Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CLASSIFICATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55Linked to original sources
PubMed2006

Testing a classification model for emergency department errors.

AIM: This paper presents an evaluation of the Eindhoven Classification Model for categorizing healthcare errors. BACKGROUND: The ability to decrease healthcare errors will depend on an understanding of the types and patterns of error that occur in various settings. Research addressing the systematic classification of error is in its infancy. METHODS: The sample for this study was two existing sets of healthcare error reports obtained from the emergency department of a regional trauma center. Study data were collected in the summer of 2001 and 2002. The errors in these reports were categorized using a coding tool based on the Eindhoven Classification Model. In addition to testing for inter-rater reliability, the classification model was also evaluated for the number of unclassifiable errors and of categories never selected by the raters (not useful to the error classification model). RESULTS: Our findings of poor inter-rater reliability, large numbers of unclassifiable errors and categories not selected, suggest that the Eindhoven Classification Model, in its current form, cannot be applied to categorizing healthcare errors in an emergency department setting. CONCLUSIONS: Further study is needed to develop and test error categorization models for use in emergency departments and other healthcare settings.

Causality↗
PubMed1997

A survey of the ASA physical status classification: significant variation in allocation among Finnish anaesthesiologists.

BACKGROUND: The American Society of Anesthesiologists' (ASA) Classification of Physical Health is a widely used grading system for preoperative health of the surgical patient. In previous studies conducted in North America and Great Britain, considerable variation in the ASA classification allocation has been reported. We hypothesised that in smaller and culturally more homogeneous countries there might be less variation in the ASA classification. METHODS: A postal questionnaire depicting 10 hypothetical patient cases was sent to 249 randomly selected members of the Finnish Society of Anaesthesiologists. Responses of anaesthesiologists working in university teaching and non-teaching hospitals were compared, as well as the answers of specialists and non-specialists. RESULTS: Responses were received from 108 anaesthesiologists (response rate 43%). There was marked variation in the classification of all the 10 cases: 1 case was classified to all five possible grades (ASA grades I-V). In 2 cases, there was significant variation between anaesthesiologists working in university teaching and non-teaching hospitals. There was no difference in the grading between specialist and non-specialist anaesthesiologists. CONCLUSION: In a small and culturally homogeneous country, like Finland, there exists similar wide variation in the ASA classification as has been previously reported from larger and culturally more heterogeneous countries. The significant variation should always be considered when using this classification in clinical or scientific work.

Adult↗
PubMed1994

Dimensional strategies dominate perceptual classification.

The nature of perceptual classification was investigated in children ranging between 4 and 10 years, and in young adults. Triad classification task responses were categorized as consistent or inconsistent with several classification rules, including: overall-similarity, size-dimensional, brightness-dimensional, pure identity, and all combinations of a switch from one rule to another midway through the experiment. The rule with the highest proportion of responses consistent with it reflected each person's best-fitting rule pattern. The higher this value, the higher the assumed consistency of rule usage. Data from the majority of individuals in every age group conformed best to one of the three dimensional rules. In addition, the consistency values for individuals' best-fitting rule became significantly higher as age increased. It is concluded that most children have a tendency to attend selectively to one stimulus dimension when making perceptual classification judgments. The developmental trend in perceptual classification does not appear to be a holistic-to-analytic shift; instead, it is a trend toward greater consistency in following a given classification rule.

Adult↗
PubMed1997

Mothers' representations of their infants assessed prenatally: stability and association with infants' attachment classifications.

The stability and predictive validity of classifications of mothers' representations of their infants as determined by the Working Model of the Child Interview (WMCI) were examined. Concordance between mothers' representations of their infants assessed prenatally and again one year later and infant Strange Situation (SS) attachment classifications at 12 months was also examined. WMCI classifications were stable over 12 months in 80% of mothers, compared to 51% expected by chance alone. Pregnancy WMCIs predicted infant SS classifications in 74% of cases, compared to 54% expected by chance. Concordance between 11-month WMCI and 12-months SS classifications was 73% (vs. 55% expected by chance). Problems with the skewed distribution of the sample, the low concordance between pregnancy and 11 months for one of the three classifications, and future directions for research are discussed.

Female↗
PubMed2005

Definition and classification of chronic kidney disease: a position statement from Kidney Disease: Improving Global Outcomes (KDIGO).

Chronic kidney disease (CKD) is a worldwide public health problem, with adverse outcomes of kidney failure, cardiovascular disease (CVD), and premature death. A simple definition and classification of kidney disease is necessary for international development and implementation of clinical practice guidelines. Kidney Disease: Improving Global Outcomes (KDIGO) conducted a survey and sponsored a controversies conference to (1) provide a clear understanding to both the nephrology and nonnephrology communities of the evidence base for the definition and classification recommended by Kidney Disease Quality Outcome Initiative (K/DOQI), (2) develop global consensus for the adoption of a simple definition and classification system, and (3) identify a collaborative research agenda and plan that would improve the evidence base and facilitate implementation of the definition and classification of CKD. The K/DOQI definition and classification were accepted, with clarifications. CKD is defined as kidney damage or glomerular filtration rate (GFR) <60 mL/min/1.73 m(2) for 3 months or more, irrespective of cause. Kidney damage in many kidney diseases can be ascertained by the presence of albuminuria, defined as albumin-to-creatinine ratio >30 mg/g in two of three spot urine specimens. GFR can be estimated from calibrated serum creatinine and estimating equations, such as the Modification of Diet in Renal Disease (MDRD) Study equation or the Cockcroft-Gault formula. Kidney disease severity is classified into five stages according to the level of GFR. Kidney disease treatment by dialysis and transplantation should be noted. Simple, uniform classifications of CKD by cause and by risks for kidney disease progression and CVD should be developed.

Albuminuria↗
PubMed1984

Concepts of lymphoma classification.

Three major classification schemes for malignant non-Hodgkin's lymphomas are widely applied today: Rappaport's classification, the Kiel classification, and the New Working Formulation for Clinical Usage. All three classifications define prognostically relevant lymphoma entities yet can only partly be translated one into the other. This is because morphologically defined lymphomas still include certain inhomogeneic entities, which again applies to all three classifications. It is therefore strongly suggested that supplemented morphologic methods of lymphoma classification be by immunologic and cytochemical investigations to improve on the scientific definition of malignant lymphomas and also to obtain the most solid basis for therapeutic planning.

Humans↗
PubMed2004

Clinical classification of bioengineered skin use and its correlation with healing of diabetic and venous ulcers.

BACKGROUND: Chronic wounds are being treated with bioengineering skin constructs. Yet, there is no standard way of assessing these wounds. We developed a classification system to evaluate wounds after construct application. The classification system evaluates the early clinical effect of bioengineered skin and early construct appearance giving a total score named the skin substitute score. OBJECTIVE: Apply classification system to both venous and diabetic foot ulcers and determine whether classification system has validity and predictability for healing. METHODS: Evaluated serial photographs in 83 and 78 patients with diabetic foot ulcers and in 84 and 83 patients with venous ulcer on Days 7 and 14, respectively, treated with a bilayered bioengineered skin construct. Applied the classification system and determined the percentages of healed patients. RESULTS: There was a significant correlation between better skin substitute score and complete wound closure for both venous ulcers p=0.002 on Day 7 and p=0.01 on Day 14) and diabetic foot ulcers p=0.0005 on Day 7 and p<0.0001 on Day 14). CONCLUSION: Optimal clinical effect was associated with complete wound closure. As the clinical effect becomes less than optimal continued clinical persistence of the construct becomes important. This classification system seems to have validity in predicting complete wound closure in wounds treated with a bilayered bioengineered skin construct.

Adolescent↗
PubMed2005

The effect of insomnia definitions, terminology, and classifications on clinical practice.

There is a need for newer, more clinically useful classifications for insomnia. Identification of specific subtypes of insomnia helps anchor research, allows for prediction of prognosis/course of the condition, and may allow for individualization of treatment. Existing classifications differ, and many terms remain inadequately defined, which leads to diagnostic confusion. Historically, insomnia has been classified according to symptom type, symptom duration, and underlying cause, but these classifications have not been based on evidence of their utility, and newer research suggests the need for change. Symptoms may include difficulty falling asleep, trouble staying asleep, and not feeling restored by sleep, although it has not been clear that it is possible to identify distinct subtypes of patients by symptom or that distinguishing symptom type affects the course of clinical treatment. Classification of insomnia by duration most commonly involves three categories: transient (no more than a few days), short-term (up to 3 weeks), and long-term (more than 3 weeks). This categorization is of uncertain utility and has been primarily based on nonempiric concerns about treatment with sedative-hypnotic medications for periods longer than several weeks. The subtyping of insomnia in terms of whether there is an identifiable underlying cause such as a psychiatric or medical illness was based on an unproven assumption that in most instances other disorders caused insomnia. Recent studies suggest the need to revisit these classification strategies. Evidence that symptom types typically overlap and change over time complicates the categorization of subjects by whether they have difficulty falling asleep or staying asleep or have nonrestorative sleep. New studies of the treatment of chronic insomnia change the perspective on duration of treatment and, as a result, classification of duration of disease. Two studies of nightly pharmacotherapy for insomnia including more than 800 insomnia patients have not identified any increase in the risks after 3 to 4 weeks of treatment. In addition, nonpharmacological treatments demonstrate long-lasting efficacy in patients with chronic insomnia, and the development of abbreviated cognitive-behavioral therapies, which are particularly well suited to primary care practice, have improved their applicability. Newer studies of the relationships between insomnia and associated medical and psychiatric conditions undermine the notion that insomnia is always a symptom and caused by an underlying condition. They suggest that, although it is important to identify and treat these conditions, this may not be sufficient to alleviate the insomnia, which may adversely affect the course of the associated disorder. As a result, treatment targeted specifically to the insomnia should be considered. All of these developments point to an increasing ability to tailor therapy to the particular needs of patients and to optimize the clinical management of insomnia.

Humans↗
PubMed1996

Nursing intervention classification systems.

PURPOSE: To analyze the features, development, and research of the Omaha System, the Iowa Nursing Intervention Classification, and the Home Health Care Classification and provide a critical review of the unique components of each. ORGANIZING FRAMEWORK: Five elements: achievement of original purpose, language used, ease of computerizing format, clinical utility, and linkage of the Nursing Minimum Data set (NMDS) nursing care elements. CONCLUSIONS: Further testing and development of nursing classification systems should be done to determine the general value of nursing classification, the extent to which the original goals and purposes of classification are met, and to identify the unique features and contributions of each system. Further testing is important to determine the strengths, weaknesses, and applicability of the various systems for capturing the elements of the NMDS for different care settings, care givers, and patient populations. IMPLICATIONS: Nursing classification may eventually lead to naming and describing the work of nurses. Research findings will continue to provide information leading to a unified nursing language system that describes the practice of nursing in local, regional, national, and international health-care data sets used for research, clinical, education, policy, and administrative purposes.

Community Health Nursing↗
PubMed1999

Classification of ocular atopic/allergic disorders and conditions: an unsolved problem.

PURPOSE: To review the different classifications of ocular allergic diseases and to define the most suitable one according to the current understanding of the pathophysiology and clinical course of these disorders. METHODS: Review of the major published ocular allergy classifications. RESULTS: Based on past and present classifications, the author proposes the following classification: 1. allergic conjunctivitis (acute and chronic); 2. giant papillary conjunctivitis; 3. vernal keratoconjunctivitis; and 4. atopic keratoconjunctivitis. In addition, use of the term "allergic conjunctivitis" as a synonym for all ocular allergic disease is discouraged. CONCLUSION: The proposed classification for ocular allergic disorders intends to unify the present criteria and to serve as an initial forum of discussion. This should enhance a common understanding among and between ophthalmologists and other allergy specialists. Constructive criticism of this classification system is required for further improvement.

Conjunctivitis, Allergic↗
PubMed1978

Clinico-pathological correlations in the Kiel classification of non-Hodgkin's lymphomata in children.

The rapid development of chemotherapy and radiotherapy during the last decade makes an increasing demand for a reliable classification of malignant non-Hodgkin's lymphomas. This is especially important in children since in this age group the lymphomas show a much worse prognosis than in adults. An attempt at a modern classification is offered by the so-called Kiel classification. 38 children with non-Hodgkin's lymphomas previously classified according to Rappaport were re-evaluated according to the Kiel system. Reclassification was technically feasible in 26 patients. There was good agreement on typing between the two independently working cytopathologists. 3 patients proved to be cases of histiocytic medullary reticulosis. Among the remaining patients, a much larger variety of histological subgroups was seen than in the one published paediatric series of Lennert. 17 patients had high-grade malignant lymphomas with lymphoblastic lymphomas predominating. Some clinical correlations not detectable with the Rappaport classification were found using the Kiel system. 6 patients were judged as having low-grade malignant lymphomas but in this group the survival was poorer than expected and 1 patient showed leukaemic transformation. The Kiel classification makes high demands for adequate surgical techniques and preparatory routines. It seems to represent a step forward in the classification of non-Hodgkin's lymphomas but much more experience is needed, especially in children, in order to evaluate its role as a guide to differentiated therapy.

Child↗
PubMed2006

Classification of odontogenic tumours. A historical review.

Using the term odontome for any tumour arising from the dental formative tissues, Broca suggested a classification of odontogenic tumours (OTs) in 1869. From 1888 to 1914, Bland-Sutton and Gabell, James and Payne modified tumour terminology, while maintaining Broca's odontome concept. Thoma and Goldman's classification (1946) divided the OTs into tumours of ectodermal, mesodermal and mixed origin and abolished the general term odontome. The Pindborg and Clausen classification (1958) based on the idea that the reciprocal epithelial-mesenchymal tissue interactions were also operating in the pathogenesis of OTs. In 1966, WHO established a Collaborating Centre for the Histological Classification of Odontogenic Tumours and Allied Lesions (including jaw cysts) headed by Dr Jens Pindborg. In 1971, the first authoritative WHO guide to the classification of OTs and cysts appeared followed in 1992 by a second edition. In 2002, Philipsen and Reichart produced a revision of the 1992-edition and in 2003, the editors of the WHO Blue Book series: 'WHO Classification of Tumours' decided to produce a volume on the Head and Neck Tumours including a chapter on Odontogenic Tumours and Bone Related Lesions. In July of 2005 this volume was published by IARC, Lyon.

History, 19th Century↗
PubMed1983

A clinico-pathological and immunological study of unfavourable non-Hodgkin lymphomas. Comparison of the Rappaport and Kiel classifications.

To evaluate the prognostic information of the Kiel classification a homogeneous material of 63 non-Hodgkin lymphomas of unfavourable Rappaport histology were re-evaluated according to the definitions of the Kiel classification. The patients were selected from a prospective lymphoma study including 775 patients. Only ambiguous histological diagnoses analysed independently by two hematopathologists were accepted. Immunological markers of the tumours studied both in suspensions and on cryostate sections were in addition analysed in 40 of the patients. Forty-one per cent (26/63) were of high grade malignancy according to the Kiel classification, 59% (36/63) were of low-grade malignancy. The DLPD group was most heterogeneous while a better concordance was found between DM and CB/CC and between DH and CB cases. However, prognostic subgroups of the two classifications were only partly equivalent. A good correlation was found between the Kiel high-grade malignant group and patients of Rappaport poorest prognosis (DU, DH). Eighty-eight per cent of the lymphomas were of B cell, 5% of T cell and 7% of non-B-non-T phenotypes. Both the Kiel and Rappaport morphologic classifications predicted survival in this selected material. Patients with B phenotypes survived longer than patients with lymphomas of non-B type. Among patients with diffuse lymphomas, those with a nodular and irregular distribution of immunoglobulin and C3d receptors tended to respond better and survived longer. No prognostic information was obtained from immunoglobulin isotypes, C3d or Fc-gamma receptors. It is concluded that the Kiel classification is equally reliable for clinical judgement as the Rappaport system and that immunological marker studies may add prognostic information.

Adult↗
PubMedDate not supplied

A new classification system for dental treatment under general anesthesia.

The provision of comprehensive care for patients with special needs using dental general anesthesia (DGA) has changed over time, and now includes more complex procedures and the participation of many services. As a result, it is necessary to integrate, organize and describe all of the procedures that are carried out in different DGA settings. The aim of this study was to propose a systematic classification for dental treatment procedures be delivered under DGA, and to compare this classification system with an existing system. This new classification system has three distinct components: type, frequency and length of time needed to complete dental procedures for both primary and permanent teeth. A wide range of oral surgery procedures and endodontic treatment was also included. A retrospective cohort study utilizing 84 subjects was used to develop and compare the two classification systems. When comparing the different categories of procedures by both classifications, there were significant statistical differences between them (p < 0.05). Oral health care for patients with special needs has evolved, with more complex and extensive interventions that require teamwork by personnel from different dental or medical specialties. The classification system in this study includes detailed information regarding the procedures involved in the DGA. This helps to provide a clear understanding and specific information that enables the comparison of clinical experiences across populations where a DGA has been used for patients with special needs.

Adolescent↗
PubMed2000

Automated classification of clustered microcalcifications into malignant and benign types.

The objectives in this study were to design and test a fully automated method for classification of microcalcification clusters into malignant and benign types, and to compare the method's performance with that of radiologists. A novel aspect of the approach is that the relative location and orientation of clusters inside the breast was taken into account for feature calculation. Furthermore, correspondence of location of clusters in mediolateral oblique (MLO) and cranio-caudal (CC) views, was used in feature calculation and in final classification. Initially, microcalcifications were automatically detected by using a statistical method based on Bayesian techniques and a Markov random field model. To determine malignancy or benignancy of a cluster, a method based on two classification steps was developed. In the first step, classification of clusters was performed and in the second step a patient based classification was done. A total of 16 features was used in the study. To identify meaningful features, a feature selection was applied, using the area under the receiver operating characteristic (ROC) curve (Az value) as a criterion. For classification the k-nearest-neighbor method was used in a leave-one-patient-out procedure. A database of 192 mammograms with 280 true positive detected microcalcification clusters was used for evaluation of the method. The set consisted of cases that were selected for diagnostic work up during a 4 year period of screening in the Nijmegen region (The Netherlands). Because of the high positive predictive value in the screening program (50%), this set did not contain obvious benign cases. The method's best patient-based performance on this set corresponded with Az = 0.83, using nine features. A subset of the data set, containing mammograms from 90 patients, was used for comparing the computer results to radiologists' performance. Ten radiologists read these cases on a light-box and assessed the probability of malignancy for each patient. All participants had experience in clinical mammography and participated in our observer study during the last 2 days of a 2-week training session leading to screening mammography certification. Results on the subset showed that the method's performance (Az = 0.83) was considerably higher than that of the radiologists (Az = 0.63).

Breast Neoplasms↗
PubMed2005

Time-reversal imaging for classification of submerged elastic targets via Gibbs sampling and the Relevance Vector Machine.

Time-reversal imaging (TRI) is analogous to matched-field processing, although TRI is typically very wideband and is appropriate for subsequent target classification (in addition to localization). Time-reversal techniques, as applied to acoustic target classification, are highly sensitive to channel mismatch. Hence, it is crucial to estimate the channel parameters before time-reversal imaging is performed. The channel-parameter statistics are estimated here by applying a geoacoustic inversion technique based on Gibbs sampling. The maximum a posteriori (MAP) estimate of the channel parameters are then used to perform time-reversal imaging. Time-reversal implementation requires a fast forward model, implemented here by a normal-mode framework. In addition to imaging, extraction of features from the time-reversed images is explored, with these applied to subsequent target classification. The classification of time-reversed signatures is performed by the relevance vector machine (RVM). The efficacy of the technique is analyzed on simulated in-channel data generated by a free-field finite element method (FEM) code, in conjunction with a channel propagation model, wherein the final classification performance is demonstrated to be relatively insensitive to the associated channel parameters. The underlying theory of Gibbs sampling and TRI are presented along with the feature extraction and target classification via the RVM.

Journal Article↗
PubMed2006

Classification tree method for bacterial source tracking with antibiotic resistance analysis data.

Various statistical classification methods, including discriminant analysis, logistic regression, and cluster analysis, have been used with antibiotic resistance analysis (ARA) data to construct models for bacterial source tracking (BST). We applied the statistical method known as classification trees to build a model for BST for the Anacostia Watershed in Maryland. Classification trees have more flexibility than other statistical classification approaches based on standard statistical methods to accommodate complex interactions among ARA variables. This article describes the use of classification trees for BST and includes discussion of its principal parameters and features. Anacostia Watershed ARA data are used to illustrate the application of classification trees, and we report the BST results for the watershed.

Animals↗
PubMed2001

Behaviour of Crohn's disease according to the Vienna classification: changing pattern over the course of the disease.

BACKGROUND: Crohn's disease is a heterogeneous disorder with both a genetic and environmental aetiology. Clinical classifications of the disease, such as the newly proposed Vienna classification, may help to define subgroups of patients suitable for studying the influence of specific genetic or environmental factors. AIM: To assess the stability over the course of the disease of its location and behaviour, as determined according to the Vienna classification. PATIENTS AND METHODS: The notes of 297 Crohn's disease patients regularly followed up at our institution were carefully reviewed retrospectively. The behaviour and location of the disease according to the Vienna classification were determined at diagnosis and after 1, 3, 5, 10, 15, 20, and 25 years of follow up. The proportions of the different behaviours and locations of the disease were calculated at these time points. A statistical analysis of the evolution of these characteristics over 10 years was performed on a subgroup of 125 patients with at least 10 years of follow up. The influence of age at diagnosis on location and behaviour of the disease was assessed as well as the influence of location on the behaviour of the disease. RESULTS: The location of the disease remained relatively stable over the course of the disease. Although the proportion of patients who had a change in disease location became statistically significant after five years (p=0.01), over 10 years only 15.9% of patients had a change in location (p<0.001). We observed a more rapid and prominent change in disease behaviour, which was already statistically significant after one year (p=0.04). Over 10 years, 45.9% of patients had a change in disease behaviour (p<0.0001). The most prominent change was from non-stricturing non-penetrating disease to either stricturing (27.1%; p<0.0001) or penetrating (29.4%; p<0.0001) disease. Age at diagnosis had no influence on either location or behaviour of disease. Ileal Crohn's disease was more often stricturing, and colonic or ileocolonic Crohn's disease was more often penetrating: this was already the case at diagnosis and became more prominent after 10 years (p<0.05). CONCLUSIONS: Location of Crohn's disease, as defined by the Vienna classification, is a relatively stable phenotype which seems suitable for phenotype-genotype analyses. Behaviour of Crohn's disease according to the Vienna classification varies dramatically over the course of the disease and cannot be used in phenotype-genotype analyses. The potential influence of genes on the behaviour of Crohn's disease should be studied in subgroups of patients defined by their disease behaviour after a fixed duration of disease.

Adult↗