Mortality Rates powerpoint for genetics courses at medical school

genetics powerpoint for students studying medicina

1. Measures of Mortality
&
Mortality in Different Populations

2. Mortality is a term which
means “death” or describes
death and related issues

3. Mortality Table

4. Selected Mortality Rates

5. Rates
•With rates, the numerator is included
in the denominator
•Rate is the number of or frequency of
a disease per unit size of population

6. Ratios
•Ratio –the relation in number,
degree or quantity existing between
two similar things
25 ♀: 30 ♂
•Ratio as a fraction
25/30 or 5/6

7. Proportions
•Compare like populations or like
illnesses within a population
For example, 40 children are currently
ill with measles, while 80 children all
together have or have had the measles

8. Mortality
•Deaths; describes death; related
issues
•Graunt
1600s –Bills of Mortality
•Farr (1807-1883)
Registrar general; vital statistics
Causes
Registration

10. Types of Mortality Rates/Ratio
•crude death rates
•infant mortality rates (ratio)
•neonatal mortality rates
•postneonatal mortality rates
•perinatal mortality rates
•fetal death rates
•abortion rates
•maternal mortality rates
•adjusted mortality rates
•standardized mortality ratio
•specific death rates
•proportionate mortality rate-case fatality rate
•mortality crossover –mortality time trends
Your Assignment:
familiarize yourself
with the definitions
of these terms

11. Measure Numerator Denominator 10
n
Crude deathrateTotal number of deaths during a
given time interval
Mid-interval population 1,000 or
100,000
Cause-specific
death rate
Number of deaths assigned to a
specific cause during a given time
interval
Mid-intervalpopulation 1000 or
100,000
Proportionate
mortality
Number of deaths assigned to a
specific cause during a given time
interval
Total number of deaths from all
causes during the same time
interval
100 or
1,000
Death-to-case
ratio
Number of deaths assigned to a
specific cause during a given time
interval
Number of new cases of same
disease reported during the
same time interval
100
Neonatal
mortality rate
Number of deaths among children
< 28 days of age during a given
time interval
Number of live births during the
same time interval
1,000
Postneonatal
mortality rate
Number of deaths among children
28–364 days of age during a
given time interval
Number of live births during the
same time interval
1,000
Infant mortality
rate
Number of deaths among children
< 1 year of age during a given
time interval
Number of live births during the
same time interval
1,000
Maternal mortality
rate
Number of deaths assigned to
pregnancy-related causes during
a given time interval
Number of live births during the
same time interval
100,000
Table 3.4 Frequently Used Measures of Mortality

12. Three Levels of Rates
•Crude rates
•Adjusted rates
•Specific rates/ratios

13. Crude Death Rate
•the mortality rate from all causes of
death for a population.
•Does NOT account for differences of
age, sex, etc. in any aspect of death
•Info needed:
total deaths
total population
a given period of time

14. Crude Death Rates
CDR = No. of deaths in one year x 1000
Mid year population
CDR= No. of deaths in one year x 100,000
Mid year population

15. Crude Death Rates
(cont’d)

16. Cause Specific Mortality Rate
SDR = Death due to specific causex
1000/100,000
Mid year population

17. Cause Specific Mortality Rate

18. Specific Death Rates
•For example: Early life mortality measures

19. Age-Specific Death Rate
•An age-specific mortality rate is a mortality rate
limited to a particular age group.
•The numerator is the number of deaths in that
age group; the denominator is the number of
persons in that age group in the population.
•Some specific types of age-specific mortality
rates are neonatal, postneonatal, and infant
mortality rates

20. Specific Death Rates
•For example: infant mortality
Number of deaths among children < 1 year of age, in a given time period x 1000
Number of live births reported during the same time period
•The infant mortality rate is generally calculated on an
annual basis.

21. Specific Death Rates
•Neonatal mortality rate
(cont’d)
•Postneonatal mortality rate

22. Neonatal & Postneonatal Death Rates

23. Specific Death Rates
•Perinatal mortality rates
(cont’d)

24. Sex Specific Mortality Rate
•A sex-specific mortality rate is a mortality
rate among either males or females.
•Both numerator and denominator are
limited to the one sex.

25. Maternal Mortality Rates

26. Maternal Mortality Rates
(cont’d)

27. Adjusted Death Rates
•Allows comparisons by controlling
for differences in some variables
Standardized Mortality Ratio(SMR)
Proportionate Mortality Ratio(PMR)
Specific Mortality Rates
•Does NOT account for differences of
age, sex, etc. in any aspect of death
•Info needed:
total deaths
total population
a given period of time

28. Case Fatality Rate
CFR = Total no. of deaths due to particular disease
x100
Total no. of cases due to the same disease
It represents the Ratioof death to cases
Virulence of organism & killing power of a disease
Useful in acute infectious diseases e.g. cholera,
measles
Time interval is not specified

29. Proportional Mortality rate
(ratio)
•No of deaths due to a particular cause or in a specific age
group per 100 or 1000 deaths”.
a) Proportional mortality of a specific disease =
No. of deaths from the specific disease in a year x 100
Total deaths from all causes in that year
b) Under 5 proportionate mortality rate=
No. of deaths under 5 yrsof age in a given year x 100
Total no. of deaths during the same period

30. Years of Potential Life Lost
•Method for calculating YPLL from a line listing
•Step 1. Decide on end point (65 years, average life
expectancy, or other).
•Step 2. Exclude records of all persons who died
at or after the end point.
•Step 3. For each person who died before the end
point, calculate that person’s YPLL by subtracting
the age at death from the end point.
•YPLL individual = end point − age at death
•Step 3. Sum the individual YPLLs.
•YPLL = ∑ YPLL individual

31. Years of Potential Life Lost (YPLL)
YPLL Rate
Years of potential life lost x 1000
Population under age 65 years

32. Years of Potential Life Lost