Simplest measure of mortality -
Ans. is 'a' i.e., Crude death rate o The simplest measure of mortality is the crude death rate.MEASUREMENT OF MORTALITYo Most epidemiological studies begin with mortality data.o The commonly used measures for mortality are :-Crude death rate iii) Proportional mortality1 rate v) Case fatality rate Specific death rate iv) Survival rate vi) Standardized or adjusted ratesCrude death rateo It is the simplest measure of mortality'.o It is defined as "the number of death (from all causes) per 1000 estimated mid-year population in one year, in a given place ",Specific death rateso When analysis is planned to throw light on etiology, it is essential to use specific death rates,o The specified death rate helps identify particular 'at risk' group (s) for prevention.o It also permits comparison between different causes within same population,o The specific death rates may be -Cause or disease specific, e.g. TB, cancer, accident.Related to specific groups - e.g. age specific, sex specific,o Examples - Proportional mortality rate (ratio)o Proportional mortality rate measures the proportion of total death due to specific cause or proportion of deaths in a particular age group.o It is defined as "number of deaths due to a particular cause (or in specific age group) per 100 total deathso It is the ' simplest measure of estimating the burden of disears' in the community',o It is a useful ''health Status indicatorindicates magnitude of preventable mortality,o It is used when population data is not available.o It does not indicate the risk of members of population contracting or dying from the disease. Survival rateo It is the proportion of survivors in a group (e.g. of patients) studied and followed over a period of time,o It is a method of describing prognosis in certain disease conditions,o Survival experience can be used as a yardstick for the assessment of standard of therapy.o Survival rates have received special attention in cancer studies.o Survival period is usually reckoned from the date of diagnosis or start of the treatment.o Case fatality' rate is a proportion and not a rate or ratio (will be explained in details in respective questions).Case fatality rate ( ratio)o CFR represents the killing power (severity) of a disease.Adjusted or standardized rateso Standardization (or adjustment) of rates is used to unable the valid comparison of groups that differ regarding an important health determinant (most commonly age).o For example, if we want to compare the death rates of two different populations with different age composition, the crude death rate is not right yardstick because rates are only comparable if the populations upon which they are based are comparable.o To remove this confounding effect of different age structure, adjustment or standardization is done.o Two major approaches to standardization have been usedDirect standardizationIndirect standardization
Crude death rate
Case fatality rate
Proportional mortality rate
Specific death rate
Epidemiology