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PubMed2005

[The modified Brooker classification for evaluation of heterotopic ossifications in total hip replacement].

INTRODUCTION: To evaluate heterotopic ossifications (HTO) in total hip replacement several classifications have been developed. Most often the classifications according to Brooker or Arcq are used. These systems enable the description of HTO on x-rays in ap view, functional aspects like range of motion are not evaluated. In several studies we could observe that patients with HTO IV degrees according to Brooker ("ankylosis") had a free or excellent range of motion. We introduce a modified Brooker classification system which enables the evaluation of HTO in two X-ray planes and allows in addition a description of hip function. PATIENTS AND METHOD: On the a.-p. X-ray view the original Brooker classification is used, on the lateral view the Brooker classification ventrally and dorsally of the longitudinal axis of the stem of the total hip replacement is used. In addition functional deficits as a sequalae of HTO are documented (1: yes; 2: no). The new classification system is used in 10 cases with HTO IV degrees according to Brooker in the a.-p .view. RESULTS: 8 cases with "ankylosis" according to Brooker showed a good range of motion. In these cases HTO I-III degrees according to Brooker were found in the lateral view. In the ap view these HTO were evaluated as HTO IV degrees because of an overlapping effect. DISCUSSION: The new classification using X-rays in two planes allows to describe HTO sufficiently especially in respect to hip function. The most important advantage of this new classification is the fact that it modifies only a widly used and accepted system. This may lead to a high acceptance of the new classification.

Ankylosis↗

PubMed1998

World Health Organization Classification of lymphomas: a work in progress.

The World Health Organization (WHO) publishes classification handbooks for all neoplastic diseases. The last WHO Classification of leukemias and lymphomas was published in 1976. Since that time, through cytogenetics and molecular biology, it has been shown that many hematopoietic neoplasms are associated with a unique genetic profile. Similarly, the development of widely available and routinely applied monoclonal antibodies has allowed the identification of a unique immunophenotypic profile for most leukemias and lymphomas. These techniques have permitted the recognition of a number of distinct disease entities, and also enhance both diagnostic accuracy and reproducibility. The WHO Classification has been developed under the joint auspices of the European Association for Hematopathology (EAHP) and the Society for Hematopathology (SH). First organized in 1995, the Steering Committee appointed 10 committees covering T-cell and B-cell lymphomas and leukemias, myeloid and histiocytic tumors. The committees were asked to develop a list of diseases within their topic area, and to establish definitions of each disease according to established criteria. The WHO Classification uses the principles of the R.E.A.L. Classification, which defines each disease according to its morphology, immunophenotype, genetic features, postulated normal counterpart, and clinical features. Morphologic and clinical variants of individual diseases are discussed in the text, and their use is optional. The proposed classification was presented at the USCAP meeting in 1997, the site of the first joint meeting of the EAHP and SH. The presentation was followed by an open forum attended by EAHP and SH members. The Steering Committee also appointed a Clinical Advisory Committee to ensure that the classification meets clinical needs, and to resolve questions of clinical significance. The proposed WHO Classification for lymphomas is similar to the R.E.A.L. Classification for lymphomas, with minor modifications and reassessment of provisional categories based on new data since 1994.

B-Lymphocytes↗

PubMed2006

Interobserver reproducibility and application of the ISN/RPS classification of lupus nephritis-a UK-wide study.

We sought to assess the interobserver variation of the new International Society of Nephrology/Renal Pathology Society (ISN/RPS) classification of lupus nephritis when compared with the previous World Health Organization classification, when used by pathologists throughout the UK. We also sought differences in how the 2 classifications were applied to a single set of biopsies. Twenty unselected renal biopsies showing lupus nephritis were circulated to pathologists in the UK National Renal Pathology External Quality Assessment Scheme, before the ISN/RPS scheme was published, with a request to apply the World Health Organization classification. The same slides were recirculated approximately 1 year later with a request to apply the ISN/RPS classification. A significant improvement in interobserver reproducibility was demonstrated by the new classification (kappa 0.53 vs. 0.44, P = 0.002). The reproducibility of the assessment of disease activity and chronicity remains suboptimal (kappa = 0.33). The new classification tends to produce more diagnoses of Class IV lupus nephritis, with fewer diagnoses of Classes III and V. The improvement in interobserver reproducibility indicates that an important aim of the new classification has been achieved. Further work is needed to determine whether the increase in diagnosis of Class IV nephritis represents an improvement in biopsy interpretation or a divergence from the previous classification, as the latter could undermine attempts to relate results from the new system to treatment strategies based on clinical trials which used the old.

Humans↗

PubMed1992

Guidelines for developing, evaluating, and revising the classification of personality disorders.

The authors suggest ways to improve the classification of personality disorders by changing the way the classification is developed, evaluated, and modified. Specific proposals are intended to establish a system that can be evaluated and revised so that it successively approximates a valid system. The importance of stating the principles underlying the classification is emphasized. These principles include: the conception of personality disorder underlying each diagnosis, the structure used to define diagnoses, the nature of diagnostic items, and the model for organizing diagnostic decisions. A distinction is drawn among the theoretical, measurement, and diagnostic models underlying each diagnosis. The substantive aspects of the classification are discussed in terms of the evidence required to validate diagnostic concepts. It is argued that the first step in developing a classification is to ensure the content validity of diagnostic concepts because this is a prerequisite for other components of validity. Evaluation and revision of the classification are discussed in terms of the importance of convergent and discriminant evidence. It is recommended that the classification be evaluated and revised using criteria derived from the theoretical and measurement models associated with each diagnosis. It is also recommended that the classification be evaluated in terms of the degree to which diagnostic constructs are consistent across clinicians, different sets of diagnostic exemplars, and different samples of patients. Realization of these aims should provide a classification that may be verified, modified, or disproved in the scientific tradition.

Guidelines as Topic↗

PubMed1994

Occupational disability due to low back pain: a new interdisciplinary classification based on a phase model of disability.

STUDY DESIGN: This study critically reviewed current conceptualizations of occupational disability resulting from low back pain (LBP). It proposes a new classification system for back pain built on a phase-model of disability. OBJECTIVES: The goal was to develop a classification system that overcomes the shortcomings of existing classification schemes and is useful for interdisciplinary research, prevention, treatment, and rehabilitation. SUMMARY OF BACKGROUND DATA: Attempts to study and prevent disability resulting from LBP have been hampered by the use of inadequate classifications of LBP. METHODS: Current classifications of LBP were critically reviewed, and criteria for a useful classification system are described. The disabling process is organized in eight consecutive phases determined by the presence and duration of work disability. RESULTS: The proposed eight-phase classification is based primarily on the presence and duration of work-disability rather than on clinical categories. It takes into account the developmental and social character of disability. The simplicity, reliability, and expandability of the model allow for its interdisciplinary use in research and intervention. CONCLUSIONS: The prevention of disabling back pain requires an interdisciplinary approach. For this purpose, other than purely biomedical classifications of LBP are needed. The authors propose an eight-phase classification system primarily based on the duration of work disability and that takes into account other biomedical, developmental, and social characteristics of work-disability resulting from LBP.

Adult↗

PubMed2003

The impact of the garden classification on proposed operative treatment.

The current study evaluates the interobserver reliability and intraobserver reproducibility of the Garden classification of femoral neck fractures, assesses the influence of a lateral radiograph on a fracture's classification, and determines the classification's impact on the surgeon's choice of operative treatment. Forty radiographs of femoral neck fractures were evaluated independently by five orthopaedic surgeons. Kappa values were calculated for interobserver reliability and intraobserver variability with respect to the readers' ability to assess the fractures using the Garden classification and to determine fracture displacement with and without access to a lateral radiograph. In 69% of the instances in which a reader changed the classification of a fracture, the proposed treatment of the fracture did not change. The Garden classification has poor interobserver reliability but good intraobserver reproducibility. The addition of a lateral radiograph does not seem to improve the reliability of the current Garden classification system but may improve the reader's ability to determine fracture displacement. To improve the reliability and usefulness of the Garden classification, the authors suggest that the classification should be modified to have only two stages (Garden A-nondisplaced or valgus impacted and Garden B-displaced) and to include the use of a lateral radiograph.

Adult↗

PubMed2005

WHO/EORTC classification of cutaneous lymphomas 2005: histological and molecular aspects.

UNLABELLED: The new WHO/EORTC classification for cutaneous lymphomas comprises mature T-cell and natural killer (NK)-cell neoplasms, mature B-cell neoplasms, and immature hematopoietic malignancies. It reflects the unique features of lymphoproliferative diseases of the skin, and at the same time it is as compatible as possible with the concepts underlying the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. This article reviews the histological, phenotypical, and molecular genetic features of the various nosological entities included in this new classification. These findings always have to be interpreted in the context of the clinical features and biologic behavior. AIM: To review the histological, phenotypical and molecular genetic features of the various nosological entities of the new WHO/EORTC classification for cutaneous lymphomas. METHODS: Extensive review of the literature cited in Medline and own data of the authors. RESULTS: The WHO/EORTC classification of cutaneous lymphomas comprises mature T-cell and NK-cell neoplasms, mature B-cell neoplasms and immature hematopoietic malignancies. It reflects the unique features of primary cutaneous lymphoproliferative diseases. CONCLUSION: This classification is as much as possible compatible with the concept of the WHO classification for nodal lymphomas and the EORTC classification of cutaneous lymphomas. The histological, phenotypical and molecular genetic features always have to be interpreted in the context of the clinical features and biologic behavior.

Europe↗

PubMedDate not supplied

Validation of the classification of migraine without aura (IHS A1.1) proposed in ICHD-2.

OBJECTIVE: This study attempts to validate the alternative criteria for classification of migraine without aura (International Headache Society [IHS] A1.1) proposed in the appendix of The International Classification of Headache Disorders, 2nd edition. This method uses at least two of the associated symptoms (nausea, vomiting, photophobia, phonophobia, and osmophobia) in category D of the IHS classification. BACKGROUND: In the appendix of The International Classification of Headache Disorders, 2nd edition, an alternative method of classification of migraine without aura is proposed. This method of classification has never been validated. METHODS: A total of 1480 consecutive headache patients in a tertiary care setting were evaluated at first visit. Headache-associated features, such as intensity, lifetime duration, frequency per month, duration, triggers, prodrome, percentage recurrence, and postdrome frequency, were recorded. In addition, medication satisfaction, acute and monthly disability, grading of headache days, sleep normality, mood, and habits were documented. RESULTS: Of the 1480 patients, 901 were initially classified as having migraine IHS 1.1. Using the proposed alternative method (IHS A1.1), 885 (98.2%) of these patients were reclassified as having migraine. The remaining 16 (1.8%) patients not classified had only nausea and none of the other specified associated symptoms. They also exhibited different characteristics from the IHS migraine population as a whole regarding their headache and other features. CONCLUSIONS: This classification of migraine in a headache center population shows that the proposed use of any two of nausea, vomiting, photophobia, phonophobia, and osmophobia in category D of the classification may be a valid alternative method of classification. This study also demonstrates that the standard IHS methodology includes a very small group of patients who appear to be different from other migraine patients.

Adolescent↗

PubMed2006

Report of the ILAE classification core group.

A Core Group of the Task Force on Classification and Terminology has evaluated the lists of epileptic seizure types and epilepsy syndromes approved by the General Assembly in Buenos Aires in 2001, and considered possible alternative systems of classification. No new classification has as yet been proposed. Because the 1981 classification of epileptic seizure types, and the 1989 classification of epilepsy syndromes and epilepsies are generally accepted and workable, they will not be discarded unless, and until, clearly better classifications have been devised, although periodic modifications to the current classifications may be suggested. At this time, however, the Core Group has focused on establishing scientifically rigorous criteria for identification of specific epileptic seizure types and specific epilepsy syndromes as unique diagnostic entities, and is considering an evidence-based approach. The short-term goal is to present a list of seizure types and syndromes to the ILAE Executive Committee for approval as testable working hypotheses, subject to verification, falsification, and revision. This report represents completion of this work. If sufficient evidence subsequently becomes available to disprove any hypothesis, the seizure type or syndrome will be reevaluated and revised or discarded, with Executive Committee approval. The recognition of specific seizure types and syndromes, as well as any change in classification of seizure types and syndromes, therefore, will continue to be an ongoing dynamic process. A major purpose of this approach is to identify research necessary to clarify remaining issues of uncertainty, and to pave the way for new classifications.

Adolescent↗

PubMed2005

[Experiences with the new American Joint Committee on Cancer (AJCC) classification of cutaneous melanoma].

A new AJCC/UICC staging classification of malignant melanoma was published in 2001 and has been in use since then. Compared to the TNM classification used for the previous 15 years, the new classification contains fundamental changes. The classification of the primary tumor is now based on newly defined classes for Breslow's tumor thickness (0 - 1.0 mm; 1.01 - 2.0 mm, 2.01 - 4.0 mm; > 4.0 mm). Histopathologically diagnosed ulceration is the second prognostic factor in primary melanoma and its presence leads to upstaging into the next higher T category. Clark level of invasion is now only relevant for tumors up to 1 mm thick; levels IV and V are also reasons for upstaging. Classification of regional lymph node metastasis distinguishes between microscopic metastasis only as detected with sentinel lymph node biopsy and clinically detectable macroscopic metastasis. Additionally, the number of metastatic nodes and the presence of satellite and in-transit metastasis are prognostic factors for classification of regional lymph node metastasis. In distant metastasis, the kind of organ involvement has a role for classification (only skin and lymph nodes vs. lung vs. other organs) and an elevated LDH value leads to upstaging. A critical analysis of data of the German Central Malignant Melanoma Registry did not confirm the strong role of histopathological ulceration of the primary tumor in all T- and N-stages. Furthermore, there is an inconsistency of the classification as stage IIC displays a significantly worse prognosis as compared to stage IIIA. In spite of these drawbacks the new staging classification should used particularly in clinical trials in order to make data internationally comparable.

Germany↗

PubMed2004

Computer-aided diagnosis scheme for histological classification of clustered microcalcifications on magnification mammograms.

The histological classification of clustered microcalcifications on mammograms can be difficult, and thus often require biopsy or follow-up. Our purpose in this study was to develop a computer-aided diagnosis scheme for identifying the histological classification of clustered microcalcifications on magnification mammograms in order to assist the radiologists' interpretation as a "second opinion." Our database consisted of 58 magnification mammograms, which included 35 malignant clustered microcalcifications (9 invasive carcinomas, 12 noninvasive carcinomas of the comedo type, and 14 noninvasive carcinomas of the noncomedo type) and 23 benign clustered microcalcifications (17 mastopathies and 6 fibroadenomas). The histological classifications of all clustered microcalcifications were proved by pathologic diagnosis. The clustered microcalcifications were first segmented by use of a novel filter bank and a thresholding technique. Five objective features on clustered microcalcifications were determined by taking into account subjective features that experienced the radiologists commonly use to identify possible histological classifications. The Bayes decision rule with five objective features was employed for distinguishing between five histological classifications. The classification accuracies for distinguishing between three malignant histological classifications were 77.8% (7/9) for invasive carcinoma, 75.0% (9/12) for noninvasive carcinoma of the comedo type, and 92.9% (13/14) for noninvasive carcinoma of the noncomedo type. The classification accuracies for distinguishing between two benign histological classifications were 94.1% (16/17) for mastopathy, and 100.0% (6/6) for fibroadenoma. This computerized method would be useful in assisting radiologists in their assessments of clustered microcalcifications.

Algorithms↗

PubMed2001

Application of classification tree and neural network algorithms to the identification of serological liver marker profiles for the diagnosis of hepatocellular carcinoma.

OBJECTIVE: Although many attempts have been made to identify tumour-specific alpha-fetoprotein (AFP) glycoforms or other serological markers for the diagnosis of hepatocellular carcinoma (HCC), none of the available markers has, so far, shown satisfactory sensitivity and specificity. Here we aimed to apply classification tree and neural network algorithms to interpret the levels of multiple serological liver markers to improve overall specificity and sensitivity, particularly with a view to discriminating between liver cirrhosis with and without HCC. METHODS: We developed classification trees and neural networks that identified serological liver marker profiles comprising AFP, alpha1-antitrypsin (A1AT), alpha2-macroglobulin (A2MG), thyroxine-binding globulin (TBG), transferrin and albumin as well as sex and age, which might permit the diagnosis of HCC. Data were collected from 65 HCC patients, 51 patients with liver cirrhosis alone (LC) and 51 normal healthy subjects. RESULTS: The generated classification trees and neural networks showed similar diagnostic values in differentiating HCC from LC. The classification trees identified AFP, A1AT and albumin as the most important classification parameters, whereas the neural networks identified A2MG, AFP, A1AT and albumin as the predominant factors. The classification logic of the classification trees indicated that more HCC cases could be identified among cases with slightly elevated AFP levels by using the serum levels of A1AT and albumin. The neural networks were also useful for the identification of the HCC cases when the AFP levels were below 500 ng/ml (p < 0.005). The neural networks could identify HCC cases with AFP levels within the normal range, but the classification trees could not. By combining the conventional AFP test and the neural networks, the overall diagnostic sensitivity for HCC was significantly increased from 60.0 to 73.8% (p < 0.05) while maintaining a high specificity (88.2%). The sensitivities for tumors of different sizes were similar. CONCLUSION: The neural network algorithm appeared to be more powerful than the classification tree algorithm in the identification of the distinctive serological liver marker profiles for the diagnosis of the HCC subgroup without significant elevation in serum AFP levels. By incorporating serological levels of other liver markers and including data from a large number of patients and control subjects, it should prove possible to develop a versatile neural network for early diagnosis of HCC.

Adult↗

PubMed2006

Revision of visual impairment definitions in the International Statistical Classification of Diseases.

BACKGROUND: The existing definitions of visual impairment in the International Statistical Classification of Diseases are based on recommendations made over 30 years ago. New data and knowledge related to visual impairment that have accumulated over this period suggest that these definitions need to be revised. DISCUSSION: Three major issues need to be addressed in the revision of these definitions. First, the existing definitions are based on best-corrected visual acuity, which exclude uncorrected refractive error as a cause of visual impairment, leading to substantial underestimation of the total visual impairment burden by about 38%. Second, the cut-off level of visual impairment to define blindness in the International Statistical Classification of Diseases is visual acuity less than 3/60 in the better eye, but with increasing human development the visual acuity requirements are also increasing, suggesting that a level less than 6/60 be used to define blindness. Third, the International Statistical Classification of Diseases uses the term 'low vision' for visual impairment level less than blindness, which causes confusion with the common use of this term for uncorrectable vision requiring aids or rehabilitation, suggesting that alternative terms such as moderate and mild visual impairment would be more appropriate for visual impairment less severe than blindness. We propose a revision of the definitions of visual impairment in the International Statistical Classification of Diseases that addresses these three issues. According to these revised definitions, the number of blind persons in the world defined as presenting visual acuity less than 6/60 in the better eye would be about 57 million as compared with the World Health Organization estimate of 37 million using the existing International Statistical Classification of Diseases definition of best-corrected visual acuity less than 3/60 in the better eye, and the number of persons in the world with moderate visual impairment defined as presenting visual acuity less than 6/18 to 6/60 in the better eye would be about 202 million as compared with the World Health Organization estimate of 124 million persons with low vision defined as best-corrected visual acuity less than 6/18 to 3/60 in the better eye. CONCLUSION: Our suggested revision of the visual impairment definitions in the International Statistical Classification of Diseases takes into account advances in the understanding of visual impairment. This revised classification seems more appropriate for estimating and tracking visual impairment in the countries and regions of the world than the existing classification in the International Statistical Classification of Diseases.

Biometry↗

PubMed2003

Estrogen receptor classification for hepatocellular carcinoma: comparison with clinical staging systems.

PURPOSE: Several scoring systems to evaluate patients with hepatocellular carcinoma (HCC) exist. A good scoring system should provide information on prognosis and guide therapeutic decisions. The presence of variant liver estrogen receptor (ER) transcripts in the tumor has been shown to be the strongest negative predictor of survival in HCC. The aim of this study was to compare the predictive value of the commonly applied clinical scoring systems for survival of patients with HCC with that of the evaluation of ER in patients with HCC (molecular scoring system). MATERIALS AND METHODS: HCC was staged according to the Okuda classification, Barcelona Clinic Liver Cancer classification, Italian classification system (CLIP), French classification, and ER status in 96 patients. Analysis of survival was performed according to the Kaplan-Maier test and was made for each classification system and ER. A comparison between classifications was made by univariate and multivariate analysis. RESULTS: Among the clinical classification systems, only the CLIP was able to identify patient populations with good, intermediate, and poor prognosis. On multivariate analysis, ER classification was shown to be the best predictive classification for survival of patients with HCC (P <.0001). This difference was the result of a better allocation of patients with ominous prognosis (variant ER) having nevertheless good clinical score. CONCLUSION: The evaluation of the presence of wild-type or variant ER transcripts in the tumor is the best predictor of survival in patients with HCC. Its accuracy in discriminating patients with good or unfavorable prognosis is significantly greater than that of the commonly used scoring systems for the staging of HCC.

Adult↗

PubMed2004

Drug-related problem classification systems.

OBJECTIVE: To provide an overview of and critically appraise classifications of drug-related problems (DRPs) for use during the pharmaceutical care process and research in pharmacy. DATA SOURCES: A literature search was conducted using MEDLINE and Yahoo (January 2003) and manually. The search terms included DRP, drug-related problem, drug-therapy problem, and medicine-related problem. STUDY SELECTION AND DATA EXTRACTION: English- and German-language articles on pharmaceutical care and DRPs were reviewed. DATA SYNTHESIS: Most classifications of DRPs were identified through searching publications on pharmaceutical care and DRPs. Fourteen classifications with different focuses were found. Some classifications were hierarchical, categorized into main groups and subgroups. Various terminologies and definitions for DRPs were revealed, as well as guidelines for an optimal DRP classification. Classifications were assessed according to a clear definition, published validation method, and results reflecting process and outcomes, usability in pharmaceutical care practice, and a hierarchical structure with main groups and subgroups. CONCLUSIONS: Finding DRP classifications by computerized search of the biomedical literature with the help of PubMed proved to be difficult. No classification could be found that met all of our criteria for an optimal system. Few classifications have been validated. Three have been tested as to their usability in practice and internal consistency. The Pharmaceutical Care Network Europe system Version 4 comes closest to the defined requirements.

Drug-Related Side Effects and Adverse Reactions↗

PubMed1997

Clinical classification of periodontitis in adolescents and young adults.

THE AIM OF THIS STUDY was to determine the degree to which clinical classifications based on cross-sectional assessments endure in the course of development of early-onset periodontitis (EOP), and to introduce new criteria which might improve the clinical classification of these diseases. Subjects with EOP and a matched group without EOP were identified within a national probability sample examined during the 1986/87 survey of US schoolchildren. Of these, 265 subjects (mean age 16 years) were re-examined during the 1992/93 school year. The clinical attachment level of teeth was assessed, and the individuals were classified into localized juvenile periodontitis (LJP), generalized juvenile periodontitis (GJP), incidental attachment loss (IAL), and no-periodontitis groups using three classification methods previously described. A fourth method that considered the extent and severity of attachment loss and the number of missing teeth was introduced to classify the individuals at baseline and at follow-up as having localized, generalized, or incidental EOP, and no-periodontitis groups. Furthermore, the individuals were classified using criteria based on the rate and pattern of change in attachment loss during 6 years. The results showed low correlations between the baseline classifications and the classifications at the 6-year follow-up examination, irrespective of the method used. In addition, the cross-sectional classifications were not predictive of the rate of progression of periodontal disease in these subjects. In the generalized disease group, two-thirds of the individuals exhibited moderate/rapid disease progression, while one-third had slow or no progression. In the localized disease group, one-half of the individuals had moderate/rapid disease progression and one-half had slow or no progression. In the incidental disease group one-fourth of the individuals had moderate/rapid disease progression and three-fourths had slow or no progression. We propose that the term early-onset periodontitis be used as a generic term to describe periodontal disease before its normal onset. In addition, we suggest that incidental, localized, and generalized EOP are heterogenous groups comprising rapidly and slowly progressing forms within each classification. The findings suggest that a classification system in which subsets of the disease that are defined according to a combination of cross-sectional criteria and the disease progression may be useful in studies of EOP. Furthermore, the findings suggest that clinical classifications of EOP be used as generic descriptors until a full understanding of the pathogenesis of this disease is accomplished.

Adolescent↗

PubMed2006

Reliability and reproducibility of dens fracture classification with use of plain radiography and reformatted computer-aided tomography.

BACKGROUND: The classification system of dens fractures by Anderson and D'Alonzo has been widely used in clinical studies. Of the three types of fractures, Type II and Type III are of particular importance because the distinction between them may affect treatment decisions. The purposes of this study were to assess whether this classification is reliable and reproducible and to determine whether computed tomography can improve its reliability and reproducibility. METHODS: Plain radiographs and spiral computed tomography images of dens fractures in eleven patients were assessed, and the fractures were assigned a classification of Type II or Type III at two readings, separated by six months, by two spine surgeons and three neuroradiologists. Kappa coefficients of agreement between the raters as well as the reproducibility of the classifications made by the individual raters were calculated independently for the fracture classifications based on the plain radiographs and those based on the reformatted computed tomography scans. RESULTS: The kappa coefficient for classifications based on plain radiographs was 0.30 and 0.25 (fair agreement) at the first and second readings, respectively. For classifications based on computed tomography scans, the corresponding kappa coefficients were 0.46 (moderate agreement) and 0.67 (substantial agreement). The kappa coefficients for intrarater reliability among the five raters averaged 0.56 (moderate agreement) when computed tomography scans were used and 0.28 (fair agreement) when plain radiographs were used. CONCLUSIONS: Substantial variation with regard to the classification of dens fractures was found within our group of raters. Greater agreement occurred when reformatted computed tomography scans rather than plain radiographs were used as the basis for classification. When classifying dens fractures according to the system of Anderson and D'Alonzo, one should consider using reformatted computed tomography scans and reaching a consensus with multiple raters.

Adolescent↗

PubMed2003

Repetition priming mediated by task similarity in semantic classification.

In the present study, the specificity of repetition priming between semantic classification tasks was examined using Osgood's (Osgood, Suci, & Tannenbaum, 1957) semantic space as a heuristic for determining the similarity between classifications. The classification tasks involved judging the meaning of words on semantic scales, such as pleasant/unpleasant. The amount of priming across classifications was hypothesized to decrease with increasing distance (decreasing similarity) between semantic scales in connotative semantic space. The results showed maximum repetition priming when the study and the test classifications were the same, intermediate degrees of priming when the study and the test classification scales shared loadings on semantic factors, and little priming when the study and the test classification scales loaded primarily on orthogonal semantic factors--that is, when the distance between scales was maximized. Consistent with the transfer-appropriate processing framework, repetition priming in semantic classifications was highly task specific, decreasing with increasing distance between classification scales.

Attention↗