Definition: Dual records system
A method of collecting vital statistics data, mainly births and deaths, through household demographic sample surveys on a continuous basis. It is a special case of the follow-up survey method, which allows for the validation of information from two independent reporting sources, both based on survey techniques. Two independent records are collected on each vital event occurring in the selected sample areas. These two records are established by a continuous registration and a retrospective survey. The events reported in the two systems are then matched and the unmatched events are field-verified to ensure that the events belong to the sample area and have occurred within the reference period.
United Nations, "Handbook on Training in Civil Registration and Vital Statistics Systems", Studies in Methods, Series F, No. 84, New York, 2002