MEASURES OF MORTALITY AND OTHER DISEASE IMPACT

Question 1

Morbidity

Answer 1

presence of disease in a population.

Question 2

Mortality

Answer 2

The state of being susceptible to death

Question 3

• Measure of the number of deaths in a particular population per unit of time

• Serves as a measure of “disease severity”; surrogates for incidence rates

Answer 3

Mortality Rate

Question 4

MORTALITY RATES

Answer 4

1. Annual death rate (mortality rate) from all causes
2. Specific death rate (annual death rate w/restriction)
3. Case-Fatality Rate
4. Proportionate mortality (proportion,not a rate)

Question 5

Annual death rate from all causes formula

Answer 5

Total no. of deaths from all causes in 1 year/ No. of persons in the population at mid-year (x1000)

Question 6

Specific death rate(annual death rate w/restriction)

Answer 6

• Age-specific mortality rate
• Disease-specific mortality rate
• Cause-specific mortality rate
• Other demographics:gender, race, etc.

Question 7

Case-Fatality rate

Answer 7

• Percentage of people who have a certain disease and who die within a certain time after disease diagnosis

• Use date of diagnosis as a surrogate measure for date of
disease onset

Question 8

Case Fatality Rate Formula

Answer 8

no. of individuals dying during a specified period of time after disease onset or diagnosis/ no. of individuals with the specified disease (x100)

Question 9

Numerator of Mortality Rate

Answer 9

Number of death from all causes or number or death from specific cause of death.

Question 10

Numerator for Case Fatality Rate

Answer 10

• Restricted to deaths only from specific disease.
• Technically not a rate, but a percentage.

Question 11

Denominator for Mortality Rate

Answer 11

Entire population at risk of dying from the disease.

Question 12

Denominator for Case Fatality Rate

Answer 12

Limited to those who already have the disease of concern (Measure the severity of disease).

Question 13

Proportionate mortality (proportion, not a rate)

Answer 13

• Describes the proportion of deaths in a specified population over a period of time, attributable to different causes

• Each cause is expressed as a percentage of all deaths

• Sum of the causes must add to 100%

Question 14

Formula for Proportionate Mortality

Answer 14

no. of deaths/ total deaths(x100)

Question 15

MORTALITY INDICES

Answer 15

1. YPPL
2. DALY

Question 16

YPLL

Answer 16

Years of Potential Life Lost = 75 years;

• Measure of premature mortality, or early death

• U.S.A (and most developed nations) = 75 years of age

• Philippines (as of 2020) = 72.12 average years of life

Question 17

DALY

Answer 17

Disability-Adjusted Life Year (DALY)

• Another index of disease burden

• 1DALY=1 lost year of healthy life

Question 18

FORMULA FOR DALY

Answer 18

• Formula: years of life lost to premature deaths + years lived with a disability of specified severity and duration

Question 19

Risk

Answer 19

Proportion of persons who are unaffected at the beginning of a study period, but who experiences a risk event DURING the study period

Question 20

Cohort

Answer 20

Constitutes the people at risk for the event at the BEGINNING of the study period

Question 21

Case fatality ratio

Answer 21

proportion of clinically ill persons who die

Question 22

Pathogenicity of the organism

Answer 22

proportion of infected
persons who are clinically ill

Question 23

Infectiousness of the organism

Answer 23

proportion of exposed persons who become infected

Question 24

Force of mortality (FOM)

Answer 24

•Represents the instantaneous rate of mortality at a certain age measured on an annualized basis
•Force of mortality:greatest in A,lowest in B,intermediate in C

Question 25

Rate

Answer 25

• Number of events that occur in a defined time period divided by the average number of people at risk (ideally: midyear) for the event during the period under study

• Often used to measure risk

Question 26

Crude Death Rate

Answer 26

• Number of deaths occurring among the population of a given geographical area during a given year, among a population of 1,000 people

• “Crude” because all ages are represented

Question 27

Instantaneous death rate /hazard rate

Answer 27

When death rate is expressed as describing reality at an instant in time (probability of death over a short period)

Question 28

A rate is a good approximation of risk if the:

Answer 28

• Event in the numerator occurs only once per individual during the study interval

• Proportion of the population affected by the event is small (e.g.<5%)

• Time interval is relatively short

Question 29

Incidence density

Answer 29

if event in the numerator occurs
more than once during the study

Question 30

SPECIFIC TYPES OF RATES

Answer 30

1. Incidence rate
2. Prevalence rate
3. Incidence density