| 1. |
- Ellenius, Johan, et al.
(författare)
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Methods for selection of adequate neural network structures with application to early assessment of chest pain patients by biochemical monitoring
- 2000
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Ingår i: International Journal of Medical Informatics. - 1386-5056 .- 1872-8243. ; 57:2-3, s. 181-202
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Tidskriftsartikel (refereegranskat)abstract
- A methodology for selecting, training and estimating the performance of adequate artificial neural network (ANN) structures and incorporating them with algorithms that are optimized for clinical decision making is presented. The methodology was applied to the problem of early ruling-in/ruling-out of patients with suspected acute myocardial infarction using frequent biochemical monitoring. The selection of adequate ANN structures from a set of candidates was based on criteria for model compatibility, parameter identifiability and diagnostic performance. The candidate ANN structures evaluated were the single-layer perceptron (SLP), the fuzzified SLP, the multiple SLP, the gated multiple SLP, the multi-layer perceptron (MLP) and the discrete-time recursive neural network. The identifiability of the ANNs was assessed in terms of the conditioning of the Hessian of the objective function, and variability of parameter estimates and decision boundaries in the trials of leave-one-out cross-validation. The commonly used MLP was shown to be non-identifiable for the present problem and available amount of data, despite artificially reducing the model complexity with use of regularization methods. The investigation is concluded by recommending a number of guidelines in order to obtain an adequate ANN model.
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| 2. |
- Ellenius, Johan, et al.
(författare)
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Transferability of neural network-based decision support algorithms for early assessment of chest-pain patients
- 2000
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Ingår i: International Journal of Medical Informatics. - 1386-5056 .- 1872-8243. ; 60:1, s. 1-20
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Tidskriftsartikel (refereegranskat)abstract
- The present investigation concerns methodological and epidemiological aspects of the transferability of artificial neural network-based algorithms, as key-components for classification in decision support systems (DSS). The prevalence of pathological conditions to be detected must be known in order to tune an artificial neural networks (ANN)-decision algorithm so that the predictive values of the outcome fulfil medical requirements. Another aspect of transferability, when clinical laboratory results are used, concerns differences in analytical performance of measuring instruments. The relative bias between two instruments is not known exactly, but must be estimated and corrected for. A general method, based on original measured data sets and statistical modeling, was developed for simulating the impact of various correction procedures when using different analytical instruments. The simulation methodology was applied to a real clinical problem of ruling-in/ruling-out of patients with suspected acute myocardial infarction (AMI) by biochemical monitoring. The recommended correction procedure was based on method comparison with use of five duplicate measurements on a common set of patient samples covering the relevant measuring interval. Transferability of laboratory data over time was also studied. The design of quality assurance procedures should be based on analytical quality requirement specifications related to medical needs. Limits of critically sized systematic errors were assessed by calculating the decrease in diagnostic performance of the ANN-algorithm as a result of temporary analytical disturbances. The consequences for the design of QA procedures was illustrated. It is concluded that the actual ANN-decision algorithm for early assessment of chest-pain patients should be possible to transfer to new sites under realistic conditions.
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| 3. |
- Franzén, Kristofer, et al.
(författare)
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Protein names and how to find them
- 2002. - 1
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Ingår i: International Journal of Medical Informatics. - : Elsevier. - 1386-5056 .- 1872-8243. ; 67, s. 49-61
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Tidskriftsartikel (refereegranskat)abstract
- A prerequisite for all higher level information extraction tasks is the identification of unknown names in text. Today, when large corpora can consist of billions of words, it is of utmost importance to develop accurate techniques for the automatic detection, extraction and categorization of named entities in these corpora. Although named entity recognition might be regarded a solved problem in some domains, it still poses a significant challenge in others. In this work we focus on one of the more difficult tasks, the identification of protein names in text. This task presents several interesting difficulties because of the named entities' variant structural characteristics, their sometimes unclear status as names, the lack of common standards and fixed nomenclatures, and the specifics of the texts in the molecular biology domain in which they appear. We describe how we approached these and other difficulties in the implementation of Yapex, a system for the automatic identification of protein names in text. We also evaluate Yapex under four different notions of correctness and compare its performance to that of another publicly available system for protein name recognition.
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| 4. |
- Lind, Leili, et al.
(författare)
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Requirements and prototyping of a home health care application based on emerging JAVA technology.
- 2002
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Ingår i: International Journal of Medical Informatics. - 1386-5056 .- 1872-8243. ; 68:1-3, s. 129-139
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Tidskriftsartikel (refereegranskat)abstract
- IT support for home health care is an expanding area within health care IT development. Home health care differs from other in- or outpatient care delivery forms in a number of ways, and thus, the introduction of home health care applications must be based on a rigorous analysis of necessary requirements to secure safe and reliable health care. This article reports early experiences from the development of a home health care application based on emerging technologies. A prototype application for the follow-up of diabetes patients is presented and discussed in relation to a list of general requirements on home health care applications.
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| 5. |
- Nilsson, Gunnar, et al.
(författare)
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Computerisation, coding, data retrieval and related attitudes among Swedish general practitioners - A survey of necessary conditions for a database of diseases and health problems
- 2002
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Ingår i: International Journal of Medical Informatics. - 1386-5056 .- 1872-8243. ; 65:2, s. 135-143
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Tidskriftsartikel (refereegranskat)abstract
- Objective: To investigate necessary conditions for the establishment of a database of diseases and health problems for research and health care planning, based on electronic patient records in everyday clinical use among general practitioners (GPs). Design: Postal questionnaire study. Setting: Primary health care in Sweden. Subjects: Three hundred randomly selected GPs. Main outcome measures: Degree of computerisation of patient records. User frequency and characteristics of diagnosis classification systems and coding tools. Frequency of coding activities and retrieval of codes, and related attitudes. Opinions on a primary health care version of ICD-10. Results: A total of 184 GPs (61% of the 300 GPs) were included in the study. About 92% used an electronic record system, some type of diagnostic classification was used by 93%, and ICD based classifications by 88%. The classification in use was computerised for 74%. Mainly simple tools were used to retrieve diagnostic codes. About 76% of GPs reported classifying at least one symptom or disease per encounter. The codes were retrieved 'once a month' or more by 19%. Classification of diseases was considered important for follow-up by 83%, and for the care of the patient by 75% of the GPs. The primary health care version of ICD-10 with a total of 972 codes was considered too limited in size by 31%. Conclusion: Electronic patient records in everyday clinical use in Swedish general practice provide several fundamentals for a database of diagnostic data. However, there are several barriers to the establishment of such a database that is both valid and reliable. ⌐ 2002 Elsevier Science Ireland Ltd. All rights reserved.
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| 6. |
- Qatarneh, Sharif M., et al.
(författare)
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Evaluation of a segmentation procedure to delineate organs for use in construction of a radiation therapy planning atlas
- 2003
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Ingår i: International Journal of Medical Informatics. - 1386-5056 .- 1872-8243. ; 69, s. 39-55
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: This paper evaluates a semi-automatic segmentation procedure to enhance utilizing atlas based treatment plans. For this application, it is crucial to provide a collection of 'reference' organs, restorable from the atlas so that they closely match those of the current patient. To enable assembling representative organs, we developed a semiautomatic procedure using an active contour method. Method: The 3D organ volume was identified by defining contours on individual slices. The initial organ contours were matched to patient volume data sets and then superimposed on them. These starting contours were then adjusted and refined to rapidly find the organ outline of the given patient. Performance was evaluated by contouring organs of different size, shape complexity, and proximity to surrounding structures. We used representative organs defined on CT volumes obtained from 12 patients and compared the resulting outlines to those drawn by a radiologist. Results: A strong correlation was found between the area measures of the delineated liver (r = 0.992), lung (r = 0.996) and spinal cord (r = 0.81), obtained by both segmentation techniques. A paired Student's t-test showed no statistical difference between the two techniques regarding the liver and spinal cord (p > 0.05). Conclusion: This method could be used to form 'standard' organs, which would form part of a whole body atlas (WBA) database for radiation treatment plans as well as to match atlas organs to new patient data.
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| 7. |
- Ölvingson, Christina, et al.
(författare)
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Using the critical incident technique to define a minimal data set for requirements elicitation in public health
- 2002
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Ingår i: International Journal of Medical Informatics. - 1386-5056 .- 1872-8243. ; 68:1-3, s. 165-174
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Tidskriftsartikel (refereegranskat)abstract
- The introduction of computer-based information systems (ISs) in public health provides enhanced possibilities for service improvements and hence also for improvement of the population's health. Not least, new communication systems can help in the socialization and integration process needed between the different professions and geographical regions. Therefore, development of ISs that truly support public health practices require that technical, cognitive, and social issues be taken into consideration. A notable problem is to capture ‘voices’ of all potential users, i.e., the viewpoints of different public health practitioners. Failing to capture these voices will result in inefficient or even useless systems. The aim of this study is to develop a minimal data set for capturing users' voices on problems experienced by public health professionals in their daily work and opinions about how these problems can be solved. The issues of concern thus captured can be used both as the basis for formulating the requirements of ISs for public health professionals and to create an understanding of the use context. Further, the data can help in directing the design to the features most important for the users.
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| 8. |
- Børøsund, Elin, et al.
(författare)
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Nurses' experiences of using an interactive tailored patient assessment tool one year past implementation
- 2013
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Ingår i: International Journal of Medical Informatics. - : Elsevier. - 1386-5056 .- 1872-8243. ; 83:7, s. E23-E34
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Despite evidence of benefits, integration of patient-centered communication in clinical practice is challenging. Interactive tailored patient assessment (ITPA) tools can contribute to a more patient-centered care approach. However, little research has examined the impact of such tools on nursing care once they have been implemented.OBJECTIVE: To explore nurses' experiences of the benefits of and barriers to using an ITPA called Choice, in cancer care one year after its implementation.METHODS: This investigation is a part of a larger study examining the use of Choice in cancer care. Four focus group interviews were conducted with 20 nurses experienced in using the Choice application. The data were analyzed using qualitative content analysis.RESULTS: Three themes and nine sub-themes emerged: (1) "Choice as facilitator for shared understanding and engagement in patients' own care," with three sub-themes: preparing both patient and nurse for communication, shared engagement in care planning, and giving the patients a voice; (2) "enhancing the patients' strengths," with two sub-themes: releasing patient's internal strengths and confirming "normalcy" for the patient; and (3) "new challenges for the nurse," with four sub-themes: organizational challenges, interactions with technology, a need for training in communication skills, and new ethical challenges.CONCLUSIONS: Findings suggest that, from nurses' perspectives, integration of ITPAs such as Choice in clinical practice offers many benefits that can contribute to patient-centered care. However, to reap these benefits, use of such tools must receive equal priority as other routines, and require sufficient time, space and competence. Choice also challenged nurses' professional roles and created dilemmas such as nurses' ambivalence regarding patients' levels of disclosure of sensitive issues and the nurses' ability to respond to them. Although patient-centered care is advocated as model for good clinical practice, this is not always internalized. Tools such as Choice may help to make such a shift happen.
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| 9. |
- Adolfsson, Eva Thors, et al.
(författare)
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Reporting systems, reporting rates and completeness of data reported from primary healthcare to a Swedish quality register : The National Diabetes Register
- 2011
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Ingår i: International Journal of Medical Informatics. - : Elsevier BV. - 1386-5056 .- 1872-8243. ; 80:9, s. 663-668
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Tidskriftsartikel (refereegranskat)abstract
- Objective:The aims of this paper were to study the reporting rate and completeness of data reported from primary healthcare centres (PHCCs) in Sweden to the Swedish National Diabetes Register (NDR), with a special attention on the relation between these measures and the reporting system used by the PHCCs.Method:A national survey conducted in Swedish primary healthcare covering the year 2006. A questionnaire was used to collect data from 523 PHCCs. Data on 87,099 adult diabetic patients attending these PHCCs and reported to the NDR were obtained from the register. In Sweden, participation in the NDR is voluntary. The data were reported through the Internet, either online using a web-based system or by direct transmission. The main outcome measures were reporting rate and completeness of reported data.Results:Of the 523 PHCCs, almost two-thirds had reported <75% of their diabetic patients to the NDR. The lowest reporting rate was found among the largest PHCCs, while the highest was found among small PHCCs (p < 0.001). Reasons given for not reporting data to the NDR were lack of time and lack of personnel resources. Altogether, 73.1% of the PHCCs reported data to the NDR online using a web-based system, 20.5% used direct transmission and 6.3% used both systems. The PHCCs that reported data through direct transmission systems reported almost 70% of their diabetic patients to the NDR, while PHCCs using web-based systems reported 54% of their diabetic patients to the NDR. Adjusted for other factors, using direct transmission increased the reporting rate by 13.0 percentage points. However, the web-based system contributed to a higher completeness of data than the direct transmission system.Conclusions:A direct transmission system facilitates a high reporting rate to the register at the expense of lower completeness of the reported data.
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