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PubMed1993

[How to recognize and classify male infertility].

Infertility of the couple affects 19% of the general population, 4% of which are infertile. Almost 50% of infertilities are ascribable to the male partner. Male infertility is determined by a preliminary clinical and biological evaluation which consists of full examination of the semen, with sperm and spermocyte counts and cultures. Further examinations depend on the data provided by this evaluation. The causes of human infertility can be classified as follows: 1. Abnormalities of the spermatozoa which may be of testicular origin (defect of gonadal maturation, genetic of genic congenital anomalies, varicocele) or of post-testicular origin (acquired or congenital excretory obstacle to be located by surgery and treated whenever possible. 2. Abnormalities of seminal plasma (seminal infections, autoimmunization, isoimmunization). 3. Abnormalities of ejaculation (pathogenic or iatrogenic retrograde ejaculation, organic or psychic anejaculation). 4. Unknown cause requiring more sophisticated sperm examinations, such as microvideography of the flagellum, exploration of the acrosome and of nuclear maturation.

Ejaculation↗
PubMed1995

A successful protocol for the use of pulse oximetry to classify arterial oxygenation into four fuzzy categories.

Pulse oximetry is widely used in critical care medicine to noninvasively estimate arterial hemoglobin oxygen saturation. Despite the obvious benefits of using pulse oximetry to detect life threatening desaturations, it is unknown how well pulse oximetry is able to predict the finer graduations of arterial oxygenation needed for clinical decision making. A computerized protocol was developed for the use of pulse oximetry to classify arterial oxygenation into four fuzzy categories and tested in a prospective clinical trial which compared the oxygenation category assigned by the protocol to one assigned by a respiratory therapist. In 3,742 classifications from 15 patients over a seven month period, the protocol showed 96% agreement with the therapists in the direction of therapy and 75% agreement with the oxygenation classes assigned by the therapists.

Clinical Protocols↗
PubMed1977

Classifying disease in general practice.

I have developed a system of classifying diseases in general practice based on headings relevant to general practice which are built up in a hierarchy. I believe this is better than abbreviating the International Classification of Disease with the addition of individual symptoms.Ideally, a classification ought to include occupational diseases and psychosocial problems, and it must be accompanied by a terminology defining as precisely as possible the different categories based on criteria relevant to ordinary general practice. It should still follow the main divisions of the International Classification of Disease as far as possible.I believe that general practice will not progress any further unless it is prepared to loosen its traditional allegiance to hospitalorientated disease classifications, which are, for our purpose, inappropriately rigid.

Disease↗
PubMed1977

A comparison of three systems of classifying presenting problems in general practice.

Three internationally recognized systems have been devised for classifying presenting problems in general practice. They are: the Royal College of General Practitioners' (1963) classification, the US Ambulatory Medical Care Classification of Symptoms (NAMCS), and the World Organization of Colleges and Academies of General Practice/Family Medicine (WONCA, 1976) classification which is known as An International Classification of Health Problems of Primary Care (ICHPPC).These three systems were compared in over 8,000 consultations conducted by 81 randomly selected British general practitioners in Nottinghamshire.For all ages of patient, the NAMCS, which has only 197 categories, was the most specific, and the least specific was the classification of the Royal College of General Practitioners.

Diagnosis↗
PubMed1995

Cytogenetic analysis of B cell chronic lymphoid leukemias classified according to morphologic and immunophenotypic (FAB) criteria.

609 patients with B cell chronic lymphoproliferative disorder were studied with the primary aim of analyzing the cytogenetic profile of B cell chronic lymphocytic leukemias and, if possible, define correlations with FAB classification of these diseases. Morphological and immunological studies were performed according to criteria proposed by the FAB group. A panel of monoclonal antibodies, including at least sIg, CD19, CD5, and FMC7 was used. Interpretations of morphology and cytogenetics were made independently. When applying strict FAB criteria 65% of the cases could be classified. Most of them (44%) were chronic lymphocytic leukemia (CLL). The cases not satisfying strict FAB criteria could be divided into two groups: one closely related to CLL, and here defined as atypical CLL (aCLL) (21%) and another group consisting of patients with leukemic manifestations of B cell non-Hodgkin's lymphoma (LL) (14%). Analyzable metaphases were obtained in 89% of patients. Clonal abnormalities were present in 35% of patients. The most frequent chromosomal changes were abnormalities of chromosome 11q (60 cases), trisomy 12 (46 cases) and structural rearrangements of chromosome 14q (44 cases). Statistical associations with FAB subtypes were found: aCLL and trisomy 12 (P < 0.00001); mantle zone lymphoma (MZL) and t(11;14) (P < 0.00001) and del(6)(q) (P < 0.0001); CLL/mixed cell type and del(6)(q) (P < 0.002); follicular lymphoma and t(14;18) (P < 0.00001); splenic lymphoma with villous lymphocytes and del(7)(q) (P < 0.0004); leukemic lymphoma (LL) with rearrangements in chromosome 9q (P < 0.0001) and trisomy of 3 (P < 0.001). Chronic lymphocytic leukemia was not statistically associated with any specific chromosomal abnormality. However, this subtype showed a high incidence of del(11)(q) and rearrangements of 13q. This study confirms the value of cytogenetic investigation in the diagnosis of these disorders and may provide some new elements for future refinement of the FAB classification in mature B cell lymphocytic disorders.

Chromosome Aberrations↗
PubMed1996

Mutation in and lack of expression of tyrosinase-related protein-1 (TRP-1) in melanocytes from an individual with brown oculocutaneous albinism: a new subtype of albinism classified as "OCA3".

Most types of human oculocutaneous albinism (OCA) result from mutations in the gene for tyrosinase (OCA1) or the P protein (OCA2), although other types of OCA have been described but have not been mapped to specific loci. Melanocytes were cultured from an African-American with OCA, who exhibited the phenotype of Brown OCA, and his normal fraternal twin. Melanocytes cultured from the patient with OCA and the normal twin appeared brown versus black, respectively. Melanocytes from both the patient with OCA and the normal twin demonstrated equal amounts of NP-40-soluble melanin; however, melanocytes from the patient with OCA contained only 7% of the amount of insoluble melanin found from the normal twin. Tyrosinase- related protein-1 (TRP-1) was not detected in the OCA melanocytes by use of various anti-TRP-1 probes. Furthermore, transcripts for TRP-1 were absent in cultured OCA melanocytes. The affected twin was homozygous for a single-bp deletion in exon 6, removing an A in codon 368 and leading to a premature stop at codon 384. Tyrosine hydroxylase activity of the OCA melanocytes was comparable to controls when assayed in cell lysates but was only 30% of controls when assayed in intact cells. We conclude that this mutation of the human TRP-1 gene affects its interaction with tyrosinase, resulting in dysregulation of tyrosinase activity, promotes the synthesis of brown versus black melanin, and is responsible for a third genetic type of OCA in humans, which we classify as "OCA3."

Albinism, Oculocutaneous↗
PubMed1996

Avascular necrosis and the Pavlik harness. The incidence of avascular necrosis in three types of congenital dislocation of the hip as classified by ultrasound.

We analysed the incidence of avascular necrosis in 101 hips of 90 infants with congenital dislocation treated with Pavlik harness and followed up for more than one year. Using ultrasonography in the flexed-abducted position the hips were classified as type A when the femora head was displaced posteriorly, but within the socket and making contact with the posterior inner wall of the acetabulum; type B when it was in contact with the posterior margin of the acetabulum, with its centre at this level or anterior to it; and type C when it was displaced out of the socket, with its centre posterior to the posterior rim of the acetabulum. Eighty-seven hips were reduced by the harness (86%), and seven of these developed avascular necrosis (8%). All 69 hips with type-A dislocation were reduced and only one (1.4%) showed slight avascular necrosis. Eighteen (78.3%) of 23 hips with type-B dislocation were reduced, and six developed avascular necrosis (33.3%). In one hip, the femoral head was severely damaged. None of the nine hips with type-C dislocation was reduced in the harness. We concluded that the Pavlik harness is indicated for type-A but not for type-B or type-C dislocations.

Contraindications↗
PubMed1996

The reliability of Marlatt's taxonomy for classifying relapses.

Marlatt's focus on the relapse situation has had a major impact upon research and clinical practice in treating addictions. One component of his work was the development of a taxonomy for classifying precipitants of relapse. This taxonomy has been incorporated into the nomenclature of clinicians and clinical researchers as part of an explanatory framework for understanding relapses. Despite the taxonomy's influence it has never been examined for the reliability of its use across research studies. The present study compared the reliability of independent classifications of 149 relapse episodes by trained raters at three research laboratories. Despite considerable across-laboratory training, reliability was found to be inconsistent for research purposes. It is concluded that comparability of results based on Marlatt's relapse taxonomy across independent studies must be subject to question, and assumptions necessary for the aggregation of a knowledge base are not supported. Recommendations are offered for improving the reliability of the taxonomy and the methods used to collect taxonomy data. More generally, questions regarding the value of the specific relapse categories, as well as the overall taxonomy, are raised.

Adult↗
PubMed1996

Classifying individuals among infra-specific taxa using microsatellite data and neural networks.

The method of neural networks was tested for its ability to assign individuals on the basis of their multilocus genotypes, using a data collection of 430 honeybees and 8 microsatellite loci. This data set includes various taxonomical levels (populations within the same subspecies, various subspecies belonging to the same evolutionary lineage, and the 3 lineages of the species). Qualitative genotypic data have been submitted to 2 types of transformation (simple coding and coding plus factorial correspondence analysis), and they have been partitioned in 2 sets, a training set of 300 individuals and a testing set of 103 individuals. Two procedures ("leave one out" and "hold out") were applied to evaluate the quality of prediction. Compared to discriminant analysis, neural networks performed better in terms of correctly classified individuals at any taxonomical level. For instance, with the simple coding and the hold out procedure, the proportions of correctly assigned individuals from the testing set were 66.2%, 82.3% and 100% at the populations, subspecies and lineage level, respectively. The potential use of neural networks in populations genetics is discussed.

Animals↗
PubMedDate not supplied

Tibioperoneal diaphyseal toxopachyosteosis or Weismann-Netter-Stuhl syndrome: difficulties encountered in classifying this syndrome and differentiation from rickets.

Using two new cases and 70 case reports in the literature as a starting point, the authors focus on the Weismann-Netter-Stuhl syndrome. Weismann-Netter and Stuhl reported the first cases of tibioperoneal diaphyseal toxopachyosteosis in 1954. This syndrome is defined as an anomaly of the diaphyseal part of both tibiae and fibulae with posterior cortical thickening and anterior-posterior bowing. This anomaly is usually bilateral and symmetrical, and patients are therefore short in stature. The thickening of the fibula is true "tibialisation" and "is the main feature and the only feature confirming diagnosis". Routine laboratory investigations showed no abnormalities in the two new cases. The authors specify the limits encountered in classifying this anomaly and discuss the degree to which this anomaly is an entity unto itself when compared with rickets sequelae.

Abnormalities, Multiple↗
PubMed1997

Reliability evaluation of classifying radial head fractures by the system of Mason.

Inter-observer and intra-observer reliability for classifying radial head fractures by the system of Mason was analyzed. Twenty-three cases of isolated radial head fractures and twenty-five sets of corresponding AP and lateral radiographs representing these fractures were assembled. The cases were reviewed and assessed independently according to the system of Mason by twenty practicing orthopedic surgeons. On two occasions, the inter-observer and intra-observer variation was analyzed by standard unweighted Kappa statistics. In both observations, complete agreement was seen in only 16% of the cases. Kappa statistic values indicated that 69% of the cases at first observation and 45% of the cases at second observation suggest moderate to poor agreement. Intra-observer agreement between the first and second observation was graded fair to poor in 60% of the cases. Individual observer consistency was, on average, only 78% (range 60% to 92%). The demonstrated wide degree of variation suggests that the Mason classification is unreliable.

Confidence Intervals↗
PubMed1998

[Criteria for classifying chemical substances according to toxicity: carcinogens, irritants, corrosives, allergens, fetotoxins and those absorbed through the skin].

The authors reviewed and presented the criteria used to classify the toxic effects of chemicals such as carcinogenic, irritation, corrosive, allergic, and fetotoxicity, as well as dermal absorption of chemical agents. The criteria for assigning symbols to the Polish list of chemical MAC values has not as yet been determined. Following the analysis it may be concluded that all chemical compounds, which satisfy the requirements should be indexed on the MAC list.

Allergens↗
PubMed1998

[Interobserver agreement on diagnoses classified according the International Classification of Primary Care].

OBJECTIVE: To measure interobserver agreement on diagnoses classified and coded by family physicians using manual or computerized input modes. METHOD: Used increasingly in a variety of information management systems, the International Classification of Primary Care is the system best adapted to primary care. Ten physicians independently viewed 44 taped medical visits. Five physicians were randomly assigned to manual coding and five to computer coding. The study of reproducibility explored three aspects: written diagnoses, manually coded diagnoses, and diagnoses coded using a software program. The K statistic was calculated in order to compare interobserver agreement. RESULTS: Descriptive analysis of interobserver agreement in the written diagnoses revealed an agreement rate of 70.5% (+/- 6.3). Among physicians using manual coding, the agreement rate was 70.2% (+/- 7.2). In the group using the software program, the agreement rate was 75.0% (+/- 8.7). The K coefficients were low, but three were significant with critical ratios (z) above 1.96. CONCLUSION: Results suggest that input method has no bearing on interobserver agreement and that agreement is more a function of clinical presentation of health problems than of coding process.

Abstracting and Indexing↗
PubMed1998

Use of image cytometry to classify biliary and ampullary adenocarcinomas.

OBJECTIVE: To create an objective classification system to perform TNM classification of ampullary adenocarcinoma and cholangiocarcinoma using image cytometric data derived from Feulgen-stained tumor nuclei. STUDY DESIGN: Surgically resected cases of ampullary adenocarcinoma and cholangiocarcinoma with established TNM classifications were selected on the basis of available formalin-fixed, paraffin-embedded tissue. Fifteen numerical variables related to morphometric, densitometric and textural features of each tumor nucleus were recorded. We employed a methodology based on multivariate statistical tools to characterize the association of morphonuclear variables with TNM classification. The first step consisted of identifying and selecting representative nuclei of each T class. From this "purified" data set an objective classification system was created. The classification system was assessed using internal and external validation. RESULTS: Employing ANOVA, all 15 variables were significantly associated with T classification, 11 of 15 with N and 4 with M. Multivariate analysis was employed to distinguish between T1, T2 and T3 lesions. Our methodology correctly classified 76% of T1 nuclei, 47% of T2 nuclei and 84% of T3 nuclei. Heterogeneity within an individual tumor was defined in 61% of cases included in the training set. Complete concordance between pathologic classification and the classification system was observed in 71% of an independent validation.

Adenocarcinoma↗
PubMed1998

Building manageable rough set classifiers.

An interesting aspect of techniques for data mining and knowledge discovery is their potential for generating hypotheses by discovering underlying relationships buried in the data. However, the set of possible hypotheses is often very large and the extracted models may become prohibitively complex. It is therefore typically desirable to only consider the "strongest" hypotheses, so that smaller models can be obtained that also retain good classificatory capabilities. This paper outlines how rule-based classifiers based on rough set theory and Boolean reasoning that are both small and perform well can be developed. Applied to a real-world medical dataset, the final models are shown to exhibit good performance using only a subset of the available information. Furthermore, the number of resulting rules is low and enables practical a posteriori inspection and interpretation of the models.

Classification↗