Systems and methods for consumer price index determination using panel-based and point-of-sale market research data are disclosed. Disclosed example methods to determine a consumer price index include defining a plurality of item strata for use in determining the consumer price index, each item stratum being defined by specifying a plurality of attributes associating items with the item stratum, obtaining pricing information for a plurality of items, at least some of the plurality of items having not been preselected for inclusion in any of the plurality of item strata, determining price differentials for the plurality of item strata, a respective price differential for a respective item stratum being determined by combining the pricing information for a group of items, from the plurality of items, having the specified attributes defining the respective item stratum, and combining the determined price differentials for the plurality of item strata to determine the consumer price index.