MEASURES OF DISEASE FREQUENCY & MORBIDITY (PART 2)

Question 1

State of being symptomatic or unhealthy for a
disease/condition

Answer 1

MORBIDITY

Question 2

Presence of disease in a population

Answer 2

MORBIDITY

Question 3

Comorbidity-state of having 2
morbidities

Answer 3

Presence of disease in a population

Question 4

Two categories of measurement to describe
Morbidity Frequency of disease in a specified
population:

Answer 4

○ Incidence (new cases)
○ Prevalence (existing cases-old &
new)

Question 5

Occurrence of new cases of events (disease,
injury, death, etc.) in a population at risk over a
specified period of time.

Answer 5

INCIDENCE/INCIDENT CASES

Question 6

Number of transitions

Answer 6

INCIDENCE/INCIDENT CASES

Question 7

INCIDENCE/INCIDENT CASES Types:

Answer 7

○ Incidence Proportion/Risk
○ Incidence Rate/Person-Time Rate

Question 8

The proportion of initially disease-free
the population that develops new cases of the disease in a specified period of time

Answer 8

INCIDENCE PROPORTION/RISK

Question 9

Measures the probability that healthy people will
develop the disease during a specified time.

Answer 9

INCIDENCE PROPORTION/RISK

Question 10

INCIDENCE PROPORTION/RISK SYNONYMS

Answer 10

○ Attack Rate
○ Incidence Risk
○ Probability of Developing Disease
○ Cumulative Incidence

Question 11

INCIDENCE PROPORTION OF
OVARIAN CANCER
■ Numerator- _____________
■ Denominator- ____________

Answer 11

New cases of
ovarian cancer; Number of
women

Question 12

INCIDENCE PROPORTION/RISK CRITERIA NEEDED

Answer 12

○ Knowledge of health status of the study
population
○ Time of onset (acute vs chronic)
○ Specification of numerator
○ Specification of population “at risk”
○ Period of observation

Question 13

Denominator shouldn’t
include people who are ____________________

Answer 13

NOT
susceptible

Question 14

Number of persons at risk
varies over time. If so, consider
using population size at
________ of the time period.

Answer 14

mid-point

Question 15

PERIOD OF OBSERVATION FOR INCIDENCE PROPORTION/RISK

Answer 15

usually 1 year

Question 16

attack rate =

Answer 16

= (# of persons who suffered from attack/ total # of persons at risk of attack) 10^N

Question 17

form of incidence that measures the proportion of persons in a population who experience an acute health event during a limited period

Answer 17

attack rate

Question 18

total number of new cases divided by total population

Answer 18

overall attack rate

Question 19

number of persons who ate and became ill divided by total number of persons who ate the food

Answer 19

Food-specific attack rate

Question 20

spread of disease in a family, household, dwelling unit, dormitory, or similar circumscribed group

Answer 20

Secondary attack rate

Question 21

Secondary attack rate =

Answer 21

(number of cases among contacts of primary cases/ total number of contacts) x 10^n

Question 22

total number of contacts =

Answer 22

total population of household minus P^o cases

Question 23

AKA incidence density

Answer 23

INCIDENCE RATE/PERSON-TIME RATE

Question 24

Measure of incidence that incorporates time
directly into the denominator.

Answer 24

INCIDENCE RATE/PERSON-TIME RATE

Question 25

Estimates how quickly people are acquiring the disease

Answer 25

INCIDENCE RATE/PERSON-TIME RATE

Question 26

Calculated from long-term cohort follow up study

Answer 26

INCIDENCE RATE/PERSON-TIME RATE

Question 27

person-months/ persona years of observation

Answer 27

Person-time

Question 28

Risk period is short

Answer 28

INCIDENCE PROPORTION

Question 29

Likely to observe the whole period

Answer 29

INCIDENCE PROPORTION

Question 30

Risk period is long

Answer 30

INCIDENCE RATE

Question 31

Length of study follow up period will vary from study to study

Answer 31

INCIDENCE RATE

Question 32

Ex. food poisoning

Answer 32

INCIDENCE PROPORTION

Question 33

Ex. most cancers

Answer 33

INCIDENCE RATE

Question 34

Want to know what proportion of population became infected

Answer 34

INCIDENCE PROPORTION

Question 35

Want to know the rate at which new infections occur

Answer 35

INCIDENCE RATE

Question 36

What is the risk that an individual will develop the disease over a given time interval?

Answer 36

INCIDENCE PROPORTION

Question 37

How quickly or frequently does a disease occur in a population?

Answer 37

INCIDENCE RATE

Question 38

Not a measure of risk

Answer 38

PREVALENCE

Question 39

Proportion of persons in a population when a particular disease or attribute at a specified point in time/period

Answer 39

PREVALENCE

Question 40

Usually expressed as a percentage

Answer 40

. PREVALENCE

Question 41

Used to express burden of disease (new + old / pre existing case)

Answer 41

PREVALENCE

Question 42

Types of prevalence

Answer 42

○ Point prevalence ○ Period Prevalence

Question 43

Proportion of persons with a particular disease or attribute on a particular date.

Answer 43

Point Prevalence

Question 44

The proportion of persons with a particular disease or attribute at any time during the interval.

Answer 44

Period Prevalence

Question 45

"Do you currently have asthma?"

Answer 45

point of prevalence

Question 46

"Have you had asthma during the last (n) years?"

Answer 46

Period of prevalence

Question 47

Proportion/rate of a persons who develop a condition during a particular period

Answer 47

INCIDENCE

Question 48

New and pre-existing cases (Numerator)

Answer 48

PREVALENCE

Question 49

Proportion of persons who have condition at/during particular time period

Answer 49

PREVALENCE

Question 50

New cases only (Numerator)

Answer 50

INCIDENCE