Commentary

Abstract

It was well beyond my expectations when I heard from Professor Ames that our meta-analysis paper (Han et al., 2000) was among the top-cited papers in International Psychogeriatrics. As an expression of my gratitude to the editor for the invitation and to the audience of this paper, I would like to offer this informal discussion on the background of the paper and extend a few ideas that were not conveyed fully at the time, due either to insufficient knowledge or unavailability of relevant data or methodologies.