About direct standardization all are true except ?

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.