of processes, that is, statistical thinking. Decisions are based on data rather than intuition, so information systems are built and graphical tools are used to monitor critical processes and track the effects of alterations in the delivery of a service or the production of a product

Using these tools, workers are empowered to continually adjust the process and make consistent and persistent improvements in both process and outcomes. Gradual improvement in all aspects of life, but particularly the quality of the environment, process, and products of work, is embodied in the Japanese word kaizen (ky'zen) (Imai, 1986). A commitment to kaizen requires a careful understanding of processes, systems, and consumers and the application of strategies and tools to the production and delivery of high-quality products and services. The focus on long-term gradual improvement by using scientific methods and by paying attention to consumer needs characterizes true quality improvement orientations.

Application of quality improvement methods has expanded substantially in health care settings. An annual review of the U.S. health care system reported that 94 percent of hospital chief executives believed that quality improvement programs would enhance efficiencies and reduce costs; 61 percent anticipated increased market share because of quality improvement initiatives (Business and Health Magazine, 1993). Increasingly, accreditation agencies and purchasers expect organizations to have formal quality improvement programs and assess the quality improvement processes as part of their review of a health care organizations (e.g., AMBHA, 1995; CARF, 1996; Digital Equipment Corporation, 1995; NCQA, 1996; URAC, 1996). Similarly, the federal Health Care Financing Administration is responsible for monitoring the quality of services for Medicare recipients and is supporting a quality improvement initiative that emphasizes continuous quality improvement methods, makes information available to the public, is consistent with state and private certification and accreditation programs, and employs multiple measures of quality and performance (GAO, 1996).

Improvements in patient care and outcomes are the ultimate result of quality improvement technology within health care settings. Applications are inhibited, however, because of the variable presentation of illnesses, variations in practice patterns, the hierarchical structure of patient care, and the complexity of hospitals and managed care programs. The “gold standard” for effectiveness continues to be randomized clinical trials, which are prohibitively expensive.

It is therefore noteworthy, for example, that the Northern New England Cardiovascular Disease Study Group applied quality improvement techniques and documented a significant reduction in hospital mortality associated with coronary artery bypass graft surgery in a multi-institutional regional environment (O'Connor et al., 1996). Clinicians, administrators, and researchers from the five hospitals in Vermont, New Hampshire, and Maine where coronary artery bypass