<prompt> Sample registration survey is conducted every?6 months1 year2 years10 years  <response>: ANSWER: A 6 monthsREF: Park 22nd ed page 785There are four major sources of vital statistics in India, namely;The Sample Registration System SRSThe Civil Registration System CRSIndirect estimates from the decennial censusIndirect estimates from the National Family Health Surveys NFHS.The first three are operated by the Registrar General India RGI working under the Ministry of Home Affairs. The NFHS is organised by the International Institute of Population Sciences IIPS, working under the Ministry of Health and Family Welfare.Sample registration system:Initiated in 1960s to provide birth and death at state and national levelIts a dual record system consisting of enumeration of birth and death continuously and an independent survey by investigator supervisor every 6 months 