Utilization management of acute care services : evaluation of the SWITCH index system

In recent years, concern about the rising costs of health care has prompted the development of programs aimed at reducing utilization of hospital services and facilities while maintaining an acceptable standard of care. One of the major strategies that has emerged in the effort to accomplish these dual objectives, is utilization management. Although there are a number of different approaches, the primary aim of all utilization management programs is to identify and eliminate unnecessary and inappropriate hospital use. To date, most of the utilization research and program development has taken place in the United States. To a great extent, this effort has focussed on the development and use of norms for utilization based on a breakdown of length of stay data by diagnostic-related groups (DRG's). Canadian interest in this type of approach is reflected in the recent development of data bases defined by case-mix groups (CMG's). However, while continued efforts are being made to refine these schemes, they have been vulnerable to the criticism that they do not provide adequately objective criteria for establishing what constitutes appropriate patterns of hospital use. In addition, because they are based on statistically derived norms, they have been criticized as lacking sufficient clinical relevance to encourage physician support. Since hospital utilization is largely determined by the medical staff, utilization management programs that fail to obtain physician support are unlikely to succeed. An alternative approach, which appears to be gaining in popularity, involves the formulation of criteria which can be used to determine what constitutes appropriate and necessary hospital use. Essentially, it is argued that by directly identifying the source and nature of misutilization, it should be possible to develop more effective strategies for the resolution of identified problems. The American Appropriateness Evaluation Protocol designed by Gertman & Restuccia (1981) is one of the earliest and most highly tested examples of a criterion-based system. In Canada, interest in this type of approach is more recent and, consequently, little attention has as yet been focussed on the development and use of clinical criteria in utilization review and management. One exception, however, is the SWITCH Index System. This system, which was developed and implemented in 1984 by the Peace Arch District Hospital (White Rock, B.C.), makes a direct attempt to identify and eliminate days of hospital stay during which no appropriate acute care services are being provided. The criteria used in this system are classified under the headings Signs, Wind, Intramuscular Therapy, Tubes, Consultant, and Hospice. Patients are considered to be appropriately placed in the hospital if, on any given day, at least one of the specified criteria are met. Otherwise they are classified as Off-Index and action is taken to identify the source of the problem and to initiate corrective action. Since a major objective of the SWITCH system is to identify and eliminate inappropriate use, an observable outcome, if the program is successful, should be a reduction in length of stay. The present study investigated this hypothesis by comparing pre- and post- intervention length of stay trends at the Peace Arch District Hospital. In addition, to take into account any general secular trends in length of stay over time, the Peace Arch length of stay was compared to the length of stay observed for a control group of three peer-group member hospitals. Although data covering the four year period 1982 to 1985, indicated that the length of stay at the Peace Arch District Hospital had been decreasing over time, no component of this general decline could be attributed to the SWITCH Index System. Time series regression analyses failed to detect changes in either the slope or the height of the estimated response curve. However, limitations in the study design do not permit any conclusions regarding the potential effectiveness of this system. Characteristics specific to the Peace Arch District Hospital may have prevented the detection of an effect. In addition, because it is likely that there would be a lag between when the program was implemented and when it might be expected to effect a reduction in length of stay, the follow-up period of eleven months may have been too short for the determination of the program's effectiveness.Medicine, Faculty ofPopulation and Public Health (SPPH), School ofGraduat