Showing papers in "Journal of Medical Systems in 1978"

A delay-scheduling model for patients using a walk-in clinic.

Abstract: Clinics receiving unscheduled visits experience wide fluctuations in the number of patients present at any one time, due to random arrival of patients and variations in the time needed for the evaluation and treatment. This can cause periods of congestion and long patient waiting times. Using a flexible technique for “delay scheduling,” a study was conducted to determine the most efficient use of limited physician resources in the management of patients using a walk-in clinic. Delay scheduling makes it possible to shift work load from periods of high congestion to other times without compromising the walk-in nature of the clinic. A computer simulation model was used to evaluate the clinic performance with different physician staffing patterns and different rules for delay scheduling. The model was validated using actual data from the walk-in clinic and the results implemented. The delay scheduling and staffing changes resulted in reduction of manpower by 10% while significantly reducing the clinicaccountable waiting time.

Unlimited volumes of laboratory data: a confusing and diagnostically deceptive product of modern technology.

Abstract: The large volumes of laboratory data currently available in clinical practice can lead to erroneous conclusions. Our current statistical interpretation of these data is univariate (one variable at a time) and often not age-and sex-corrected. Using an optimal technique of multivariate analysis, a SMAC® profile of 19 tests performed on normal subjects resulted in over a 500% improvement in defining the reference range. Using physiologic subsets of the SMAC profile for patients, improvements in interpretation of between 100% and 300% are possible. Results indicate a serious clinical problem that will require modification of laboratory reports using modern technology as an adjunct for diagnostic medicine.

Planning a dental practice with a management game

Abstract: This paper describes how a dentist can use a new management tool, a computerized dental practice management game, to plan his or her own practice. After reviewing factors to be considered in planning a dental practice, we briefly describe the game with special emphasis on what it can and cannot do. After identifying the information required to make such an exercise useful in planning a specific practice, the paper gives an example that shows how the game can be so used.

Establishing a multivariate clinical laboratory data base.

Abstract: A regional or hospital-based “reference” value study is well within the range of every clinical laboratory. A program is described that samples one to two “health” subjects each working day under tightly controlled conditions. Sixty-seven variables are tested simultaneously to provide univariate age and sex ranges, and variance/covariance matrices from which associated correlation coefficients are obtained. This ongoing “reference” value program offers essential information for both univariate and multivariate interpretations along with validation and quality control for certain methods within the clinical laboratory.

A guideline matrix for technological system evaluation

Abstract: It is often necessary to scientifically evaluate a complex technological system. Such an evaluation usually requires determination by the system's costs, its effectiveness in achieving the system's objectives, its efficiency in the use of costly resources, its cost-effectiveness as compared to other alternatives, and the benefits gained by its expenditures. A matrix is presented as a suggested guideline for a comprehensive evaluation of a technological system.

A multivariate data reduction system

Abstract: The problem of predictive diagnosis based on laboratory data is approached from a mathematical standpoint. A descriptive system is introduced which examines the current information about a clinical problem and identifies best predictors of the problem. Algorithms are described for the assessment of current diagnostic ability, the evaluation of new laboratory tests, and the identification of patients to study for the development of new procedures. The laboratory approach to the predictive diagnosis of iron deficiency is chosen as an example of the system.

The Miami Heart Institute information system.

Abstract: The Miami Heart Institute automation project, conceived as a comprehensive unified hospital information system, has been in continuous development since 1969. As of February 1978, the system supports medical services and laboratories as well as teaching, financial, administrative, and research applications through approximately 100 remote terminals. It is controlled by a single operating system serving interrelated data bases and is available to its users practically 24 hours a day, 7 days a week. The information system transfers data to and from dedicated mini- and microcomputer systems and incorporates digital and analog instrumentation interfaces that include physiologic signal-processing capabilities. Acceptance by user departments ranges from good to excellent, whereas acceptance by the private attending staff at large has been only fair. This report presents a general overview of several major subsystems and discusses advantages and shortcomings of the project.

Nonparametric detection scheme for myocardial infarction

Abstract: Bernstein et al.1 have suggested a method for the detection of myocardial infarction using the combined measurement of serum LD activity and inhibition of LD by pyruvate (which depends on the amount of LD from damaged myocardium). This is another in the growing number of applications of discriminant analysis in medical diagnosis. As is often the case, the true underlying distribution of the data is not known. In this case, in particular, an attempt is made at defining the distribution to more accurately assess those patients among whom the diagnosis of myocardial infarction is suspect but is not clearly identified. Tsokos and Welch2 have shown that discriminant procedures based on incorrect assumptions of the underlying distribution led to substantially higher error rates. In this paper, we consider the application of a nonparametric probability density estimator recently developed by David W. Scott.3 This leads to a rather accurate discriminant procedure that is applicable to many other types of data.

A problem-oriented approach to medical information systems: an application in a primary care group practice.

Abstract: A relatively simple computer-based information system developed for a primary care group practice at the San Francisco Veterans Administration Hospital contributes to the management of the practice, to improvement of medical care for patients within the group, and to research studies on resource utilization in the management of chronic diseases and the evaluation of care of chronically ill patients. Preliminary results from the use of the information system are encouraging and demonstrate that much may be achieved by information systems that do not attempt to computerize the entire medical record.

An input-output model for resources planning in a medical care system.

Abstract: As medical care delivery systems grow in complexity, the understanding of interaction between entities within the system becomes a key aspect in resource planning. The model presented in this paper is geared to aiding resource planning both at the community or regional level and at the medical facility level. At the regional level the problem is related to the elimination of duplication and the sharing of services. At the medical facility level the concern is the balancing of the supply and demand of services among the departments. The framework of the model is a directed graph with nodes representing the service entities and branches representing the interrelationships. At the regional level, entities are hospitals, clinics, and centralized supportive units, such as the data center or the central laboratory. At the medical center level, entities are generally departments within the facility. An iterative procedure is used to simulate the propagation effect of a change on all entities. The model at the medical center level, as implemented in a minicomputer system was applied to a real problem. The results strongly correlated with another, independent study.

A survey of financial planning models for health care organizations.

Abstract: This paper describes “what if?” financial planning models developed for health care administrators and financial managers to study and evaluate the economic impact of changes in a health care organization's charge structure, operating policies, reimbursement plans, and services and resources. Models for inpatient and outpatient care systems are presented. The models are described in terms of input, output, and application. An assessment of the state of the art of financial planning and prospects for the future of what if? models are given.

Quality considerations in medical records abstracting systems.

Abstract: Health Information Systems utilizing computerized medical records abstracting services are widely applied to clinical research, utilization review, health statistics, and similar programs. The utility of such systems is determined primarily by the accuracy of stored abstracts. Even very low per-character error rates can result in a relatively high proportion of abstracts in error. Application of quality control procedures and purposeful design of error identification systems is essential for establishing face validity. Acceptance sampling with comparison of abstracts to medical records can be employed to assure content validity.

Song of the sirens

Abstract: There are few who, at one time or another, have not read the Odyssey and followed the travels and various adventures of Odysseus (Ulysses). It will be recalled that among his narrow escapes, Ulysses passed the island of the Sirens, located near the west coast of Italy. If it were not for his quick thinking (he plugged his crew's ears and tied himself to the ship's mast), the songs of the island inhabitants would have lured Ulysses and his ships to an untimely (and permanent) stop at the island. Modern-day Ulysses (commonly referred to as consumers) are constantly lured by Sirens, whose call issues forth from pages of advertising. Recently added to these various \"calls\" are advertisements for medical computer systems directed toward the potential \"small system\" physician user. As ear plugs, rope, and masts are sometimes unavailable, there is virtue in examining these islands of song to aid in distinguishing the rocky shoals from the safe harbors.

A systems approach to planning large-scale, integrated health care facilities

Abstract: This paper presents an overview of a systems approach being implemented within the Kaiser-Permanente Medical Care Program (KPMCP) for the planning of large-scale, integrated health care facilities. This approach was motivated by the increasing change and complexity of factors, both external and internal to KPMCP, that now require more systematic treatment and that before were handled by more intuitive approaches. Among others, these factors include dealing with increasing regulation from government agencies and accommodating the active participation of knowledgeable personnel to ensure the continuation of a progressive and innovative system. Described within, along with more general issues, are various computer models, based upon Kaiser concepts and data that have been developed to facilitate the effective allocation of resources.

A quality of care evaluation measure for emergency medical service systems.

Abstract: This paper presents the development and validation of an emergency medical service (EMS) systems quality of care evaluation measure. The System Input Severity Measure consists of a et of single and multiple injury survival rates that would be expected to occur in an EMS system classified as providing “baseline” advanced life support services. These expected survival rates were developed by a nationwide panel of emergency medicine experts through the use of the Delphi group opinion surveying technique. Validation of the System Input Severity Measure was a twofold process. First, reliability of the results of the Delphi surveying process was validated by comparing the resultant expected survival rates with Illinois Trauma Registry data. Second, the applicability of the measure was validated using data collected in EMS systems generally recognized to be providing exceptional (either superior or inferior) emergency patient care. It was recognized that the development of a comprehensive, largescale System Input Severity Measure through the use of the Delphi technique alone is impractical. Consequently, a functional relationship between single and multiple injury survival rates was also developed. It appeared that when employed in conjunction with data developed from the Delphi technique, such an approach would make practicable the development of a comprehensive System Input Severity Measure.

On-line storage, retrieval, and evaluation of long-term electrocardiographic monitoring data.

Abstract: A set of on-line computer programs has been designed and implemented for the acquisition and long-term storage, retrieval, and evaluation of Holter monitoring data. The physician interpreting Holter tapes enters his findings in the computer system using an on-line remote terminal located in the heart station. The programs are available practically around the clock and allow reviewing of individual cases, preparation of printed reports, and fast evaluation of the presence or absence of a number of common findings in the entire data base. Approximately 800 cases have been entered since the initiation of this project in early 1977.

Computerized assessment of diabetes patient education

Abstract: A computerized health education assessment program, designed to capture data on patient's knowledge of diabetes self-care, is described. Feedback to the patient and professional is provided by a computer-generated educational prescription. The data base accumulated on individual patient's responses to test questions can be used to evaluate various aspects of the teaching program. By linking pooled assessment data with clinical parameters, regression studies can be carried out to ascertain the impact the training program has had both on compliance and in preventing or reducing the incidence of complications.

The acceptability of computer applications to group practices.

Abstract: Of the 72 identified group practices in a midwest urban environment, 39 were found to use computers. The practices had been influenced strongly by vendors in their selection of an automated system or service, and had usually spent less than a work-month analyzing their needs and reviewing alternate ways in which those needs could be met. Ninety-seven percent of the practices had some financial applications and 64% had administrative applications, but only 2.5% had medical applications. For half the practices at least 2 months elapsed from the time the automated applications were put into operation until they were considered to be integrated into the office routine. Advantages experienced by at least a third of the practices using computers were that the work was done faster, information was more readily available, and costs were reduced. The most common disadvantage was inflexibility. Most (89%) of the practices believed that automation was preferable to their previous manual system.

Guidelines for use access to compuuterized medical records

Abstract: Computerization of the medical record allows the unique capability to provide differential access to various components of the record by users outsid of the immediate provider/patient health care setting Guidelines for designers, programmers, and users of computerizeid medical records have been defined in order to clarify which data elements or categories are appropriate for communication to various parties involved in utilizing patients information.

A component approach to health systems design

Abstract: This research concerns the development of a strategy that will assist in the design of health systems by making decision-makers in the health field aware of the best available methods for performing the functions required by their organizations. A procedure for identifying, evaluating, and documenting cost-effective health systems components is presented. Use of the procedure is illustrated through an application to the billing function in group medical practices. An evaluation model is developed using psychometric scaling techniques and is validated by comparing its performance to the independent evaluations of expert panelists.

An illustration of the technique of canonical analysis

Abstract: The use of a multivariate statistical technique, canonical analysis, for the assignment of patients to diagnostic categories is presented. The classification of thyroid status using clinical findings is investigated to exemplify the application of the technique. Emphasis is placed on the stages in the data analysis that are generic in examining any set of medical data for the purpose of automatically classifying patients.

Design and construction of a microdensitometer computer interface

Abstract: This project consisted in modifying the output of a scanning microdensitometer so that a computer could accept and process the (optical) density versus position information gathered from radiographic film. The system functions were separated into two parts: the actual datagathering process, which required real-time response, and the calculation associated with the data. Separation of functions allowed a less expensive system overall while still preserving flexibility. For the real-time control computer, a relatively slow microprocessor-based system (Motorola MC6800) was chosen. The microdensitometer was modified to allow computer control of the scan. The density versus position information was digitized using optical shaft encoders. Cassette tape was used as a mass-storage medium for complete scans. Using an acoustic coupler, the microprocessor was cofigured to transmit accumulated data to a timeshare system for analysis. The results were retransmitted and displayed on a TV screen or printed on a line printer or teletype. The total cost of the microprocessor system was a little less than $5,000. The time required to produce the software was 50 to 100 hrs (approximately 1 week).

The productivity potential of physicians' assistants: an integrated approach to analysis.

Abstract: Although many previous analytical studies indicate that physicians' assistants can substantially increase productivity and reduce costs, the utilization of physicians' assistants in ambulatory health care settings has grown at a disappointing rate. This apparent discrepancy may be explained in part through close examination of the models used in the analytical studies. This paper describes the limitations of previous studies and shows how analysis can be improved through the use of a combined optimization-simulation model. The model is applied to a hypothetical example to demonstrate how productivity and income benefits can be overstated, and to test the sensitivity of such benefits to a range of management policies for the ambulatory care practice regarding patient load, physical resources, appointment scheduling, and more flexible assignment of providers to patients.

A shared facility in a medical research institution

Abstract: To the Editor: Extramural certification of need by third-party carriers and state and federal governments and intramural capital equipment justifications suggest that new equipment, including information handling systems, whether dedicated or core facility, be able to handle a variety of tasks in order to ensure that systems do not stand idle. The following example of a previously dedicated computer facility may suggest avenues of justification that were not previously apparent to prospective purchasers and system designers of small facilities. The need within the Radiation Safety Office, the responsibilities of which include servicing a Nuclear Regulatory Commission Specific License of Broad Scope for radioactive materials, was to meet the license requirement that the office have on hand an inventory of radioactive materials held by each authorized user within the institution. I Each individual inventory listing must be verified quarterly by the authorized user. License requirements also include a specification that radioactive materials be separated by isotope. Therefore, for each individual user within the medical center, a listing of all materials labeled with tritium are to appear on one page; a second page will include all materials labeled with 14C. Note that a shipment received early in the year may last through the entire year, and perhaps shipments received later on are used on receipt. Furthermore, for additional purposes of identification, the Radiation Safety Office assigns an institutional identification number to each vial of material received and lists the manufacturer, manufacturer's catalog number, date of receipt, and initial activity in the vial. Summing up, Radiation Safety Office records must service approximately 50 different laboratories, each authorized to use at least 3 and some as many as 10 different isotopes in several different chemical forms with each individual shipment logged chronologically. Given 50 authorized users with an average of 5 different isotopes authorized per laboratory and perhaps four different chemical forms of each isotope, this results in a possible 1,000 line entries each quarter. Approximately 50 man-hours were consumed each quarter in order to prepare master listings and to photocopy, collate, and mail these listings out, log their return, and update the masters for the 250 files. Updating of files includes addition of receipts, decreasing the activity remaining in individual vials due to use, and deletion of entire line entries for vials whose contents have been depleted. This presents a classical case of scheduled, sequential updating of files. The computer, an Artronix PC-12, was purchased by the Radiation Ontology

Gathering diagnostic statistics.

Abstract: There is currently a dearth of numerical data on symptom occurrence for medical diseases. These data would be useful in many computer applications to medicine, particularly for computer-assisted diagnosis, computer-based clinical simulations, and computer-assisted instructions. These data might be obtained from (1) published review articles, (2) combined data bases already developed for previous automated diagnosis programs, (3) retrospective chart reviews, (4) computerized medical information systems, or (5) data supplied by expert committees. Each of these techniques has drawbacks, especially in providing data for multiple time cuts throughout the disease course, and in accounting for prior therapies, the interactions of symptoms, or the locality, sex, race, or environment of the patient. However, even a preliminary effort documenting the judgment of expert committee members would be a substantial contribution and would facilitate further progress in important areas of medical computing.

Confidentiality—Appropriate, but ...

Abstract: The confidential nature of the exchange of information between physician and patient is fundamental to the success of the medical encounter. Accordingly, except in those societies in which personal freedoms have been bankrupted in the service of political exigencies, this private character of personal medical data per se has seldom come under attack. Notwithstanding the general agreement as to the importance of confidentiality, medical data nevertheless exist within an increasingly complex health care delivery system buttressed by an equally esoteric, information science technology. Consequently, confidentiality of medical data has surfaced as an issue not in terms of the virtue of the concept but rather in terms of preservation of the concept. The most recent assault upon the preservation of the concept of confidentiality of medical data is exposed in the July 21, 1978, issue of the FederalRegister (43:31371). In this issue, a proposed rule entitled \"Access to Employee Exposure and Medical Records\" is described. This rule would, in effect, require employers to make available all employee health records to the Occupational Safety and Health Administration (OSHA) and the National Institute of Occupational Safety and Health (NIOSH). Significantly, the proposed rule indicates the transfer of all employee health data, not only those data related to health hazard exposure or occupational health standards. If one considers the enormous attention given the issue of personal privacy over the past several years, in both the public and the private sector, one can only conclude that the OSHA and NIOSH administrators have recently been released from a time capsule or have returned from a 5-year vacation.

Distributed processing techniques: interface design for interactive information sharing.

Abstract: The Information Systems Division of the University of Iowa Hospitals and Clinics has successfully designed and implemented a set of generalized interface data-handling routines that control message traffic between a satellite minicomputer in a clinical laboratory and a large main-frame computer. A special queue status inquiry transaction has also been developed that displays the current message-processing backlog and other system performance information. The design and operation of these programs are discussed in detail, with special emphasis on the message-queuing and verification techniques required in a distributed processing environment.

Computerized call scheduling for hospital departments.

Abstract: A computerized system that assigns personnel to night-call and daytime duty is described. The system reduces the department's scheduling effort from days to hours each month. It provides an equitable and unbiased assignment of staff to tasks. Information about individual qualifications and availability and about the tasks to which individuals can be assigned is entered on standard forms each month. This information is transformed into a suitable format for entering into the computer via a typerwriter terminal. The computer generates a series of schedules that are printed at the terminal in a number of formats, depending upon the nature of the schedule and the type of summary requested. Equitable schedules are produced with a minimum of administrative effort. The system increases accuracy and summarizes information for control and planning.