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Differential Scoring Patterns on the Clock Drawing Test: a Comparison of Vascular Dementia and Alzheimer's Dementia.

Description: This study examined differences in scoring patterns among those diagnosed with Alzheimer's dementia and vascular dementia on the clock-drawing test. Archival clock drawing data was retrieved on 279 patients presenting at a county hospital-based memory clinic. Analysis of drawings was based on frequency of qualitative errors, as well as an overall quantitative score. Mean comparisons found those patients with Alzheimer's dementia to perform worse on both quantitative and qualitative scoring measures. However, Pearson's chi-squared test revealed a significantly higher rate of spacing errors among subjects with vascular dementia. Such lends support to my hypothesis that impaired executive functioning in vascular dementia patients would lead to poor qualitative performance. Logistic regression found significant predictive ability for the qualitative criteria in diagnosis (χ2 = 25.49, p < .001), particularly the rate of omission (z = 8.96, p = .003) and addition errors (z = 7.58, p = .006). Such findings hold important implications for the use of qualitative criteria in cognitive screening assessments.
Date: May 2006
Creator: Everitt, Alaina
Partner: UNT Libraries

Effects of Cautioning and Education in the Detection of Malingered Mild Traumatic Brain Injury

Description: This study examined the effectiveness of cautioning and education on simulating a mild traumatic brain injury on several neuropsychological measures. The measures used included the Word Memory Test (WMT), Wechsler Adult Intelligence Scales® - Third Edition (WAIS®-III), Wechsler Memory Scales®-3rd Edition instrument (WMS®-III), 16-item version of the Rey Memory Test, and a self-report symptom checklist. Five experimental groups were used including clinical and non-clinical controls, as well as three simulation groups. The design and implementation of this study also attempted to correct several methodological short comings of prior research by increasing the incentives for participants, expanding the generalizability of findings and examining research compliance and participant self-perception through debriefing. Discriminant analysis was utilized to determine if specific functions existed that would correctly classify and distinguish each experimental group. Several discriminant functions had at least moderate canonical correlations and good classification accuracy. Results also include utility estimates given projected varying base rates of malingering.
Date: May 2006
Creator: Scholtz, Brendon P.
Partner: UNT Libraries

TRWG developmental pathway for biospecimen-based assessment modalities

Description: The Translational Research Working Group (TRWG) was created as a national initiative to evaluate the current status of NCI's investment in translational research and envision its future. The TRWG conceptualized translational research as a set of six developmental processes or pathways focused on various clinical goals. One of those pathways describes the development of biospecimen-based assays that utilize biomarkers for the detection, diagnosis, prognosis, and assessment of response to cancer treatment. The biospecimen-based assessment modality (BM) pathway was conceived not as comprehensive description of the corresponding real-world processes, but rather as a tool designed to facilitate movement of a candidate assay through the translational process to the point where it can be handed off for definitive clinical testing. This paper introduces the pathway in the context of prior work and discusses key challenges associated with the biomarker development process in light of the pathway.
Date: September 3, 2008
Creator: Group, Translational Research Working; Srivastava, Sudhir; Gray, Joe W.; Reid, Brian J.; Grad, Oren; Greenwood, Addison et al.
Partner: UNT Libraries Government Documents Department

Neurocognitive implications of diabetes on dementia as measured by an extensive neuropsychological battery.

Description: Diabetes is a disease with a deleterious pathology that currently impacts 4.5 million individuals within the United States. This study examined the ability of a specific neuropsychological battery to identify and classify dementia type, investigated the impact of diabetes on cognition and analyzed the ability of the memory measures of the 7 Minute Screen (7MS) and the Rey-Osterrieth Recall to correctly categorize dementia type when not used in combination with a full battery. The battery in addition to exhaustive patient history, medical chart review and pertinent tests were used in initial diagnosis. Results indicated the battery was sufficient in the identification and classification of dementia type. Within the sample, diabetes did not appear to significantly impact overall battery results whereby only two measures were minimally affected by diabetes. Finally, the memory measures of the 7MS and the Rey-Osterrieth Recall were sufficient to predict membership into the Alzheimer's (AD) and vascular dementia (VD) groups with 86.4% accuracy. The classification percentage dropped to 68.3% with addition of the mild cognitive impairment category. The full battery correctly classified AD and VD dementia 87.5% and appeared to be the most robust.
Date: December 2008
Creator: Harris, Rebekah Lynn
Partner: UNT Libraries

The Effectiveness of the Geriatric Depression Scale to Distinguish Apathy From Depression in Alzheimer's Disease and Related Dementias.

Description: Early detection of Alzheimer's disease (AD) and related dementias in the elderly is critical for improving treatment methods and is a necessary component for improving public health interventions. One of the earliest and most common behavioral syndromes of AD is apathy and is associated with executive dysfunction. Apathy in AD is often misdiagnosed as depression due to an overlap in symptoms. Studies that have found depression to be associated with executive dysfunction have not always controlled for the presence of apathy. The Geriatric Depression Scale (GDS) is a widely used instrument designed to assess depression in the elderly. This study utilized the GDS and a set of standard neuropsychological instruments to investigate the relationship between apathy, depression, and executive functions in individuals with AD and related dementias. The first objective of this study was to determine if apathy has a greater impact on executive functions compared to depression in AD and related dementias. The second objective was to determine the effectiveness of the GDS as a screen for apathy. The results of the analyses did not support the hypotheses. However, exploratory analyses suggested a possible non-linear relationship with apathy and various levels of dementia severity. Exploratory analysis also suggested mean levels of endorsement for apathy varied by diagnosis. Further research is warranted to investigate this relationship and the GDS endorsement patterns for caregivers regarding their impression of the demented individual.
Date: August 2008
Creator: Davis, Tommy E., Jr.
Partner: UNT Libraries

Interactive Volume Rendering of Diffusion Tensor Data

Description: As 3D volumetric images of the human body become an increasingly crucial source of information for the diagnosis and treatment of a broad variety of medical conditions, advanced techniques that allow clinicians to efficiently and clearly visualize volumetric images become increasingly important. Interaction has proven to be a key concept in analysis of medical images because static images of 3D data are prone to artifacts and misunderstanding of depth. Furthermore, fading out clinically irrelevant aspects of the image while preserving contextual anatomical landmarks helps medical doctors to focus on important parts of the images without becoming disoriented. Our goal was to develop a tool that unifies interactive manipulation and context preserving visualization of medical images with a special focus on diffusion tensor imaging (DTI) data. At each image voxel, DTI provides a 3 x 3 tensor whose entries represent the 3D statistical properties of water diffusion locally. Water motion that is preferential to specific spatial directions suggests structural organization of the underlying biological tissue; in particular, in the human brain, the naturally occuring diffusion of water in the axon portion of neurons is predominantly anisotropic along the longitudinal direction of the elongated, fiber-like axons [MMM+02]. This property has made DTI an emerging source of information about the structural integrity of axons and axonal connectivity between brain regions, both of which are thought to be disrupted in a broad range of medical disorders including multiple sclerosis, cerebrovascular disease, and autism [Mos02, FCI+01, JLH+99, BGKM+04, BJB+03].
Date: March 30, 2007
Creator: Hlawitschka, Mario; Weber, Gunther; Anwander, Alfred; Carmichael, Owen; Hamann, Bernd & Scheuermann, Gerik
Partner: UNT Libraries Government Documents Department

A Descriptive Study of Selected Characteristics of Aged First Admissions to a Private Psychiatric Hospital 1959-1963

Description: The purpose of this thesis is to provide a descriptive study of psychiatric and social variables related to aged first admissions to a private psychiatric hospital in the calendar years 1959 through 1963. The study also seeks to determine what, if any, relationship exists between background characteristics of the patients and their diagnoses. Finally, the diagnosis of the patient is compared with a series of patient outcome variables to determine the relationship, if any, between diagnosis and selected recovery variables. Due to the nature of the data used, the emphasis of the thesis is upon describing relationships rather than testing hypotheses.
Date: January 1968
Creator: Smith, Joseph Clair
Partner: UNT Libraries

Brain Dysfunction Indication on the Bender-Gestalt Test: a Validation of the Embree/Butler Scoring System

Description: The Embree/Butler scoring system served as criterion for ascertaining brain dysfunction on the protocols of 100 subjects--50 had been diagnosed by health professionals as having brain dysfunction, and 50 had been diagnosed as having no brain dysfunction. In comparing the hospital's diagnoses with those of the Embree/Butler method, the data strongly supported the hypothesis that the Embree/Butler scoring system did effectively discriminate (chi square of 77.99 < .01) between those with organic brain syndrome (or cerebral dysfunction) and those with psychiatric classification. A point-biserial correlation was used to distinguish the relationship between diagnosis and the score. A cutoff score of above 14 produced the least false-negative or false-positive evaluations.
Date: December 1981
Creator: Henderson, J. Louise
Partner: UNT Libraries

Detection of Malingering on Raven's Standard Progressive Matrices and the Booklet Category Test

Description: The capacity of Raven's Standard Progressive Matrices (SPM) and the Booklet Category Test (BCT) to discriminate between groups of brain-injured, simulated malingering, and normal participants was investigated in this study. Exploratory analyses were also conducted to examine the differences between groups categorized as sophisticated and naive fakers. Clinical decision rules and discriminant function analyses were utilized to identify malingerers. Clinical decision rules ranged in hit rates from 41% to 78%, in sensitivity from 2% to 100%, and in specificity from 86% to 100%. Discriminant functions ranged in hit rates from 81% to 86%, in sensitivity from 68% to 73% and in specificity from 82% to 87%. Overall, the least helpful detection method examined was below chance responding on either measure, while the most efficient was gross errors for SPM.
Date: December 1997
Creator: Isler, William C. (William Charles)
Partner: UNT Libraries

The Substance Abuse Subtle Screening Inventory: a Predictive Validity Study with Criminal Offenders Mandated to Rehabilitative Treatment

Description: The Substance Abuse Subtle Screening Inventory was constructed to screen for substance abuse patterns despite non-admittance of respondents. Predictive validity studies of the SASSI are limited, and are not available for probationers. Participants were 147 male and 54 female probationers mandated to treatment. Overall differences among SASSI scales were significant for treatment compliance and outcome. Higher SASSI scales were found among those probationers who were compliant/successful. Individual scales were not significantly different, however, a trend was revealed; those respondents who scored higher tended to comply/succeed in treatment. The SASSI alone accurately classified 59.7% of respondents. In summary, the SASSI's use in predicting treatment outcome is limited and should be employed with concomitant data.
Date: August 1996
Creator: Flores, Johnny Martin
Partner: UNT Libraries

Performance of Psychiatric and Head Injury Patients on the General Neuropsychological Deficit Scales

Description: Reitan and Wolfson's General Neuropsychological Deficit Scale and Left and Right Neuropsychological Deficit Scales were applied to Halstead-Reitan test data of individuals with psychotic or substance abuse disorders with and without a head injury.
Date: August 1997
Creator: Collingwood, Lisa M. (Lisa Marie)
Partner: UNT Libraries

The utility of the McCarron-Dial System in determining location of brain lesion.

Description: Among the goals of neuropsychological assessment are to detect the presence of brain damage, localize which areas of the brain may be dysfunctional, and describe subsequent functional impairments. The sensitivity of neuropsychological instruments in carrying out these functions has long been a question of debate. The purpose of the present study was to determine the utility of various performance level indictors and lateralizing indicators from the McCarron-Dial System Neuropsychological Assessment Battery (MDS) in ascertaining the presence or absence of brain damage as well as location of lesion. Models used in the present study appear to provide increased classification accuracy compared to other studies utilizing the MDS. The MDS was also shown to be comparable to other well-known neuropsychological batteries, including the Halstead-Reitan Neuropsychological Test Battery (HRB) and the Luria-Nebraska Neuropsychological Battery (LNNB) with regard to distinguishing between those with brain damage and normal controls, and also localizing brain lesion. The results of this study offer clinicians parsimonious models to evaluate for presence of lesion and its location so this information may be used to make accurate, thorough diagnoses and appropriate treatment and rehabilitation recommendations.
Date: August 2004
Creator: Taylor, Erin Kathleen
Partner: UNT Libraries

Development of an Expert System to Teach Diagnostic Skills

Description: The primary purpose of the study was to develop an expert system that could C D perform medical diagnoses In selected problem areas, and C2) provide diagnostic Insights to assist medical students In their training. An expert system Is a computer-based set of procedures and algorithms that can solve problems In a given domain. Two research questions were proposed. The first was "Given a problem space defined by a matrix of diseases and symptoms, can a computer-based model be derived that will consistently perform accurate and efficient diagnoses of cases within that problem area?" The second question was "If the techniques derived from the model are taught to a medical student, is there a subsequent improvement of diagnostic skill?" An expert system was developed which met the objectives of the study. It was able to diagnose cases in the two problem areas studied with an accuracy of 94-95%. Furthermore, it was able to perform those diagnoses in a very efficient manner, often using no more than the theoretical minimum number of steps. The expert system employed three phases: rapid search by discrimination, confirmation by pattern matching against prototypes, and elimination of some candidates (impossible states) by making use of negative information. The discrimination phase alone achieved accuracies of 73-78%. By comparison, medical students achieved mean accuracies of 54-55% in the same problem areas. This suggests that novices could improve their diagnostic accuracy by approximately 20% by following the simple rules used in the first phase of the expert system. Curricular implications are discussed. When 49 first-year medical students at the Texas College of Osteopathic Medicine were exposed to some of the insights of the expert system by means of a videotaped 10- minute lecture, their diagnostic approach was modified and the accuracy of their diagnoses did improve. However, the degree ...
Date: August 1990
Creator: Elieson, S. Willard (Sanfred Willard)
Partner: UNT Libraries

A Study of the Relationship Between the Responses Given by Paretics and Mixed Schizophrenics on the Bender-Gestalt Visual Motor Test

Description: The purpose of this study is to present quantitative findings of the Bender-Gestalt Visual Motor Test which will indicate the effectiveness of this media as an instrument of differential diagnosis when applied to General Paresis and Mixed Schizophrenia.
Date: 1951
Creator: Blackwell, Dale W.
Partner: UNT Libraries

The CDC's Case Definition of AIDS: Implications of Proposed Revisions

Description: This background paper examines the epidemiologic evidence used by the CDC in deciding to revise the AIDS case definition and the impact the proposed definition will have on surveillance. The paper also explores the logistical consequences and other implications of the revised definition, including its impact on Social Security disability determinations.
Date: June 1990
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

Haptic Visual Sensory Integration: A Comparison Between Normal, Schizophrenic, and Brain Damaged Groups

Description: Neuropsychological tests have been used in differentially diagnosing schizophrenic and brain damaged populations. Research indicated some subgroups of schizophrenia exhibit certain symptoms of brain damage; and that schizophrenia involves difficulty in sensory integration. The Haptic Visual Discrimination Test (HVDT) designed to test tactilevisual integration, Bender Gestalt, and Information and Digit Symbol subtests of the WAIS were used to test performance abilities of forty schizophrenic subjects, forty subjects medically diagnosed as brain damaged (10 right hemisphere, 10 left hemisphere, and 20 diffuse), and normals as defined by the standardized age norm scores.
Date: August 1982
Creator: Wigodsky, Ann
Partner: UNT Libraries

Distortion-free magnetic resonance imaging in the zero-field limit

Description: MRI is a powerful technique for clinical diagnosis and materials characterization. Images are acquired in a homogeneous static magnetic field much higher than the fields generated across the field of view by the spatially encoding field gradients. Without such a high field, the concomitant components of the field gradient dictated by Maxwell's equations lead to severe distortions that make imaging impossible with conventional MRI encoding. In this paper, we present a distortion-free image of a phantom acquired with a fundamentally different methodology in which the applied static field approaches zero. Our technique involves encoding with pulses of uniform and gradient field, and acquiring the magnetic field signals with a SQUID. The method can be extended to weak ambient fields, potentially enabling imaging in the Earth's field without cancellation coils or shielding. Other potential applications include quantum information processing and fundamental studies of long-range ferromagnetic interactions.
Date: July 9, 2009
Creator: Kelso, Nathan; Lee, Seung-Kyun; Bouchard, Louis-S.; Demas, Vasiliki; Muck, Michael; Pines, Alexander et al.
Partner: UNT Libraries Government Documents Department

Preimplantation genetic diagnosis for gender selection in the United States

Description: Preimplantation genetic diagnosis (PGD) of gender selection for non medical reasons has been considered an unethical procedure by several authors and agencies in the Western society on the basis of disrupting the sex ratio, being discriminatory againsts women and disposal of normal embryos of the non desired gender. In this study, the analysis of a large series of PGD procedures for gender selection from a wide geographical area in the United States, shows that in general there is no deviation in preference towards any specific gender except for a preference of males in some ethnic populations of Chinese, Indian and Middle Eastern origin that represent a small percentage of the US population. In cases where only normal embryos of the non-desired gender are available, 45.5% of the couples elect to cancel the transfer, while 54.5% of them are open to have transferred embryos of the non-desired gender, this fact being strongly linked to cultural and ethnical background of the parents. In addition this study adds some evidence to the proposition that in couples with previous children of a given gender there is no biological predisposition towards producing embryos of that same gender. Based on these facts, it seems that objections to gender selection formulated by ethics committees and scientific societies are not well-founded.
Date: August 20, 2009
Creator: Colls, P.; Silver, L.; Olivera, G.; Weier, J.; Escudero, T.; Goodall, N. et al.
Partner: UNT Libraries Government Documents Department

Costs and Effectiveness of Cholesterol Screening in the Elderly

Description: This paper reviews the evidence that elevation of serum cholesterol (hypercholesterolemia) is an independent risk factor for cardiovascular disease in the elderly and that the detection and treatment of hypercholesterolemia in an elderly individual who does not have clinically apparent heart disease will diminish overall morbidity or mortality. It also estimates health care expenditures associated with screening and treatment of hypercholesterolemia in the elderly.
Date: April 1989
Creator: United States. Congress. Office of Technology Assessment.
Partner: UNT Libraries Government Documents Department

Grid Logging: Best Practices Guide

Description: The purpose of this document is to help developers of Grid middleware and application software generate log files that will be useful to Grid administrators, users, developers and Grid middleware itself. Currently, most of the currently generated log files are only useful to the author of the program. Good logging practices are instrumental to performance analysis, problem diagnosis, and security auditing tasks such as incident tracing and damage assessment. This document does not discuss the issue of a logging API. It is assumed that a standard log API such as syslog (C), log4j (Java), or logger (Python) is being used. Other custom logging API or even printf could be used. The key point is that the logs must contain the required information in the required format. At a high level of abstraction, the best practices for Grid logging are: (1) Consistently structured, typed, log events; (2) A standard high-resolution timestamp; (3) Use of logging levels and categories to separate logs by detail and purpose; (4) Consistent use of global and local identifiers; and (5) Use of some regular, newline-delimited ASCII text format. The rest of this document describes each of these recommendations in detail.
Date: April 1, 2008
Creator: Tierney, Brian L; Tierney, Brian L & Gunter, Dan
Partner: UNT Libraries Government Documents Department