The terrorist attacks of September 11, 2001 prompted a wave of epidemiologic research, as the chapters in this edited volume illustrate. The three investigators, who have summarized their field work and selected findings in the first section of this volume, deserve much praise for their initiative in launching and completing their studies in the midst of local and national upheaval (Galea et al., this volume; Hoven et al., this volume; Silver et al., this volume). The three epidemiologic studies implemented field procedures, designed to produce data on the psychological responses to the 9/11 attacks that are representative of the targeted populations. These include New York City (NYC) public schoolchildren, adult residents of the NYC metropolitan area and all American adults. These investigators applied welltested state-of-the-art survey technologies to assure timeliness and efficiency. Data produced in these studies have been presented in multiple publications in leading medical journals and more publications are sure to follow. The chapters included herein focus primarily on the conduct of the research, organizational support, design options that were considered and the rationale for the choices that were made. In giving these accounts, the chapters contribute an interesting and instructive perspective that is often hidden from view. The more difficult goal of outlining lessons that could influence policy remains elusive. Recommendations for prevention programs that are not based on rigorous evaluation would be unwarranted.

Perhaps because of the enormity of the terrorist attacks or because of the upsurge in patriotic sentiment occurring in their wake, critical discussion of the conceptual underpinnings and implications, or even the methodological aspects of this work, has been largely absent.