PaperChase: a computer program to search the medical literature

Grateful Med: Direct access to MEDLINE for health professionals with personal computers

Donald A.B. Lindberg M.D. arrived as Director, U.S. National Library of Medicine (NLM) in late 1984 with the intention of implementing a physician-friendly interface to MEDLINE, a prime example of his interest in making NLM information services more directly useful in medical care. By early 1986, NLM’s Grateful Med, an inexpensive PC search interface to MEDLINE useful for health professionals, had joined the group of end-user systems for searching MEDLINE that emerged in the 1980s. This chapter recounts Grateful Med’s rapid iterative development and the subsequent campaign to bring it to attention of health professionals. It emphasizes Lindberg’s role, the challenges faced by those introducing and using the interface in a pre-Internet world, and some longer-term effects of the effort to expand health professionals’ use of MEDLINE during the decade from 1986 to 1996.

Duration of lead time in screening for lung cancer

BACKGROUND

Screening for lung cancer has used chest radiography (CR), low dose computed tomography (LDCT) and sputum cytology (SC). Estimates of the lead time (LT), i.e., the time interval from detection of lung cancer by screening to the development of symptoms, have been derived from longitudinal studies of populations at risk, tumor doubling time (DT), the ratio between its prevalence at the first round of screening and its annual incidence during follow-up, and by probability modeling derived from the results of screening trials.

OBJECTIVE

To review and update the estimates of LT of lung cancer.

METHODS

A non-systematic search of the literature for estimates of LT and screening trials. Search of the reference sections of the retrieved papers for additional relevant studies. Calculation of LTs derived from these studies.

RESULTS

LT since detection by CR was 0.8-1.1 years if derived from longitudinal studies; 0.6-2.1 years if derived from prevalence / incidence ratios; 0.2 years if derived from the average tumor DT; and 0.2-1.0 if derived from probability modeling. LT since detection by LDCT was 1.1-3.5 if derived from prevalence / incidence ratios; 3.9 if derived from DT; and 0.9 if derived from probability modeling. LT since detection of squamous cell cancer by SC in persons with normal CR was 1.3-1.5 if derived from prevalence/incidence ratios; and 2.1 years if derived from the DT of squamous cell cancer.

CONCLUSIONS

Most estimates of the LT yield values of 0.2-1.5 years for detection by CR; of 0.9-3.5 years for detection by LDCT; and about 2 years or less for detection of squamous cell cancer by SC in persons with normal CR. The heterogeneity of the screening trials and methods of derivation may account for the variability of LT estimates.

Expert systems and library/information work

This article discusses some possible applications for expert systems in the library/information field. Definitions of expert systems and descriptions of operational systems are included. A number of areas for future research are identified.

Impressions of an old master: hospital libraries and librarians, 1970-2014

This article is a retrospective look at the changes in hospital libraries from 1970 to 2014 based on the author's experience and a survey of the literature related to hospital libraries indexed in PubMed from 1970 to the present. New roles for librarians and methods for conveying the value of libraries to administrators are described.

Changes in wellbeing and professional values among medical undergraduate students: a narrative review of the literature

BACKGROUND

Educators are concerned by the high prevalence of emotional distress among medical students, and by the alleged decline in their humanitarian values.

OBJECTIVE

To re-examine these concerns by reviewing studies of medical students' wellbeing and development.

METHOD

Narrative review of the literature.

MAIN FINDINGS

(a) Medical students' emotional distress increases during their undergraduate training. However, although higher than in the general population, the prevalence of distress among medical students is similar to that among other university students. (b) Medical students' distress is independently related to endogenous factors (personality traits and life events) and to their perception of the medical learning environment. (c) Medical students do not display a measurable increase in moral reasoning, empathy and tolerance of uncertainty. (d) Students' wellbeing, moral development, reflectivity and tolerance of uncertainty have been shown to be interrelated, and associated with clinical performance.

CONCLUSIONS

The findings of this review endorse the concerns about the wellbeing and development of undergraduate medical students. The design of the reviewed studies does not permit inferences about causality. Yet, these findings are consistent with the hypothesis that medical training causes emotional distress that delays students' development and affects their clinical performance.

Undesirable features of the medical learning environment: a narrative review of the literature

The objective of this narrative review of the literature is to draw attention to four undesirable features of the medical learning environment (MLE). First, students' fears of personal inadequacy and making errors are enhanced rather than alleviated by the hidden curriculum of the clinical teaching setting; second, the MLE projects a denial of uncertainty, although to a lesser degree than in the past; third, many students feel publicly belittled and subject to other forms of abuse; and fourth, the MLE fails in overcoming students' prejudice against mental illness and reluctance to seek help when emotionally distressed. The variability of students' appreciation of the MLE across medical schools, as well as across clinical departments within medical schools, suggests that the unwanted aspects of the MLE are modifiable. Indeed, there have been calls to promote a "nurturing" MLE, in which medical students are treated as junior colleagues. It stands to reason that faculty cannot humiliate medical students and still expect them to respect patients, just as it is impossible to ignore students' distress, and still teach them to empathize with patients. Hopefully, an egalitarian attitude to students will make them also realize that they are not alone in their fears, and that their instructors share their doubts. Therefore, a major challenge of contemporary medical education is to advance a clinical MLE, where errors and uncertainties are acknowledged rather than denied, and trainees are trusted and supported, rather than judged and, occasionally, derided.

The effect of clinical interventions on hospital readmissions: a meta-review of published meta-analyses

BACKGROUND

The economic impact and ease of measurement of all-cause hospital readmission rates (HRR) have led to the current debate as to whether they are reducible, and whether they should be used as a publicly reported quality indicators of medical care.

OBJECTIVE

To assess the efficacy of broad clinical interventions in preventing HRR of patients with chronic diseases

METHOD

A meta-review of published systematic reviews of randomized controlled trials (RCTs) of clinical interventions that have included HRR among the patients' outcomes of interest.

MAIN FINDINGS

Meta-analyses of RCTs have consistently found that, in the community, disease management programs significantly reduced HRR in patients with heart failure, coronary heart disease and bronchial asthma, but not in patients with stroke and in unselected patients with chronic disorders. Inhospital interventions, such as discharge planning, pharmacological consultations and multidisciplinary care, and community interventions in patients with chronic obstructive pulmonary diseases had an inconsistent effect on HRR. MAIN STUDY LIMITATION: Despite their economic impact and ease of measurement, HRR are not the most important outcome of patient care, and efforts aimed at their reduction may compromise patients' health by reducing also justified re-admissions.

CONCLUSIONS

The efficacy of inhospital interventions in reducing HRR is in need of further study. In patients with heart diseases and bronchial asthma, HRR may be considered as a publicly reported quality indicator of community care, provided that future research confirms that efforts to reduce HRR do not adversely affect other patients' outcomes, such as mortality, functional capacity and quality of life. Future research should also focus on the reasons for the higher efficacy of community interventions in patients with heart diseases and bronchial asthma than in those with other chronic diseases.

Objectives of teaching direct ophthalmoscopy to medical students

PURPOSE

To propose the objectives of undergraduate training in direct ophthalmoscopy (DO).

METHOD

Narrative review of the literature on (i) opinions about the expected proficiency from students in DO, and (ii) estimates of its diagnostic value.

RESULTS

(i) Authorities disagree on the proficiency in DO that they expect from students. Textbooks of physical diagnosis differ in their coverage of DO. Surveys have indicated that US physicians expect students to be able to detect optic nerve head abnormalities. The Association of American Medical Colleges expects students to perform ophthalmoscopic examination and describe observations. The International Council of Ophthalmology expects students to recognize also diabetic and hypertensive retinopathies. The Association of University Professors in Ophthalmology requires that students recognize papilloedema, cholesterol emboli, glaucomatous cupping and macular degeneration. (ii) There is evidence that DO, even by ophthalmologists, is inadequate for screening for glaucoma, diabetic and hypertensive retinopathies. Two studies have suggested a limited value of DO in detecting clinical emergencies.

CONCLUSIONS

The evidence that DO, even by ophthalmologists, is sub-optimal in detecting common abnormalities challenges existing the notions of training medical students. On pending the results of additional studies of the value of DO in detecting emergencies, we suggest that undergraduate teaching of DO should impart the following: (i) an ability to identify the red fundus reflex and optic disc; (ii) an ability to recognize signs of clinical emergencies in patients, mannequins or fundus photographs; and (iii) knowledge about, but not an ability to detect, other retinopathies.

Narrative review: should teaching of the respiratory physical examination be restricted only to signs with proven reliability and validity?

OBJECTIVE

To review the reported reliability (reproducibility, inter-examiner agreement) and validity (sensitivity, specificity and likelihood ratios) of respiratory physical examination (PE) signs, and suggest an approach to teaching these signs to medical students.

METHODS

Review of the literature. We searched Paper Chase between 1966 and June 2009 to identify and evaluate published studies on the diagnostic accuracy of respiratory PE signs.

RESULTS

Most studies have reported low to fair reliability and sensitivity values. However, some studies have found high specificites for selected PE signs. None of the studies that we reviewed adhered to all of the STARD criteria for reporting diagnostic accuracy.

CONCLUSIONS

Possible flaws in study designs may have led to underestimates of the observed diagnostic accuracy of respiratory PE signs. The reported poor reliabilities may have been due to differences in the PE skills of the participating examiners, while the sensitivities may have been confounded by variations in the severity of the diseases of the participating patients. IMPLICATION FOR PRACTICE AND MEDICAL EDUCATION: Pending the results of properly controlled studies, the reported poor reliability and sensitivity of most respiratory PE signs do not necessarily detract from their clinical utility. Therefore, we believe that a meticulously performed respiratory PE, which aims to explore a diagnostic hypothesis, as opposed to a PE that aims to detect a disease in an asymptomatic person, remains a cornerstone of clinical practice. We propose teaching the respiratory PE signs according to their importance, beginning with signs of life-threatening conditions and those that have been reported to have a high specificity, and ending with signs that are "nice to know," but are no longer employed because of the availability of more easily performed tests.

Reflections on electronic medical records: when doctors will use them and when they will not

PURPOSE

Our purpose is to counter the common wisdom that doctors are refractory to change and therefore responsible for the limited use of electronic medical records.

METHODS

We draw on experience with electronic medical records in two Harvard Medical School teaching hospitals dating back to the early 1980s.

RESULTS

Doctors quickly become ardent users of electronic medical records if the software is sufficiently helpful in the care of their patients.

CONCLUSIONS

The key to enthusiastic acceptance of electronic medical records is computing that is easy to use and helpful to doctors, nurses, and other clinicians in the care of their patients.

Medical subject headings used to search the biomedical literature

The National Library of Medicine's MEDLINE (MEDLARS Online) database was the first database to be searched nationwide via value-added telecommunication networks. Now available on the World Wide Web free of charge from the National Library of Medicine and from many other sources, it is the world's most heavily used medical database. MEDLINE is unique in that each reference to the medical literature is indexed under a controlled vocabulary called Medical Subject Headings (MeSH). These headings are the keys that unlock the medical literature. MeSH multiplies the usefulness of the MEDLINE database and makes it possible to search the medical literature as we do today. This paper commemorates the 40th anniversary of the introduction of MeSH and salutes some of the farsighted persons who conceived and developed the MEDLINE database.

Medical narratives in electronic medical records

In this article, we describe the state of the art and directions of current development and research with respect to the inclusion of medical narratives in electronic medical-record systems. We used information about 20 electronic medical-record systems as presented in the literature. We divided these systems into 'classical' systems that matured before 1990 and are now used in a broad range of medical domains, and 'experimental' systems, more recently developed and, in general, more innovative. In the literature, three major challenges were addressed: facilitation of direct data entry, achieving unambiguous understandability of data, and improvement of data presentation. Promising approaches to tackle the first and second challenge are the use of dynamic data-entry forms that anticipate sensible input, and free-text data entry followed by natural-language interpretation. Both these approaches require a highly expressive medical terminology. How to facilitate the access to medical narratives has not been studied much. We found facilitating examples of presenting this information as fluent prose, of optimising the screen design with fixed position cues, and of imposing medical narratives with a structure of indexable paragraphs that can be used in flowsheets. We conclude that further study is needed to develop an optimal searching structure for medical narratives.

Clinical Information Systems for Intensive Care, Pediatric Critical Care, and Neonatology

Computer information systems are expected to soon take the place of current paper charting practices, and they offer great promise to assist management of the considerable amounts of data encountered in the information-rich environment of intensive care units (ICUs). Efforts to create an electronic medical record (EMR) have been underway for more than two decades, and major national organizations, such as the Institute of Medicine, have issued recommendations on standards. Benefits of an EMR include a legible patient record, enhanced communication, provision of timely reminders and alerts to clinicians, reduction of calculation errors, access to data bases for quality assurance and research, reduced healthcare costs, and improved patient outcomes. Despite these benefits, successful EMR implementations have been confined to a few committed institutions, and expensive failures have occurred. Practitioners of neonatology and pediatric intensive care are likely to have substantial difficulty implementing an EMR to fit their specialized needs because most experience in this area has been gained through care of adult patients, and systems being developed are oriented toward nonpediatric patients. It is therefore important to examine experience thus far with the functional components of an EMR so practitioners will be able to evaluate systems better as they become available. System components discussed include nursing charting facilities, lab reporting, physician order entry, physician progress notes, structured reports, decision support systems, and problem list management. Other concerns discussed include research and quality assurance functions, data access and confidentiality issues, and electronic mail. Maximizing the “structured data” content, as opposed to narrative content of an EMR, is an important priority, and progress on developing a uniform medical language is discussed. An approach to evaluating clinical information systems for use in the ICU is presented; it should assist practitioners of pediatric critical care and neonatology in identifying computer-based charting solutions that are optimal for infants and children, while cooperating with medical center-wide needs for compatibility and a common data base.

Decision support in healthcare

To address the recognized problems associated with information overload and limited human memory, computer-based systems which help healthcare providers use information to make better decisions have been developed and implemented. These decision aids are designed to improve the quality and reduce the cost of healthcare. Currently, the most widely used computer application is to simply provide needed facts about the patient in an organized and timely fashion. Additionally, healthcare workers can access literature, ask questions of aggregates of patient data for clinical or administrative decisions, receive warnings or suggestions when the patient's data satisfy certain logical rules receive critiques when proposing therapies or ordering diagnostic tests, receive guidelines for standards of care, access programs which analyze tradeoffs and likelihoods of alternative outcomes (decision analysis) and receive lists of differential diagnoses. Given this wonderful panoply of capabilities, the question becomes 'why aren't more people using these aids and what are the demonstrated benefits of such capabilities?' In this paper we review the types of decision aids which have been successfully implemented and the challenges to implementation (knowledge representation, connections to databases, need for comprehensive, coded databases and evaluation of benefits).

MEDLINE training for medical students integrated into the clinical curriculum

This study was initiated in response to the availabilty of unlimited access to MEDLINE via the PaperChase interface at the host institution. The goal of the study was to analyse the usage of MEDLINE by medical students during their third-year clinical clerkship in paediatrics. This was achieved by first giving them a formal demonstration of MEDLINE and then longitudinally administering a structured questionnaire at several points during their paediatric clerkship. Since medical students were required to write a thesis for this clerkship, which included an analysis of the primary literature, there was an identified need for using the system. This study analyses the students' perceptions and searching activities after formal training and upon having unlimited access to MEDLINE.

The electronic information revolution and how to exploit it

Medical information is increasingly stored in electronic format, enabling faster and more flexible access to the literature. Online, compact disc and floppy disc databases are widely available. The origins and development of these different database media are described. The strengths and weaknesses of each, and the ways in which they complement each other, are examined. Ease of access to medical information can result in data management problems; the role of bibliographic software in ensuring full exploitation of the electronic information revolution is therefore emphasized.

Medical informatics in postgraduate training: a way to improve office-based practitioner information management

Medical informatics has the potential to revolutionize patient care by providing every physician with rapid, easy access to the entire medical knowledge base. However, many changes are needed in the way systems are designed and physicians are trained before this potential can be realized. It is the shared responsibility of the medical informatics community, professional societies, academic organizations, and practitioners to accept the challenge of turning the power and promise of modern computer technology into useful tools for the care of patients.

Implementing a computer system for psychiatric training : the electric resident

The Electric Resident System is an experimental arrangement of software for the personal computer. It is designed to help residents in the educational cycle of patient interview, literature review, write-up, attending review, and patient treatment. The authors emphasize the system's immediate utility and ease of operation, using a graphical interface. Within a year of operation this system was in daily use on a consultation service with minimal formal instruction. Usage data show a positive correlation between the number of patients seen per month and the number of computer-assisted MEDLINE literature searches performed. Residents' comments indicate not only acceptance of the system but increased interest in computer applications in medical care. The Electric Resident System is meant to be the first step toward a computer-aided residency.

Using routinely collected data for clinical research

Clinical research involving prospective data collection in randomized controlled trials is not always feasible. Increasingly, hospitals are developing large clinical databases that are waiting to be mined. We have developed a computer program, ClinQuery, that facilitates such exploration and analysis. We have also shown in a series of studies that the use of clinical data is a powerful tool in health services research. In some cases, we have shown that coded data are inaccurate and that alternative clinical data are preferable. In other cases, a combination of clinical data and coded discharge diagnoses is preferable.

The new information technologies and psychiatry

The author reviews the history and technology of the microcomputer and discusses the various classes of software that are presently available. Three major categories of software are described: numeric data processing, text processing, and communications. The application of this software to psychiatric education and practice is briefly discussed. A short curriculum on computers for psychiatric residents is outlined, and a brief bibliography of the recent relevant literature on computer applications to medicine and psychiatry is presented. Predictions are made about the future direction of computer technology and its application to psychiatry.

Self-service computerized bibliographic retrieval: a comparison of Colleague and PaperChase, programs that search the MEDLINE data base

Colleague and PaperChase are the two most widely used computer systems designed specifically for clinicians and scientists who wish to search the National Library of Medicine's MEDLINE data base of references to the biomedical literature. The present study compares the performance of these two systems. Two matched groups of second-year medical students each received 3 hr of instruction, one group in Colleague, the other in PaperChase. Each student then attempted 10 test searches. The next day the groups were reversed, and each student attempted 5 additional searches. During 3 1/2 hr allocated for searching, users of Colleague attempted 64 test searches and retrieved 326 target references; users of PaperChase attempted 78 searches and retrieved 496. Users of Colleague took a mean of 2.2 min and spent a mean of $1.20 to find each target reference; users of PaperChase took 1.6 min and spent $0.92. We conclude that after limited training, medical students find more references faster and at lower cost with PaperChase than with Colleague.

Reference master: a microcomputer-based storage and retrieval system for bibliographic references

A complete system for housekeeping and retrieval of bibliographic references managing individual reprint collections is described. By the use of special hardware and individual data base software even large reprint collections in the range up to 65,000 papers are handled economically. A fast 8-bit microprocessor (HD 64180) in combination with a Winchester hard disk drive serves as the basis for rapid access to the desired information. An efficient string search algorithm written in assembly language guarantees a fast operation with a search speed of more than 6,000 entries/minute. The system cannot only prepare reference lists and reference files, but also incorporates an editor and maintains the control whether reprints are already on file or requested. The implementation of back-up schemes assure against data losses. Using a state of the art design single board computer and the most recent mass storage device technology, the system is as well small and cost effective, and thus suitable for personal use. In addition, some general questions and pitfalls concerning the management of scientific literature collections are touched upon.

Automated translation of German to English medical text

The feasibility of automated translation of scientific and medical documents remains controversial. This report describes a minicomputer-based German-to-English translation system (TRANSOFT) that employs word order rearrangement followed by word-for-word translation and disambiguation based on context. This translation system was applied to a computer-readable version of Adler's Knochenkrankheiten (Bone Diseases), which contains 118,604 words, with 10,216 distinct words in 7,211 sentences averaging 16.4 words each. The translation required 2,791 word rearrangement formulas, 78 percent of which were first used in the first half of the document. There were 2,392 occurrences of 12 potentially ambiguous terms, of which only 18 (0.8 percent) were not resolvable from the immediate context. As foreign language medical documents become increasingly available in computer-readable form through computerized typesetting, electronic publishing, and improved optical character recognition equipment, automated translation systems may provide a rapid and inexpensive means of obtaining draft translations.

Observations of end-user online searching behavior over eleven years

End-user searching of National Library of Medicine (NLM) online data bases during eleven years has been investigated through transaction logs, questionnaires, and follow-up interviews. From 1976 through 1984, pathologists and pharmacists performed 8,313 searches. Highlights of our studies are compared with a review of other end-user research. Volume of searching is directly related to the convenient placement of the terminal in the work place. Slightly fewer than half of all potential searchers actually search for themselves. Practices of pharmacists and pathologists do not differ in important ways. Nonmediated searchers feel they need answers more promptly than do those who obtain mediated searches. End-users perform very simple searches, mostly using only the AND operator. Problems with techniques are fewer and more easily solved than those with the vocabulary and content of the system. The major problems, with the most powerful capabilities of MEDLINE--subheadings and explosions--sometimes cause substantial loss of references, but in relatively few searches. One-on-one teaching is most popular, with trial-and-error the most frequent procedure used in actual learning.

Medical telecommunications--fundamental changes in the art and science of medicine

The availability of easy to use microcomputers and medical information retrieval systems will result in fundamental and important changes in medical practice. The acquisition of information literacy and fluency will be mandatory techniques for the future practice of medicine and should be taught at the institutional level by faculty sophisticated in the use of information retrieval systems. The resulting improvements in the practice of medicine go beyond simple cost savings to fundamentally alter the ways patients and their disorders are looked upon and handled.

Clinical computing in a teaching hospital

This report describes a hospital-wide clinical computing system that permits physicians, nurses, medical students, and other health workers to retrieve data from the clinical laboratories; to look up reports from the departments of radiology and pathology; to look up demographic data and outpatient visits; to look up prescriptions filled in the outpatient pharmacy; to perform bibliographic retrieval of the MEDLINE data base; to read, write, retract, edit, and forward electronic mail; and to request delivery of a patient's chart. During a one-week study period, from 300 video display terminals located throughout the hospital, 818 patient care providers used a common registry of 539,000 patients to look up clinical and laboratory data 16,768 times; 477 other hospital workers used the patient registry 46,579 times. In a separate study of 586 health care providers, 470 (80 per cent) indicated that they used computer terminals "most of the time" to look up laboratory results; in contrast, 48 (8 per cent) preferred printed reports. Of 545 hospital workers, 440 (81 per cent) indicated that the computer terminals definitely or probably made their work more accurate, and 452 (83 per cent) indicated that terminals enabled them to work faster. The large amount of use by clinicians and their judgment that the computer has been so helpful to them suggests that a reliable, comprehensive, and easy-to-use computer system can contribute substantially to the quality of patient care.

An experimental comparison of the effectiveness of computers and humans as search intermediaries

An experimental computer intermediary system, CONIT, that assists users in accessing and searching heterogeneous retrieval systems has been enhanced with various search aids. Controlled experiments have been conducted to compare the effectiveness of the enhanced CONIT intermediary with that of human expert intermediary search specialists. Some 16 end users, none of whom had previously operated either CONIT or any of the four connected retrieval systems, performed searches on 20 different topics using CONIT with no assistance other than that provided by CONIT itself (except to recover from computer/software bugs). These same users also performed searches on the same topics with the help of human expert intermediaries who searched using the retrieval systems directly. Sometimes CONIT and sometimes the human expert were clearly superior in terms of such parameters as recall and search time. In general, however, users searching alone with CONIT achieved somewhat higher online recall at the expense of longer session times. We conclude that advanced experimental intermediary techniques are now capable of providing search assistance whose effectiveness at least approximates that of human intermediaries in some contexts. Also analyzed is the cost effectiveness of current intermediary systems. Finally, consideration is given to the prospects for much more advanced systems which would perform such functions as automatic data-base selection and the simulation of human experts, and thereby make information retrieval more effective for all classes of users.

One man's answer to immunological information overload: microcomputer management of the personal reprint collection

The subject of information overload in immunology has been addressed recently by Waksman, who proposed some innovative solutions for the afferent pathways(1,2), (see also reactions by Sanderson(3), Turk(4) and Franklin(5)). Here Eric Martz describes his solution for efferent overload.

RIPS: a UNIX-based reference information program for scientists

A set of programs is described which implement a personal reference management and information retrieval system on a UNIX-based minicomputer. The system operates in a multiuser configuration with a host of user-friendly utilities that assist entry of reference material, its retrieval, and formatted printing for associated tasks. A search command language was developed without restriction in keyword vocabulary, number of keywords, or level of parenthetical expression nesting. The system is readily transported, and by design is applicable to any academic specialty.

End user touch searching for cancer therapy literature

This paper reviews work towards building an expert system for searching the cancer therapy literature on MEDLINE. A modified subset of the Medical Subject Headings (MeSH) has been stored on a micro-computer and accessed via a touch terminal. Searches, previously requested of the Oncology Information Service at the University of Leeds, have been used to test out the principle of end user searching and the results compared with the searching expertise of a MEDLARS indexer. Original program development was in PASCAL, but a rule-based approach, which is independent of a particular programming language, has been developed for search term and frame selection adopting a 'blackboard' philosophy in tracing the process of selection. Work is progressing on an implementation using the expert systems programming language PROLOG, which has been found a very suitable language for representing rules and provides a ready made rule interpreter. It is suggested that this approach is superior in terms of retrieval performance compared with alternative approaches to end-user searching which fail to exhibit detailed knowledge regarding the subject matter of the search.

A microcomputer approach to storage of qualitative patient data using key words

A microcomputer program is presented which stores and retrieves qualitative patient information, such as diagnosis and physical findings. Users can design and enter a key word list and modify it as needed. Using those key words, up to 5000 patient entries can be made on a single floppy disk. Application of the program to CT scan study results is discussed.