Measures of Mortality Mortality in Different Populations Mortality

Measures of Mortality & Mortality in Different Populations

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

Mortality Table

Selected Mortality Rates

Maternal( )ﺍﻷﻤﻬﺎﺕ Mortality

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

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

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

Mortality • Deaths; describes death; related issues • Graunt ü 1600 s – Bills( )ﺷﻬﺎﺩﺓ– ﻋﻤﻠﺔ ﻭﺭﻗﻴﺔ of Mortality • Farr (1807 -1883) ü Registrar general; vital statistics üCauses üRegistration

Types of Mortality Rates/Ratio • • • • annual death rate crude death rates infant mortality rates (ratio) neonatal mortality rates postneonatal mortality rates perinatal mortality rates fetal death ratios 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

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

Annual Death Rates • “General” (crude) mortality rate ü a population group exposed to risk of death ü a time period • Crude Mortality Rate = # of deaths occurring in that population during that period of time

Crude Death Rates • Does NOT account for differences of age, sex, etc. in any aspect of death • Info needed: ü total deaths ü total population ü a given period of time

Crude Death Rates (cont’d)

Cause Specific Mortality Rate

Cause Specific Mortality Rate

Case Fatality Rate

Specific Death Rates • For example: Early life mortality measures

Specific Death Rates • For example: infant mortality

Infant Death Rates in the U. S.

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

Neonatal & Postneonatal Death Rates

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

Specific Death Rates(cont’d) • Fetal death rate

Maternal Mortality Rates

Maternal Mortality Rates(cont’d)

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

Adjusted Death Rates Age Adjusted Rates • Direct Method

Adjusted Death Rates Age Adjusted Rates • Direct Method (cont’d)

Adjusted Death Rates Age Adjusted Rates • Direct Method (cont’d)

Adjusted Death Rates Age Adjusted Rates • Indirect Method ü Standard Mortality Ratio (cont’d)

Standardized Mortality Ratio (SMR)

Standardized Mortality Ratio (SMR)

Standardized Mortality Ratio (SMR)

Specific Mortality Rates • Age specific mortality rate

Age-Specific Mortality Rates

Other Issues Related to Mortality • Mortality Cross-over ü Death of a subject that started in one group but “crossed over” to another group during course of study • Mortality Time Trends • Years of Potential Life Lost (YPLL) üYPLL Rate

Years of Potential Life Lost