<prompt> Denominator of crude death rate is -1000 live birthMid year populationTotal number of deaths in a communityTotal number of case population in community  <response>: Crude death rateIt is the simplest measure of mortality.It is defined as the number of death from all causes per 1000 estimated mid-year population in one year, in a given place.Crude death rate No. of death during the year Mid-year population x 1000Specific death rates When analysis is planned to throw light on etiology, it is essential to use specific death rates.The specified death rate helps identify particular at risk group s for prevention.It also permits comparison between different causes within same population.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.Examples -Specific death rate due to TB No. of deaths due to TB in year Mid year population x 1000Specific death rate for male No. of deaths amongst males Mid year population of males x 1000 