About direct standardization all are true except ?
Age specific death rate is not needed
A standard population is needed
Population should be comparable
Two populations are compared
Ans. is 'a' i.e., Age specific death rate is not needed Direct standardization Direct standardization is used when the study population is large enough that age specific rates within the population are stable. o Direct standardization is commonly used in repos of vital stastics (e.g., moality) or disease incidence trend (e.g. cancer incidence). o A standard population (reference population) is selected for which the numbers in each age and sex group are known. o Next, age-specific rates of study population (population whose crude death rate is to be adjusted or standardized) are computed. o Then, these age specific rates of study population are applied to standard population (by multiplying these rates by the number of people in that age group in the study population). o These expected rates are summed and divided by the total population size of standard population to yield the directly standardized rates.