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Biomedical subjects

A Hasman

Publications and source records attributed to A Hasman.

At least 19 recordsLinked to original sources
PubMed1992

Inter-institutional information exchange in healthcare.

In this paper the results of the standardization efforts and an evaluation study concerning electronic data interchange (EDI) performed by the 31 (Inter Institutional Information exchange)-project are described. In an earlier paper the results of a preliminary study were reported. EDI concerns communication between autonomous information systems and therefore needs standardization of the messages to be exchanged. In the 31-project ten different types of standard messages have been defined. The use of these messages for exchanging information between hospitals, GPs and pharmacies is described. It is concluded that relatively large time savings can be obtained when communicating electronically. It is also concluded that the electronic data interchange between hospitals and GPs can be performed without additional costs. The electronic communication of prescriptions between GPs and pharmacies does raise the costs of communication at the moment. The impact of EDI on the functioning of people in the organizations involved varies widely.

Clinical Pharmacy Information Systems↗
PubMed1991

Evaluation of computerised questionnaires designed for patients referred for gastrointestinal endoscopy.

The aim of this prospective study was to assess the applicability of a computerised medical history system at the open-access endoscopy unit of a University Hospital during routine clinical practice. We studied feasibility, acceptability and reproducibility of computerised questionnaires designed for patients referred for endoscopy of either the upper or lower gastrointestinal (GI) tract, partly in comparison with almost identical paper questionnaires. In the first period of the study 1134 patients were referred of whom 73% answered the paper questionnaire, and during the second period 537 patients were referred of whom 64% answered the computerised questionnaire (P less than 0.001). There was no sex dependency regarding the ability to answer both types of questionnaires. A significant age dependency regarding the ability to answer the paper questionnaires was observed for patients referred for upper and lower GI endoscopy (P less than 0.0001 and P less than 0.0001). Corresponding with this observation, the ability to answer the computerised questionnaires significantly decreased with increasing age for both groups of patients (P less than 0.0001 and P less than 0.0001). The average completion times of both computerised questionnaires, designed for the upper and lower GI tract, were 11 min. The completion times did not depend on sex, but there was a slight positive correlation with age (P less than 0.0001 with multiple R = 0.27 and P = 0.0593 with multiple R = 0.12). Answering our computerised questionnaires was consistently reported to be interesting and easy, and did not last too long according to the respondents. After patients had answered the computerised history system, the insight into their complaints had increased in 40%, and 45% could put their complaints into words more easily. Only 25% of the patients were unable to express all their complaints. A reproducibility of medical history data of 85% was observed between paper and computerised questionnaires. Our computerised questionnaires can provide us with a detailed and uniformly acquired medical history of most patients referred for GI endoscopy. They are well accepted by the patients and can be completed during the normal waiting period. The medical history data obtained with these questionnaires are quite reproducible.

Adult↗
PubMed1991

Education and medical informatics--five years of experience at the University of Limburg.

In this paper the experience of five years of medical informatics education at the university of Limburg is described. The university of Limburg uses the problem-directed educational system. This system is described. The blocks in Medical Informatics are then presented. Then several program packages that were developed by the department of Medical Informatics of this university are described. Finally the assessment by the students of this type of education is given.

Curriculum↗
PubMed1990

Telecommunication in medicine--the 3I project.

Telecommunication in medicine is becoming increasingly important. This contribution describes a national project in the Netherlands aimed at developing standards for electronic messages and evaluation of cost and benefits of electronic data exchange.

Computer Communication Networks↗
PubMed1990

The differential ratio. A method for describing blood flow in renal transplants.

The blood flow in renal transplants can be represented by (1) a K/A ratio, the ratio of the slopes of the ascending part of the renal perfusion curve and the arterial curve, (2) a perfusion index, the ratio of a part of the area under the first-pass arterial curve and renal curve, and (3) a height ratio, the ratio of the height of the renal curve and the arterial curve at the point of time upon which the arterial curve shows its very first maximum. Because it is sometimes rather difficult to find suitable parameters for these three methods, a differential ratio is proposed, the ratio of the maxima of the 1st derivative of the first-pass renal and arterial curve. Good correlation is found between the K/A ratio and the differential ratio as well as between the perfusion index and the height ratio. This implies that the differential ratio could be used instead of the K/A ratio and that the height ratio is a very good alternative for the perfusion index.

Humans↗
PubMed1990

Noise reduction in estimating cardiac deformation from marker tracks.

Deformation of the cardiac wall is measured by using optical or radiopaque markers attached to the wall. When digitized images are used, the accuracy of the measurement of a marker position is limited by pixel resolution and the size of the marker. The spatial accuracy is improved by singular value decomposition (SVD) filtering. This filtering procedure is based on the assumption that displacements of markers are mutually related because they are embedded in a common continuum. In a computer stimulation with 48 markers in 51 video frames, the accuracy of the measurement of a marker position improved from 0.14 to 0.045 (SD) pixel. In an open-chest animal experiment, with markers on the surface of the heart, the deformation patterns were extracted more clearly using SVD filtering, while mutually related high-frequency components were not suppressed. In a 50-frame sequence of 256 X 256 video images of a 45 mm X 35 mm deforming surface with 50 markers of 8 pixels in diameter, the marker position resolution improves from 0.1 to 0.03 (SD) pixel (6 microns). Strain is determined with an accuracy of 0.002 over a distance of 30 pixels (6 mm).

Animals↗
PubMed1989

Description of a blockcourse in medical informatics.

This paper describes a blockcourse in medical informatics. The course is presented to fourth, fifth and sixth year medical students and lasts one week. During the course all aspects of medical informatics are considered. Programming, databases, information systems, signal analysis, pattern recognition, expert systems, etc. are explained. Lectures alternate with hands-on experience. The subjects discussed in the lectures are rehearsed during the practical sessions, so that gaps in the student's knowledge are immediately detected. The blockcourse has been positively rated by the students.

Computer-Assisted Instruction↗
PubMed1988

ADAMO revisited: an interpretative review of a data management system.

In this paper the use for research purposes of an existing data management system, ADAMO (A Database Management system for Oncology), is described. The aim of this paper is to discuss the experiences, obtained with this 'home-made' system and to describe some of the extensions that were recently made. Reasons are presented why the system is still extensively used by clinicians although a number of commercial database management systems is now available on personal computers. These database systems are more flexible than the system described here. It is concluded that it is precisely this flexibility of current systems that prevents an optimal use by busy clinicians. Clinicians need a research system that contains just the functions that they need. These functions have to be available via simple commands, so that no additional programming--even at the high level of a query language--is necessary.

Computer-Assisted Instruction↗
PubMed1987

Medical applications of computers: an overview.

In this review computer applications in medicine are discussed from the point of view of the levels of information processing as suggested by van Bemmel. Applications are presented and research directions indicated. The purpose of this review article is to give an overview of the field of medical informatics. A structural approach is followed in discussing the subjects of communication, databases, complex calculations (including signal analysis and image analysis techniques), pattern recognition and expert systems. The role the computer system plays in relation to the physician is discussed. It is stressed that computers cannot replace the physician, because computer systems use programs, that are of a scientific nature. This means that only certain aspects are taken into account and that one abstracts from individuality. Therefore, computers are unable to give advice about individual patients regarding their future.

Database Management Systems↗
PubMed1987

A research tool for general practitioners.

In this paper a research tool for general practitioners is described, that will be used in a network of community-based primary care practices in order to collect the necessary data for research purpose. The research tool is coupled to a commercial information system for general practitioners. The research tool supports coding strongly. The way in which the research tool is designed is described and examples of the use of windowing techniques are given.

Family Practice↗
PubMed1987

Automation of the patient history--evaluation of ergonomic aspects.

In this study it was investigated in quantitative terms how patient reactions were on automated history-taking. The study is part of a comprehensive project, in which also physicians participated in the validation of such computerized medical records. In total 99 patients, visiting the outpatient clinic of Internal Medicine for the first time, took part in this in-depth study, in which they could express themselves via an interactive and modified terminal and keyboard. The questionnaire that was used in the system contains 28 different screens. Patient complaints are entered together with data on frequency, severity, onset, and duration. The patient may indicate his physical complaints on a stylized picture of the human body. Of the 99 patients, 67 answered the full questionnaire, and another 16 the main part. On the average, 66 min were needed. Younger patients do complete the history in a significantly shorter time than older patients, resulting in relatively more completed histories for the younger group. Quick patients answered on the average 3.5 questions per minute, the slow patients only 2.5. This was strongly correlated with patient familiarization, that has also been investigated: patients who had a quick familiarization were able to finish within 50 min. Patients who needed no help at all in using the system had even answering rates of 3.9/min.

Adult↗
PubMed1987

Heterogeneity of stage II glottic carcinoma and its therapeutic implications.

The heterogeneity of glottic carcinoma results in variable loco-regional control probabilities from 40 to 80%. These widely different results may be due to two prognostic parameters of the tumor: the mobility of the vocal cord and the volume of the tumor. On the other hand radiation dose and technique may influence the treatment results. Stringent work-up has been prospectively undertaken in 156 patients with Stage II glottic carcinoma since 1974 through 1983 in the Academic Hospital of the Free University in Amsterdam. Several subgroups were defined from the beginning to indicate one or both of these prognostic factors. All were treated with a high quality accurate radiation therapy program delivering high dose to all patients with worse prognostic factors and even higher dosages to voluminous tumors with impaired mobility of a cord or slowly regressing tumors. The latter was individually judged for each patient towards the end of the treatment period. The loco-regional control probability of around 80% for all the subgroups irrespective of the prognostic factors indicate that the heterogeneity of Stage II glottic cancer may be influenced by high dosages of quality controlled radiotherapy. Thus results hitherto reported in literature may be further improved by the dose-schedules outlined here.

Adult↗
PubMed1987

Radiation therapy for advanced (T3T4N0-N3M0) laryngeal carcinoma: the need for a change of strategy: a radiotherapeutic viewpoint.

Since 1974 through 1984, 137 selected patients with loco-regionally advanced carcinoma of the larynx (T3T4 N0-N3) were treated primarily with quality controlled high dose megavoltage radiation therapy with salvage surgery in reserve. This policy of treatment has yielded 67% loco-regional control probability with primary radiotherapy and 85% with salvage surgery at 3 years. Fourteen patients (14/38) had moderate to severe complications after salvage surgery. The quality of life of the patients successfully treated by radiation therapy is obviously and unquestionably better. Primary radiotherapy with salvage surgery in reserve should be accepted as the strategy of choice in at least a selected group of patients with advanced laryngeal carcinoma.

Aged↗
PubMed1986

Appraisal of computerized medical histories: comparisons between computerized and conventional records.

Automated patient histories in internal medicine have been compared with written medical records by investigating the diagnostic statements that were generated for both types of records by three internists. Also the intra and interobserver variability was evaluated. In addition, the opinion of the internists about the usability of the different records was investigated. To have a fair comparison, the written record was transcribed to a computerized form and also offered to the internists. Each internist evaluated in total 72 records (from 18 patients) and altogether 529 diagnostic hypotheses were generated. The intraobserver agreement was for the written record 55%, for the automated history 46% and for the transcribed record 38%. Interobserver agreement was 23.5%, the agreement between the automated patient history and the written record was 24%, between the former and the transcribed record it was 36%.

Computer Systems↗
PubMed1986

A data management system to assist hypertension treatment in primary health care.

A data management system has been developed with respect to the treatment of hypertension and other cardiovascular risk factors. With this data management system as a tool, cooperation between the general practitioner and a specialist physician could be implemented. The system was successfully tested in a group-practice of two general practitioners. Individual follow-up became more tangible. Observations in the patients as a group warranted a modest opinion about hypertension management in view of the number of undetected hypertensives, the number of drop-outs, and the failures in treatment. The set-up functioned satisfactorily. Further application of the system on a wider scale is feasible. Improvement of treatment by a cautiously operating specialist physician is within reach of general practice, even if health care is not regionalized.

Antihypertensive Agents↗
PubMed1985

A computer program for the analysis of serial electrocardiograms from patients who suffered a myocardial infarction.

A program is described, which compares serial ECG recordings of patients, who suffered a myocardial infarction. The comparison of the ECGs is based on the measurements, delivered by the Modular ECG/VCG Interpretation System. The two most recent ECGs are compared and a trend analysis based on all ECG recordings of the patient is performed. The criteria in the comparison program are based, among others, on data obtained from a combined cardiological and respiratory survey in The Netherlands in 1973 and 1976.

Computers↗
PubMed1979

A data storage and retrieval system for clinical research.

A data storage and retrieval system is presented that can be used for clinical research studies. The system is designed in such a way that the programs are independent of the application. It can be used by non-computer experts via a simple query language. Since it is bulit up in a modular way extensions can be easily made. The system is implemented on a PDP 11/70 under FORTRAN.

Computers↗