The Health of Complex Human Populations
Health care and public health are finding common-but conflicted-ground in population health. Current discussions in the two fields are collecting a large and growing set of tools, but with little clarity about which are appropriate for exactly what kind of work. Furthermore, neither field provides a clear explanation about how to manage this work within the field, including budgets, job descriptions, and evaluation methods, etc. that distinguish between good and better, efficient, effective or
... ot. The following article offers four linked domains of thought and practice that together constitute a bridge from where we are to where we want to be-healthier people and institutions-by using the idea of the Leading Causes of Life as the supporting paradigm. (1) Public Health The 1988 Institute of Medicine (IOM) report The Future of Public Health (IOM, 1988) confronted the disarray of the public health field (including governmental public health agencies) frankly, and set underway a quarter century of laborious reforms in its structure, training, and budget priorities. Some of these reforms continue, most recently in the form of the effort to accredit local and state public health departments. This movement within public health accelerated the conceptualization of public health as a field of conscious transformation of interlinked community systems. This conceptualization of a movement in public health implies a body of competencies suited to transforming, not just maintaining, those systems (Wright, 2000) , which is reflected in the emergence of nearly two dozen state level leadership institutes aligned with those bold future-oriented goals. The 1988 report was revisited and updated in the 2003 report The Future of the Public's Health in the 21 st Century (IOM, 2003) . This underscored a key insight, which was that public health as a field is still new and under construction. (2) Quality Health Care Another IOM publication, Crossing the Quality Chasm: A New Health System for the 21st Century (IOM, 2001), chaired by William Richardson, with the strong influence of Donald Berwick and others, played a similar role within health care organizations, laying bare the radical gap between optimal science and actual organization of delivery of that science into patients' lives. The report defined quality as six aims: safe, timely, effective, equitable, efficient, and patient-centered (STEEEP). This accelerated the large body of work of process improvement most visible in the community of "thinker-doers" of the Institute of Healthcare Improvement (IHI). Throngs of others echoed their promise to advance a compact (and easier to remember) "Triple Aim Initiative." 2 (3) Health Care Business Meanwhile, inside the management of health care organizations, the work of Michael Porter drew a compelling map of the future, mainly with sharply focused service lines, organizational consolidation and cost-driven bundles 3 of care offering greater value for payers (and presumably patients). His book with Elizabeth Teisberg on Redefining Healthcare (Porter and Teisberg, 2006) makes tactical operational recommendations addressed to those managing health care businesses. Porter and Teisberg insist that systems act like systems, not just a collection of facilities. Porter and Teisberg offer great hope for the role of rationality, discipline and, of course, financial incentive. Within a system or within a referral region, volume should aggregate to the sites capable of the highest quality-those specialized enough to have high volume-and thus the highest economic efficiencies. In practice this means, for instance, closing obstetrics or cardiac surgery units at small hospitals, driving the specialized care to a hub or even to a competitor. In actual institutions those decisions are excruciatingly painful. Crossing the Quality Chasm contained a whole chapter on health care organizations as complex adaptive systems with quality as an emergent "system property" (IOM, 2001) .