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PubMed2004

Categorizing patients with occupational low back pain by use of the Quebec Task Force Classification system versus pain pattern classification procedures: discriminant and predictive validity.

BACKGROUND AND PURPOSE: Quebec Task Force Classification (QTFC) and pain pattern classification (PPC) procedures, including centralization and noncentralization, are common classification procedures. Classification was done to estimate validity of data obtained with QTFC and PPC procedures for differentiating patient subgroups at intake and for use in predicting rehabilitation outcomes at discharge and work status at 1 year after discharge from rehabilitation. SUBJECTS: Patients (n=171, 54% male; mean age=37 years, SD=10, range=18-62) with acute work-related low back pain referred for physical therapy were analyzed. METHODS: Patients completed pain and psychosocial questionnaires at initial examination and discharge and pain diagrams throughout intervention. Physical therapists classified patients using QTFC and PPC data at intake. Patients were classified again at discharge by PPC (time-dependent PPC). RESULTS: Analysis of variance of showed QTFC and PPC data could be used to differentiate patients by pain intensity or disability at intake. Analysis of covariance showed that intake PPC predicted pain intensity and disability at discharge, but QTFC did not. Logistic regression showed that PPC predicted work status at 1 year, but QTFC did not. Classifying patients over time using time-dependent PPC data reduced the false positive rate by 31% and increased percentage of change in pretest-posttest probability of return to work by 16% compared with classifying patients at intake. DISCUSSION AND CONCLUSION: Results support the discriminant validity of the QTFC data at intake and predictive validity of the PPC data at intake. Tracking PPC over time increases predictive validity for 1-year work status.

Acute Disease↗
PubMed1991

Classification of lung cancer: first experiences with the new TNM classification (4th edition).

In January 1987, the 4th edition of the TNM classification for malignant lung tumours by the International Union Cancer (UICC) came into effect. Thus, for the first time, a uniform worldwide staging system for lung cancer became available. In order to validate the new TNM definitions for lung cancer the data of 3,000 patients were analysed prospectively. Several items were examined: 1) the agreement between clinically (TNM) and pathologically (pTNM) confirmed classification; 2) the value of the various diagnostic techniques estimating the pathologically confirmed classification; 3) the influence of the TNM definitions on separating distinct prognostic groups. With regard to the primary tumour (T), clinical and pathological classifications were identical in 64%; for lymph node involvement (N) the agreement was 48%; for distant metastases it was 90% and for the stages it was 55%. As for the primary tumour (T) the accuracy of radiography (59%) was nearly identical to computed tomography (58%). Both techniques were less precise in determining the extent of lymph node involvement (computed tomography 50%, radiography 43%, correct assessments). The statistically significant differences in prognosis for the various T-, N- and M-categories as well as for the stages could be confirmed. By the new 1987 TNM definitions (4th edition) for lung cancer international conformity became feasible as well as practical, and the improvement in its prognostic relevance provided, therefore, a more reliable basis for establishing guidelines for individual oncological concepts of therapy.

Carcinoma, Bronchogenic↗
PubMed1983

[Malignant ventricular hyperkinetic arrhythmias. Classificational criteria: review of Lown's classification. Polycentric study].

Although Lown grading system of ventricular premature complexes (VPCs) has important conceptual shortcomings and has shown severe limitations in either cross-sectional or longitudinal studies, this classification is still the most well-known and used method to characterize the arrhythmologic ventricular pattern of the individual patient. We have looked at a modification of VPCs Lown grading scheme to correct the defects and to make the use of the classification more accurate. Our proposal is based on maintenance of 5 classes--similar to those of Lown original classification--to which we have assigned a score from 0 to 60. We have also introduced many sub-classes, each with a definite score, to better characterize the type of arrhythmic event. The sum of the score of the highest class and the score of every subclass furnishes the final score. This score is a direct index of the importance of the ventricular arrhythmias and seems to be useful for statistical evaluation of the anti-arrhythmic therapy and for follow-up studies, as confirmed by preliminary clinical results obtained through the use of this new VPCs classification.

Arrhythmias, Cardiac↗
PubMed1982

The classification of anxiety and hysterical states. Part II. Toward a more heuristic classification.

In the historical review and empirical delineation of the classification of anxiety and hysterical states (Part I), it was concluded that the existing classifications are unsatisfactory and require some reconceptualization if they are to be useful clinically and empirically. In keeping with more recent developments in the genetic, behavioral, pharmacological, biochemical, and psychophysiological investigation of these disorders, a new classification is proposed. The two major categories of anxiety and hysterical disorders have a different clinical presentation and course, a different mean age of onset, distribution of age of onset, sex distribution, response to treatment modalities, and habituation response on galvanic skin response. Empirical evidence supporting this proposal is cited. This classification has heuristic merit in guiding research efforts and discussions and in directing clinicians to a simple and practical solution to their patients' anxiety disorders.

Adult↗
PubMed1994

[The new international psychiatric classification system, ICD-10. II. New classification systems in psychiatry].

The different interpretations of the concept of "mental disease" and the absence of an etiopathogenetic plane in the area of mental disorders led to the creation of descriptive (phenomenological) classifications of mental disorders. Their main representatives are the American diagnostic and statistical manual of mental disorders, DSM-III, its revised version DSM-III-R and the new international classification of mental disorders iCD-10. Both systems use a common theoretical baseline and are to a considerable extent compatible. Typically they have a high reliability and low validity of diagnostic categories. Subsequent development of psychiatric classifications will be focused in particular on improvement of diagnostic validity. The international psychiatric classification was created in different versions for the purpose of specialized psychiatric care, primary care and for research.

Humans↗
PubMed1997

A clinical evaluation of the International Lymphoma Study Group classification of non-Hodgkin's lymphoma. The Non-Hodgkin's Lymphoma Classification Project.

The recognition of several new types of non-Hodgkin's lymphoma (NHL) in recent years has led to proposals for changing lymphoma classifications, including a new proposal put forth by the International Lymphoma Study Group (ILSG). However, the clinical significance of the new entities and the practical utility of this new proposal have not been studied. Therefore, we performed a clinical evaluation of the ILSG classification. A cohort of 1,403 cases of NHL was organized at nine study sites around the world and consisted of consecutive patients seen between 1988 and 1990 who were previously untreated. A detailed protocol for histologic and clinical analysis was followed at each site, and immunologic characterization as to T- or B-cell phenotype was required. Five expert hematopathologists visited the sites and each classified each case using the ILSG classification. A consensus diagnosis was also reached in each case, and each expert rereviewed a 20% random sample of the cases. Clinical correlations and survival analyses were then performed. A diagnosis of NHL was confirmed in 1,378 (98.2%) of the cases. The most common lymphoma types were diffuse large B-cell lymphoma (31%) and follicular lymphoma (22%), whereas the new entities comprised 21% of the cases. Diagnostic accuracy was at least 85% for most of the major lymphoma types, and reproducibility of the diagnosis was 85%. Immunophenotyping improved the diagnostic accuracy by 10% to 45% for a number of the major types. The clinical features of the new entities were distinctive. Both the histologic types and the patient characteristics as defined by the International Prognostic Index predicted for patient survival. In conclusion we found that the ILSG classification can be readily applied and identifies clinically distinctive types of NHL. However, for clinical application, prognostic factors as defined by the International Prognostic Index must be combined with the histologic diagnosis for appropriate clinical decisions.

Adult↗
PubMed1998

[Severity of glomerular damage with IgA nephropathy and renal prognosis: a comparison between pattern classification and calculated classification].

In our laboratory, a semi-quantitative pattern classification (PC) for the distribution pattern of glomerular sclerotic lesions in biopsied renal specimens with IgA nephropathy has been utilized, and found to be quite beneficial for predicting the patient's prognosis. In the present study conducted to re-evaluate this classification, 503 patients with IgA nephropathy (male/female, 256/247; mean age: 32.1 +/- 13.5 yrs; follow-up: 9.3 +/- 4.5 yrs) were used. The patients had been divided originally into 5 groups based on a previous PC: minimal, mild, moderate, severe and advanced groups. Their glomerular lesions were classified as mild, moderate, severe and global sclerosis, and were given scores of 1-4 points. The mean glomerular score was then calculated for each patient, as a value of the calculated classification (CC), and all patients were then re-divided into 5 groups based on their scores. The renal survival curves in the CC were similar to those in PC, and no significant differences in the renal survival rates were found between the classifications in each group, thus suggesting that the CC has a similar predictive power for renal survival. Although 7 of 39 cases (18%) with global sclerosis in PC groups 4 and 5 shifted down to CC group 3, of 61 patients with global sclerosis in PC group 1 who had a good prognosis, 26 cases (43%) shifted up to the CC group 2 and 6 cases (8%) changed to the CC group 3. As a result, the predictive power in patients in the lower CC groups was lost for the renal survival rate. In conclusion, statistical comparison between the PC and CC groups revealed that global sclerosis presents in non/minimally affected glomeruli as a nonspecific alteration. Severely advanced cases also possess a high incidence of globally sclerotic glomeruli (87%), and therefore the occurrence of global sclerosis may involve two different pathogenic mechanisms.

Adolescent↗
PubMed1998

Concept-oriented standardization and statistics-oriented classification: continuing the classification versus nomenclature controversy.

Nowadays, most activities on controlled medical vocabularies focus on the provision of a sufficient atomic-level granularity for representing clinical data. Amongst others, clinical vocabularies should be concept oriented, compositional and should also reject "Not Elsewhere Classified". We strongly share the opinion that there is a need to deal with serious deficits of existing manually created vocabularies and with new demands for computer-based advanced processing and exchange of medical language data. However, we do not share the opinion that methodological requirements like observational and structural comparability needed for sound statistics should not be included in desiderata of controlled medical vocabularies. Statistical-oriented classifications are not developed for representing detailed clinical data but for providing purpose-dependent classes where cases of interest are assigned uniquely. Either statistical classifications are not included into the set of controlled medical vocabularies in the sense of Cimino, or his desiderata are misleading. We argue that statistical classifications should be linked to (formal) concept systems, but again this linkage does not change their different natures. With this article we continue the "classification versus nomenclature" controversy referring to Coté.

Data Interpretation, Statistical↗
PubMedDate not supplied

Automatic classification of biomedical information when classification error is unknown.

This paper describes a distribution-free method for the automatic classification of individuals by phenotype of the serum protein alpha 1-antitrypsin. This method achieved 74 per cent agreement and a Kappa value of 0.24 when compared to the conventional classification procedure on an independent testing sample. The methodology is appropriate for many classification problems, particularly when the true classes and the reliability of the conventional procedure are unknown.

Classification↗
PubMed2000

Validation of a new method for patient classification, the Oulu Patient Classification.

At Vasa Central Hospital in Western Finland a further development of the Oulu Patient Classification (OPC) has been made by the development of weight coefficients and by estimating the nursing care intensity per nurse. The daily level of nursing care intensity of a ward is expressed by the number of nursing care intensity points per nurse. This article presents results from a validity test of the OPC at Vasa Central Hospital. The test was carried out by comparing the daily patient classifications by means of the OPC against measurements made by means of a new measuring instrument, the 'Professional Assessment of Optimal Nursing Care Intensity Level' (PAONCIL) developed at the Vasa Central Hospital. The study was implemented in eight wards during a period of 3 months. The data material consisted of two parts, the daily patient classifications based on the OPC (n = 19 324) and the measurements by means of the PAONCIL forms (n = 8458). Simple and multiple linear regression analyses were used as statistical methods in quantifying the linear relationship between the two interval-scaled variables. In the test of concurrent validity the coefficient of determination was 0.366, i.e. the association between these two indicators is fairly strong (36.6%). The testing of construct validity showed that the construct validity of the indicator hardly deteriorates as a result of the patients being placed in separate nursing care intensity categories. There was a clear correlation between the scores allotted by the indicator to the six different sub-areas of nursing care. When examining the construct validity of the OPC, no factors with independent explanatory power in predicting PAONCIL values were discovered other than those of the OPC. The OPC proved on the basis of this research material and these statistical methods to possess fairly adequate validity, and thus there is a good basis for further research and a development of nursing care.

Analysis of Variance↗
PubMed1984

An international classification of retinopathy of prematurity. The Committee for the Classification of Retinopathy of Prematurity.

Because of modern life-support systems capable of keeping tiny premature infants alive, retinopathy of prematurity has recurred. No classification system currently available adequately describes the observations of the disease being made today. A new classification system, the work of 23 ophthalmologists from 11 countries, is presented in an attempt to meet this need. It emphasizes the location and the extent of the disease in the retina as well as its stages. The term "plus" is employed with the stage to denote progressive vascular incompetence. A computer-compatible diagram for recording the results of the examination employing the new classification system is furnished.

Humans↗
PubMed1983

A new working formulation of non-Hodgkin's lymphomas. A retrospective study of the new NCI classification proposal in comparison to the Rappaport and Kiel classifications.

Two hundred thirty cases of malignant non-Hodgkin's lymphomas were reclassified in a retrospective study according to the New Working Formulation for Clinical Usage of the NCI as compared to the Rappaport and Kiel classifications. The reproducibility for the individual schemes this study was 81% (Rappaport), 79% (Kiel), and 85% (New Working Formulation). In keeping with the results of the NCI international study, all lymphomas were subdivided into 3 prognostic groups: (1) low-grade malignancy (6.0 years median survival); (2) intermediate-grade malignancy (3.5 years median survival); and (3) high-grade malignancy (1.4 years median survival). The NCI-proposed New Working Formulation for Clinical Usage is thus recommended as practical and unprejudicing classification scheme for general application; however, its usefulness as tool for translating one classification scheme into another appears limited.

Europe↗
PubMed1986

Development of criteria for the classification and reporting of osteoarthritis. Classification of osteoarthritis of the knee. Diagnostic and Therapeutic Criteria Committee of the American Rheumatism Association.

For the purposes of classification, it should be specified whether osteoarthritis (OA) of the knee is of unknown origin (idiopathic, primary) or is related to a known medical condition or event (secondary). Clinical criteria for the classification of idiopathic OA of the knee were developed through a multicenter study group. Comparison diagnoses included rheumatoid arthritis and other painful conditions of the knee, exclusive of referred or para-articular pain. Variables from the medical history, physical examination, laboratory tests, and radiographs were used to develop sets of criteria that serve different investigative purposes. In contrast to prior criteria, these proposed criteria utilize classification trees, or algorithms.

Adult↗
PubMed1996

Clinical and cytofunctional classification of pituitary adenomas: proposal of a new classification.

Recent methodological advances in immunohistochemistry, ultrastructural techniques, hormonal assays, resolution imaging and molecular biology techniques have provided new insights into the pathology, function and cytogenesis of pituitary adenomas. Pituitary adenomas have been classified historically on the basis of tinctorial affinities, followed by the basis of ultrastructure and immunohistochemistry. The current development of technologies necessitate the new classification of pituitary adenomas which integrates these numerous parameters as well as the clinical manifestations. For this purpose, we suggest a new clinico-cytofunctional classification of pituitary adenomas, which is based on these clinical manifestations and integrates the information on biology, imaging function and ultrastructure. This classification which corresponds to current advances will not only provide pertinent clinical data but facilitate better understanding of the biology and nature of these complexed lesions.

Adenoma↗
PubMed2004

Classification of orally administered drugs on the World Health Organization Model list of Essential Medicines according to the biopharmaceutics classification system.

Since its inception in 1995, the biopharmaceutical classification system (BCS) has become an increasingly important tool for regulation of drug products world-wide. Until now, application of the BCS has been partially hindered by the lack of a freely available and accurate database summarising solubility and permeability characteristics of drug substances. In this report, orally administered drugs on the Model list of Essential Medicines of the World Health Organization (WHO) are assigned BCS classifications on the basis of data available in the public domain. Of the 130 orally administered drugs on the WHO list, 61 could be classified with certainty. Twenty-one (84%) of these belong to class I (highly soluble, highly permeable), 10 (17%) to class II (poorly soluble, highly permeable), 24 (39%) to class III (highly soluble, poorly permeable) and 6 (10%) to class IV (poorly soluble, poorly permeable). A further 28 drugs could be provisionally assigned, while for 41 drugs insufficient or conflicting data precluded assignment to a specific BCS class. A total of 32 class I drugs (either certain or provisional classification) were identified. These drugs can be further considered for biowaiver status (drug product approval based on dissolution tests rather than bioequivalence studies in humans).

Administration, Oral↗
PubMed2000

[Morphologic classification of hypertrophic cardiomyopathy with myocardial single photon emission tomography. Comparison with echocardiographic classification].

INTRODUCTION AND OBJECTIVES: The aim of this study was to compare different morphologic types of hypertrophic cardiomyopathy obtained by single photon emission tomography to those obtained by echocardiogram. MATERIALS AND METHODS: In 76 (64%) out of 119 patients with hypertrophic cardiomyopathy the echocardiogram permitted an optimal visualization of all left ventricular segments in the short axis view and consequent classification to one of the six morphological types: type I (septal anterior hypertrophy), type II (septal anterior and septal posterior hypertrophy), type III (septal and antero-lateral hypertrophy), type IV (antero-lateral and/or septal posterior hypertrophy), type V (concentric hypertrophy) and type VI (apical hypertrophy). Without knowledge of echo data, two experienced observers included the short axis of single photon emission tomography images at rest (99mTc-tetrofosmin) to one of those types. RESULTS: Global concordance between echocardiogram and single photon emission tomography was 75%. Type III was the most frequent both in echo (76%) and in single photon emission tomography (74%) and type III produced the majority of discrepancies. SPET identified 4 patients with a predominant septal and inferior hypertrophy, that did not correspond to any of the 6 types of echocardiographic classification and had been previously classified as type III by echo in 3 cases and as type V in 1 case. CONCLUSIONS: There was agreement between echo and single photon emission tomography in the morphological classification of most of the patients (75%) with hypertrophic cardiomyopathy. Nevertheless, some discrepancies were observed for the type III echocardiogram.

Cardiomyopathy, Hypertrophic↗
PubMed1992

Revision of classification of laryngeal cancer, is it long overdue? (Proposals for an improved TN-classification).

The TNM-classification of laryngeal carcinomas of the UICC contains a number of weaknesses which diminish their prognostic relevance. Based on clinical observations and microscopic investigations of surgical specimens, several changes are proposed to improve the existing TN-classification. The larynx is subdivided by the UICC into the supraglottic, the glottic and the subglottic main area and their tumours. There are embryological, anatomical, functional and oncological reasons to divide the larynx into two main areas only--the supraglottis and the glottis (vocal folds) without any further subsites and to abandon a separate group of subglottic tumours. The T size of a tumour should not be assessed according to the extent of an ill-defined anatomical region, but measured in millimetres of greatest surface extent only. The T2 category of vocal fold tumours should not contain those which lead to an inhibited mobility of the fold. All tumours with reduced vocal fold mobility or fixation should be classified as T3 or T4 according to the dimension of invasion. Post-operative pathological examinations (pT/pN) allow an assessment of the true extent of a tumour in three dimensions. A validation study using a 'metric' TpT-classification shows very distinct groups of tumours with a significantly different prognosis from Tis 1 to T4. Studies of lymph node metastases in the neck have shown that, number, size, site of metastasis and the presence of extracapsular tumour spread have a significant influence on the prognosis. An improved N/pN-classification taking these factors in consideration is proposed.

Carcinoma in Situ↗
PubMed2000

New classification of haemodynamics of vasovagal syncope: beyond the VASIS classification. Analysis of the pre-syncopal phase of the tilt test without and with nitroglycerin challenge. Vasovagal Syncope International Study.

We believe that the pattern of blood pressure response to tilt during the time preceding the development of the vasovagal reaction may provide adjunctive diagnostic information. A group of 101 consecutive patients affected by syncope of uncertain origin underwent passive tilt testing for 45 min at 60 degrees followed, if negative, by oral (sublingual) trinitroglycerin (TNG) 0.4 microg with continuation of the test for 20 min. Three main patterns were observed: the classic (vasovagal) syncope pattern was observed in 36 patients who, during the preparatory phase, had a rapid and full compensatory reflex adaptation to upright position, resulting in stabilization of their blood pressure values until abrupt onset of the vasovagal reaction; the dysautonomic (vasovagal) syncope pattern was observed in 47 patients in whom steady-state adaptation to upright position was not possible. There was thus a progressive fall in their blood pressure until the occurrence of a typical vasovagal reaction; the orthostatic intolerance pattern was observed in 18 patients in whom there was a progressive fall in blood pressure, similar to that of the dysautonomic group, but this was not followed by a clear vasovagal reaction. Compared with the classic, the dysautonomic patients were older, had a higher prevalence of co-morbidities, a very much shorter history of syncopal episodes, and a prevalence of mixed and vasodepressor forms of the VASIS classification. The patients with orthostatic intolerance had clinical characteristics similar to the dysautonmic group but they could not be classified according to the VASIS classification. In conclusion, in patients with syncope, a variety of abnormal responses is observed during tilt testing, suggesting that different syndromes can be diagnosed by the test. A more detailed, although still arbitrary, classification may form the basis of a number of future drug and pacemaker trials, as well as help towards a greater understanding of the different mechanisms of tilt-induced syncope.

Autonomic Nervous System↗