“…Although some respondents had experience with older, less effective versions of these vaccines, the improved "next generation" cholera or typhoid vaccines were generally unavailable in these countries except in limited trials designed to evaluate the vaccines' protective effectiveness, during which they were distributed free of charge (Jeuland et al 2009c). Because of this unavailability of "next generation" vaccines, we relied on stated preference techniques to measure household demand (Canh et al 2006, Lucas et al 2007, Islam et al 2008, Kim et al 2008. This information was then used to evaluate the economic attractiveness of investments in these vaccines using both benefit-cost and cost-effectiveness techniques , Cook et al 2009b, Jeuland et al 2009b.…”