<prompt> Which one of the following is a good index of the severity of an acute disease ?Cause specific death rateCase fatality rateStandardized mortality ratioFive year survival  <response>: Case fatality rate is a proportion and not a rate or ratio.Case fatality rate ratioCFR represents the killing power severity of a disease.CFR Total no. of deaths due to disease Total no. of cases of the same disease x 100 