We found a matchYour institution may have access to this item. Find your institution then sign in to continue.TitleInfluenza vaccine effectiveness in the elderly based on administrative databases: change in immunization habit as a marker for bias.AuthorsHottes TS; Skowronski DM; Hiebert B; Janjua NZ; Roos LL; Van Caeseele P; Law BJ; De Serres GPublicationPloS one, 2011, Vol 6, Issue 7, pe22618ISSN1932-6203Publication typearticleDOI10.1371/journal.pone.0022618