Browsing by Subject "Discriminant analysis"

Now showing 1 - 7 of 7
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    Delirium diagnosis defined by cluster analysis of symptoms versus diagnosis by DSM and ICD criteria: diagnostic accuracy study
    (BioMed Central, 2016-05-26) Sepulveda, Esteban; Franco, Jose G.; Trzepacz, Paula T.; Gaviria, Ana M.; Meagher, David J.; Palma, Jose; Viñuelas, Eva; Grau, Imma; Vilella, Elisabet; de Pablo, Joan; Department of Psychiatry, IU School of Medicine
    BACKGROUND: Information on validity and reliability of delirium criteria is necessary for clinicians, researchers, and further developments of DSM or ICD. We compare four DSM and ICD delirium diagnostic criteria versions, which were developed by consensus of experts, with a phenomenology-based natural diagnosis delineated using cluster analysis of delirium features in a sample with a high prevalence of dementia. We also measured inter-rater reliability of each system when applied by two evaluators from distinct disciplines. METHODS: Cross-sectional analysis of 200 consecutive patients admitted to a skilled nursing facility, independently assessed within 24-48 h after admission with the Delirium Rating Scale-Revised-98 (DRS-R98) and for DSM-III-R, DSM-IV, DSM-5, and ICD-10 criteria for delirium. Cluster analysis (CA) delineated natural delirium and nondelirium reference groups using DRS-R98 items and then diagnostic systems' performance were evaluated against the CA-defined groups using logistic regression and crosstabs for discriminant analysis (sensitivity, specificity, percentage of subjects correctly classified by each diagnostic system and their individual criteria, and performance for each system when excluding each individual criterion are reported). Kappa Index (K) was used to report inter-rater reliability for delirium diagnostic systems and their individual criteria. RESULTS: 117 (58.5 %) patients had preexisting dementia according to the Informant Questionnaire on Cognitive Decline in the Elderly. CA delineated 49 delirium subjects and 151 nondelirium. Against these CA groups, delirium diagnosis accuracy was highest using DSM-III-R (87.5 %) followed closely by DSM-IV (86.0 %), ICD-10 (85.5 %) and DSM-5 (84.5 %). ICD-10 had the highest specificity (96.0 %) but lowest sensitivity (53.1 %). DSM-III-R had the best sensitivity (81.6 %) and the best sensitivity-specificity balance. DSM-5 had the highest inter-rater reliability (K =0.73) while DSM-III-R criteria were the least reliable. CONCLUSIONS: Using our CA-defined, phenomenologically-based delirium designations as the reference standard, we found performance discordance among four diagnostic systems when tested in subjects where comorbid dementia was prevalent. The most complex diagnostic systems have higher accuracy and the newer DSM-5 have higher reliability. Our novel phenomenological approach to designing a delirium reference standard may be preferred to guide revisions of diagnostic systems in the future.
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    Metacarpophalangeal Pattern Profile Analysis in Clinical Genetics: An Applied Anthropometric Method
    (Wiley, 1986-06) Butler, Merlin G.; Meaney, F. John; Kaler, Stephen G.; Medical and Molecular Genetics, School of Medicine
    The hand is a complex anatomical structure with the component bones susceptible to a combination of environmental and genetic factors that may affect the bone length and width. The alterations may involve a single bone or specific group of bones. The metacarpophalangeal pattern profile (MCPP) developed by Poznanski, Garn, and others (Poznanski et al. Birth Defects VIII (5): 125–131, 1972) is a graphic representation of the relative lengthening and shortening of the 19 tubular bones of the hand useful for diagnosis, comparison of dissimilar patients, and gene carrier detection. The profile hand bone measurements are derived from posteroanterior hand radiographs and are standardized for age and sex. Specific profiles have been developed for several syndromes. Therefore, MCPP analysis has developed from a method of describing changes in the hand to a technique useful in assigning a diagnosis to a specific syndrome and evaluation of skeletal development. The current status of MCPP analysis in clinical genetics, particularly with the Prader-Labhart-Willi and Sotos syndromes, is discussed.
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    Metacarpophalangeal pattern profile analysis in diastrophic dysplasia
    (Wiley, 1987-11) Butler, Merlin G.; Gale, David D.; Meaney, F. John; Medical and Molecular Genetics, School of Medicine
    We analyzed the metacarpophalangeal pattern profile (MCPP) on 16 individuals with diastrophic dysplasia and calculated a mean syndrome profile. Correlation studies confirm clinical homogeneity of the hand profile in diastrophic dysplasia. Discriminant analysis of individuals with diastrophic dysplasia compared with a sample of normal individuals produced a function of 3 MCPP variables plus age that appears to be a useful diagnostic tool.
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    Metacarpophalangeal pattern profile analysis in fragile X syndrome
    (Wiley, 1988-12) Butler, M. G; Fletcher, M.; Gale, D. D.; Meaney, F. J.; McLeod, D. R.; Fagan, J.; Carpenter, N. J.; Opitz, J. M.; Reynolds, J. F.; Department of Medical and Molecular Genetics, School of Medicine
    We analyzed the metacarpophalangeal pattern profile (MCPP) on 18 male individuals from 16 families with fragile X—fra (X), or Martin-Bell—syndrome and calculated a mean syndrome profile. Fourteen of 18 individuals with fra (X) syndrome had significant positive correlations which indicated clinical homogeneity. Discriminant analysis of individuals with fra (X) syndrome compared with a sample of normal individuals produced a correct classification rate of 88% based on a function of 3 MCPP variables that may provide a useful tool in screening individuals for the fra (X) syndrome. Discriminant and correlation analyses of individuals with Sotos sequence and individuals with fra (X) syndrome did not identify MCPP similarities. Therefore, there was no MCPP evidence in our study of patients with Sotos sequence and fra (X) chromosome expression.
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    Metacarpophalangeal pattern profile analysis in Prader-Willi syndrome. A follow-up report on 38 cases
    (Wiley, 1985-07) Butler, Merlin G.; Meaney, F. John; Medical and Molecular Genetics, School of Medicine
    Metacarpophalangeal pattern profile (MCPP) was determined on 38 Prader-Willi syndrome individuals and compared with a previous report on 16 patients. Chromosome analysis showed an interstitial deletion of the long arm of chromosome 15 in 20 subjects and normal chromosome results in the remaining 18 individuals. The mean hand profile of 38 individuals was essentially flat while the profiles for the two groups based on chromosome findings were separate in the metacarpal area. Correlation studies confirmed the homogeneity of the deletion group relative to Prader-Willi syndrome individuals with normal chromosomes. Discriminant analysis of Prader-Willi syndrome versus control individuals produced a function of three MCPP variables plus age which may be applied as another diagnostic tool.
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    Metacarpophalangeal pattern profile analysis in Robinow syndrome
    (Wiley, 1987-05) Butler, Merlin G.; Gale, David D.; Meaney, F. John; Wadlington, William B.; Robinow, Meinhard; Medical and Molecular Genetics, School of Medicine
    We analyzed the metacarpophalangeal pattern profile (MCPP) on 15 individuals with Robinow syndrome and calculated a mean Robinow syndrome profile. Correlation studies confirm clinical homogeneity of the hand profile in the Robinow syndrome. Discriminant analysis of individuals with Robinow syndrome compared with a sample of normal individuals produces a function of 6 MCPP variable that may provide a useful tool for diagnosis.
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    Spectroscopic and chemometric analysis of automotive clear coat paints by micro fourier transform infrared spectroscopy
    (2014) Osborne Jr., James D.; Goodpaster, John V. (John Vincent); Manicke, Nicholas; Minto, Robert; Picard, Christine
    Clear coats have been part of automotive field paint finishes for several decades. Originally a layer of paint with no pigment, they have evolved into a protective layer important to the appearance and longevity of the vehicle's finish. These clear coats have been studied previously using infrared spectroscopy and other spectroscopic techniques. Previous studies focused on either all the layers of an automobile finish or on chemometric analysis of clear coats using other analytical techniques. For this study, chemometric analysis was performed on preprocessed spectra averaged from five separate samples. Samples were analyzed on a Thermo-Nicolet Nexus 670 connected to a Continuμm™ FT-IR microscope. Two unsupervised chemometric techniques, Agglomerative Hierarchical Clustering (AHC) and Principal Component Analysis (PCA), were used to evaluate the data set. Discriminant analysis, a supervised technique, was evaluated using several known qualifiers; these included cluster group from AHC, make, model, and year. Although discriminant analysis confirmed the AHC and PCA results, no correlation to make, model, or year was indicated.