The scientific basis for claims of efficacy of nosocomial infection surveillance and control programs was established by the Study on the Efficacy of Nosocomial Infection Control project. Subsequent analyses have demonstrated nosocomial infection prevention and control programs to be not only clinically effective but also cost-effective. Although governmental and professional organizations have developed a wide variety of useful recommendations and guidelines for infection control, and apart from general guidance provided by the Joint Commission on Accreditation of Healthcare Organizations, there are surprisingly few recommendations on infrastructure and essential activities for infection control and epidemiology programs. In April 1996, the Society for Healthcare Epidemiology of America established a consensus panel to develop recommendations for optimal infrastructure and essential activities of infection control and epidemiology programs in hospitals. The following report represents the consensus panel's best assessment of needs for a healthy and effective hospital-based infection control and epidemiology program. The recommendations fall into eight categories: managing critical data and information; setting and recommending policies and procedures; compliance with regulations, guidelines, and accreditation requirements; employee health; direct intervention to prevent transmission of infectious diseases; education and training of healthcare workers; personnel resources; and nonpersonnel resources. The consensus panel used an evidence-based approach and categorized recommendations according to modifications of the scheme developed by the Clinical Affairs Committee of the Infectious Diseases Society of America and the Centers for Disease Control and Prevention's Hospital Infection Control Practices Advisory Committee.

The role of the hospital epidemiologist has changed substantially over the last 30 years as medical care has become more complex. The hospital epidemiologist needs training in methods for sur veillance, prevention, and control of nosocomial infections. The hospital epidemiologist also must know how to apply these methods to other areas, including the epidemiology of noninfectious adverse out-comes of medical care. Training in hospital epidemiology should be a defined part of every infectious disease fellowship training program. Ancillary and additional training is available from several sources.

The first two articles in this series reviewed the reasons for widespread acceptance of surveillence and control methods in hospital infection control programs, and discussed important factors contributing to the successes and failures in applying this approach to noninfectious nosocomial events. The quality assurance program ‘targets of surveillence” identified in these articles are referred to as “quality indicators” by other authors and have been defined as “a quantitative measure that can be used as a guide to monitor and evaluate the quality of important patient care and support service activities.” This article highlights those attributes of quality indicators that should be critiqued prior to implementation in a patient care review environment and discusses methods of improving quality indicator performance with ongoing monitoring and evaluation.

The first article in this series reviewed the type of surveillance currently used by most of the infection surveillance and control programs in acute care hospitals in the United States. Five components were identified as critical to the widespread acceptance and continuing success of this surveillance methodology: targeting of events (diseases); early development of standardized definitions; wide acceptance of the criteria for these definitions; advocacy, leadership and education in methodology; and a high level of effectiveness in program practice. Using the framework of these key components, this article will discuss the potential for the application of similar methodology to noninfectious nosocomial adverse events and explore some current successes and problems associated with surveillance for such events.

This review of the use of surveillance by infection control practitioners (ICPs) in nosocomial infection control programs has identified key components that have led to and supported its continued application and success. These include:

◾ Surveillance targeting of events (diseases);

◾ Early development of standardized definitions;

◾ Wide acceptance of these criteria;

◾ Advocacy, leadership and education of methodology and;

◾ A high level of effectiveness in program practice.

The cross-sectional study, also called the prevalence survey, is one of the most popular epidemiologic methods. It has been employed in up to one-third of published studies. This survey method has two primary applications: describing population characteristics and analyzing potential etiologic agents or risk tactors for diseases or other population attributes. Studies of the prevalence of rheumatoid arthritis and the association between smoking and chronic bronchitis are two examples of the cross-sectional method applied at the population-based level.

Inpatient hospital care consumes more than 30% of health insurance dollars regardless of the reimbursement mechanism, be it standarti fee-for-service, preferred provider organization (PPO), or health maintenance organization (HMO). It is understandable that reducing these costs has become the highest priority of health care purchasers, and that utilization review and management, the process of evaluating and attempting to reduce the cost of medical practice, has become a major growth industry with providers and purchasers of health care.

As the consumers and regulators of health care have become more concerned with quality of delivered services, interest has focused on hospital- and physician-specific mortality rates as an index of quality. Mortality rates have several characteristics that promote their use as a performance indicator. The numerator, death, is generally (but perhaps incorrectly) accepted as an adverse outcome of health care. Death is thought to be easily measured, and is recorded in several locations, including the medical record abstract and death certificates, where the information is accessible without provider consent. The denominator, persons or patients, is also available from several public sources. The desirability of mortality data is further enhanced by the wide variety of statistical methods to manipulate and compare rates and proportions. The conceptual validity of mortality rates as reflecting quality is supported by a long tradition of using mortality rates at the “macro” level to compare the quality of national health care delivery systems (eg, infant mortality rates) and at the “micro” level to compare the outcome of different therapies (eg, thrombolytics for acute myocardial infarction). However, despite face validity, ease of measurement, and widespread acceptance in other areas, hospital-specific mortality rates, as calculated from current data sources, have a variety of potential problems.This article will explore the clinical, administrative, and information-based difficulties in using mortality rates as an indicator of the quality of medical care delivered by specific hospitals or physicians.

As the consumers and regulators of health care have become more concerned with quality of delivered services, interest has focused on hospital- and physician-specific mortality rates as an index of quality. Mortality rates have several characteristics that promote their use as a performance indicator. The numerator, death, is generally (but perhaps incorrectly) accepted as an adverse outcome of health care. Death is thought to be easily measured, and is recorded in several locations, including the medical record abstract and death certificates, where the information is accessible without provider consent. The denominator, persons or patients, is also available from several public sources. The desirability of mortality data is further enhanced by the wide variety of statistical methods to manipulate and compare rates and proportions. The conceptual validity of mortality rates as reflecting quality is supported by a long tradition of using mortality rates at the “macro” level to compare the quality of national health care delivery systems (eg, infant mortality rates) and at the “micro” level to compare the outcome of different therapies (eg, thrombolytics for acute myocardial infarction). However, despite face validity, ease of measurement, and widespread acceptance in other areas, hospital-specific mortality rates, as calculated from current data sources, have a variety of potential problems.This article will explore the clinical, administrative, and information-based difficulties in using mortality rates as an indicator of the quality of medical care delivered by specific hospitals or physicians.

Hospitals, insurance companies, and federal and state governments are increasingly concerned about reducing patient cost expenditures while maintaining high quality patient care. One method of reducing expenditures has been to tie hospital reimbursement with a prospective payment system based on diagnosis-related groups (DRGs). However, reimbursement under the DRG system is not acceptable for all patients in all hospitals because it is neither an accurate predictor of costs nor of clinical outcome. This deficiency poses significant problems for hospitals because DRGs are used nationwide as the prospective payment system for inpatients covered by Medicare. Several case-mix adjusters have been proposed to modify DRGs to improve their accuracy in predicting costs and outcome. We reviewed five of the most widely available indices: Acute Physiologic and Chronic Health Evaluation (APACHE II), Coded Disease Staging, Computerized Severity Index (CSI), Medical Illness Severity Group System (MEDISGROUPS), and Patient Management Categories (PMC). Recommendations for the use of a single case-mix adjuster cannot be made at this time because all indices have not been compared in sufficiently diverse settings and because some are better predictors of costs while others are better predictors of clinical outcome. Hospital epidemiologists and other infection control practitioners should be informed about these indices and their potential applications as they expand their role beyond infection control problems to issues concerning cost containment, quality assurance, and reimbursement.

Hospitals, insurance companies, and federal and state governments are increasingly concerned about reducing patient cost expenditures while maintaining high quality patient care. One method of reducing expenditures has been to tie hospital reimbursement with a prospective payment system based on diagnosis-related groups (DRGs). However, reimbursement under the DRG system is not acceptable for all patients in all hospitals because it is neither an accurate predictor of costs nor of clinical outcome. This deficiency poses significant problems for hospitals because DRGs are used nationwide as the prospective payment system for inpatients covered by Medicare. Several case-mix adjusters have been proposed to modify DRGs to improve their accuracy in predicting costs and outcome. We reviewed five of the most widely available indices: Acute Physiologic and Chronic Health Evaluation (APACHE II), Coded Disease Staging, Computerized Severity Index (CSI), Medical Illness Severity Group System (MEDISGROUPS), and Patient Management Categories (PMC). Recommendations for the use of a single case-mix adjuster cannot be made at this time because all indices have not been compared in sufficiently diverse settings and because some are better predictors of costs while others are better predictors of clinical outcome. Hospital epidemiologists and other infection control practitioners should be informed about these indices and their potential applications as they expand their role beyond infection control problems to issues concerning cost containment, quality assurance, and reimbursement.

The need for accurate data concerning nosocomial infections has long been appreciated by infection control practitioners. Several major changes in the health delivery environment have highlighted for other care givers and managers the importance of, and indeed necessity of high-quality clinical and financial hospital information. Since 1983, the Medicare prospective payment system (PPS) has used the medical record discharge abstract as the hospital bill. This has created a need for more detailed clinical information in hospital information systems. In several states, all third-party reimbursers are using PPS variants, further strengthening this incentive. The “Agenda for Change” of the Joint Commission on Accreditation of Healthcare Organizations has created further pressure on hospitals to acquire information concerning the quality of care at their own facility, as well as comparative statistics from other facilities. Although trade journals extol the virtues of “good data sets,” and much academic study has been given to individual facets of data processing and handling, the practical aspects of hospital information opportunities and problems have been largely ignored. The purpose of this article is to discuss the nature of hospital data; to detail available sources of national, regional, and local hospital statistics; to delineate potential quality problems common to many types of hospital information; and to discuss difficulties with and solutions to some hospital data application problems.

As with all human endeavors, medical care in any setting has observable and occult benefits and risks. The methods of study of these facets of medical care have become known as “clinical epidmiology.”

This article is the introduction to a new series entitled “Topics in Clinical Epidemiology.” The authors are practicing clinicians, one as director of the Quality Assurance department and the other as director of the Hospital Epidemiology department, both at a large tertiary teaching hospital. The series will attempt, in the fashion of the old shoe leather epidemiologist, to reflect those problems and interactions which are the realities of our current practice milieu and experience. That this collection of manuscripts will be presented in an infection control periodical reflects the journal's and the authors' perspective that the same epidemiological techniques that have made infection control clinically successful and cost-effective can be used to reduce noninfectious hazards of medical care, and to enhance the diagnostic and therapeutic benefits of modern medical management.