diagnosis of disease?

Answer 1

CASE DEFINITION: A set of diagnostic criteria that must be fulfilled in order to identify a person as a case of a particular disease (may be suspected, probable, confirmed)
CLINICAL DIAGNOSIS: May be more related to immediate clinical management

Question 2

What are point or propagated (short-term) “epidemics”?

Answer 2

• Short-term exposures or diseases with short incubation and/or illness durations
• Short term changes that occur over limited time frames

Question 3

What are cyclic trends?

Answer 3

• Long or short term
• Sometimes seasonal, sometimes related to immigration, school year, military deployment
• e.g., influenza; myocardial infarction by day of the week

Question 4

What is the use of time clustering?

Answer 4

Time clustering data can be used to trace the ‘beginning’ of an outbreak, change in disease patterns, or introduction of causal agent

(time-space clustering also possible for interactions of time and place, such as migration or propagation in time and space of Nile virus)

Question 5

4 steps of Model of the Natural History of Disease?

Answer 5

1. Initiation of etiologic process
2. Initiation of pathologic process
3. Clinical detection (symptoms)
4. Outcome of disease

Question 6

What are the induction, the promotion and the expression periods in the Model of the Natural History of Disease?

Answer 6

Induction: between initiation of etiology and initiation of pathology

Promotion: between initiation of pathology and clinical detection

Expression: between clinical detection and outcome

Question 7

What is the nature and goal of primary prevention?

Answer 7

Before the initiation of pathology, to change the distribution of determinants of disease in the population

Goal: reduce incidence (prevent or postpone)

Question 8

What is the nature and goal of secondary prevention?

Answer 8

After the initiation of pathology, but before the clinical detection, to detect the disease early and start treatment early

Goal: reduce prevalence (improve prognosis, shorten duration of disease, prolong life)

Question 9

What is the nature and goal of tertiary prevention?

Answer 9

After the clinical detection, treatment and rehabilitation

Goal: reduce the impact of the disease (improve quality of life)