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Decision making in end stage kidney disease (ESKD) in Ghana : exploring patient and clinician perspectivesAppiah Boateng, Edward January 2016 (has links)
Introduction This study was carried out in Ghana, where the incidence of end stage kidney disease (ESKD) is increasing in a context of limited treatment options. Understanding the issues patients with ESKD grapple with when diagnosed with this life-threatening condition is essential to improve healthcare policy and practice in such low- and middle-income settings. In the absence of evidence related to the African ESKD patient journey, this study aimed at exploring how decisions about ESKD management are being made, especially in under-resourced settings where specific treatment modalities are not always available. The study addresses an important gap in the literature concerning choice and decision making in an international context. The key research question for this study is, in terms of the context, does the problem of limited resources in low- and middle-income countries present different choices to the patient with ESKD facing decisions about their treatment? Methodology and Methods The study employed a qualitative research design, using grounded theory methodology. Twenty-seven participants in three renal centres, comprising twenty-two patients with ESKD and five clinicians, were selected using the theoretical sampling approach and interviewed for this study. Constant comparative analysis was employed in data analysis. Results A conceptual map depicting the ESKD patient journey and key phases of decision making was developed from this study. Ghanaian patients with ESKD are mostly unaware of the implications of their initial symptoms, and end up delaying seeking healthcare from a hospital. Some of those who seek care from hospitals are initially diagnosed with and treated for other conditions other than ESKD. Thus, many patients with ESKD in Ghana present late to a renal centre. Treatment for ESKD is initiated for various reasons, including, initially, the urgent need to avoid premature death. Many approach their condition in terms of hoping for a cure and do not always understand the chronic nature of their condition. Decisions on initiating haemodialysis (HD) are mostly shared between clinicians and patients and/or their families but the process is mainly driven by the need to ascertain patient and family’s ability to finance HD, rather than considering other aspects of treatment burden. The subject of death or conservative management is not openly discussed and, once this is brought up, patients usually do everything possible to opt for another form of treatment, including the simultaneous use of other non-RRT and traditional or faith-based healing approaches. Clinicians play vital roles in the decision making of patients with ESKD although they have general feelings of helplessness while supporting these patients. Convergence between individuals’ experiences of realities of living with and managing ESKD, and support from clinicians in the renal setting ultimately leads to a reconstruction of health expectations that commensurate management goals of ESKD. This sums up the substantive theory of ‘reconstructing health expectations’ that was generated from this study. Conclusions Financial and geographical inaccessibility of renal replacement therapy (RRT) as well as the relative lack of biomedical treatment choices make decision making daunting for the individual with ESKD in Ghana. Reluctance to discuss death as a potential outcome is a hindrance to the consideration of conservative management as a treatment option. Effective realignment of healthcare policies to address changing patterns of diseases is necessary to contribute to prevention, early detection and effective management of ESKD in the country. An improved approach to conservative management is urgently required, including training support for clinicians on shared decision making as well as sensitisation of patients on this modality.
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Characterisation and clinical studies of an antimicrobial urinary catheter for long-term useBelfield, Katherine January 2018 (has links)
Background and Aims: Catheter-associated urinary tract infections (CAUTI) are a common and costly complication of indwelling urinary catheterisation. No commercial technology exists that protects against the major uropathogens for the lifetime of a long-term catheter. Silicone indwelling urinary catheters were impregnated with the antimicrobials (AUC) rifampicin, sparfloxacin, and triclosan to confer antimicrobial activity. With the overall aim of delivering this technology to urinary catheters users, this thesis aims to firstly, understand the profile of micoorganisms attached to indwelling urinary catheters. Secondly, using a combination of studies investigating the impregnated catheter surface and in vitro models, determine the ability of the AUC to resist mineral encrustation. Thirdly, this thesis will assess the protective activity of the AUC against multi-drug resistant organisms and Enterococcus spp. Finally, the safety and patient acceptability of this AUC will be assessed by a single-centre clinical trial. Methods: Urinary catheters were collected from patients at Nottingham University Hospitals NHS Trust (NUHT), and also over one year from one volunteer. General microbiological methods, including a new method of processing urinary catheters and MALDI-ToF were employed to identify and quantify attached microorganisms. Pulsed-field gel electrophoresis (PFGE) and similarity analysis determined the relationship between isolates of the same species isolated from catheters collected consecutively from the volunteer. The catheter surfaces were investigated after antimicrobial impregnation and soaking using atomic force microscopy and bacterial attachment assays. Reduction of mineral encrustation on the AUC was investigated in the presence and absence of bacteria. Spectrophotocolourimetry quantified phosphate deposition in a static and in vitro flow model. The protective duration of the AUC against Enterococcus spp. and multi-drug resistant bacteria was investigated in a clinically predictive in vitro model. A single-centre, non-randomised safety and patient acceptability study was conducted. The primary outcome measure was rate of adverse events attributable to antimicrobial impregnation. Secondary outcome measures included patient acceptability, withdrawal before the end of the trial, and microorganism colonisation of trial catheters. Results:Sixty-one urinary catheters were collected from patients at NUHT. E. coli and Enterococcus faecalis were the most commonly isolated organisms. A novel method was developed to isolate micoorganisms from the catheter lumens and balloons separately. Nine consecutive urinary catheters were collected from one volunteer over one year. Methicillin-susceptible Staphylococcus aureus, E. faecalis, Citrobacter koseri, and Pseudomonas aeruginosa were isolated from many of the nine catheters over the course of the year. PFGE revealed the isolates were indistinguishable, except for three P. aeruginosa isolates, which were closely related but differed by a 2-3 band difference by PFGE. Surface characteristics of silicone urinary catheters were not adversely affected by antimicrobial impregnation. The AUC prevented blockage and reduced phosphate deposition when challenged with Proteus mirabilis in static and flow models. The AUC was not able to consistently eradicate E. faecalis and E. faecium isolates. The AUC resisted colonisation by methicillin-resistant S. aureus, methicillin-resistant Staphylococcus epidermidis, MSSA, Staphylococcus saprophyticus, extended-spectrum beta-lactamase producing E. coli, New Delhi metallo-beta-lactamase producing E. coli for approximately 12 weeks. Thirty patients were recruited to the safety clinical trial, which demonstrated the AUC was safe and was acceptable to the majority of participants. Only one adverse event was reported that was ‘probably’ associated with antimicrobial impregnation of the catheters and it was mild and resolved within 48 hours. There were significantly less bacterial isolates attached to the balloons of trial catheters compared to the matched original catheters. Conclusions: The AUC is safe and effective technology for long-term catheter users. Next steps include a clinical trial of efficacy and commercialisation.
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Factors influencing the removal of immune complex deposits from the renal glomerulusFurness, Peter Norman January 1988 (has links)
This thesis describes a study of the mechanisms involved in the elimination of established, morphologically identifiable electron dense deposits from the glomeruli of rats with chronic serum sickness. The initial experiments established the experimental model and evaluated the effects of variations in the method of administration, the antigen dose and charge, and the route of administration. The model was further characterized in terms of the progression of the morphological, functional and biochemical abnormalities induced. Methods were developed to measure the amount of radio-labeled antigen in isolated glomeruli, and to measure the volume fraction of the electron dense deposits in glomeruli. Study was then limited to the first two weeks of recovery from chronic serum sickness, after injections of antigen have ceased, to ascertain the rates at which the antigen and deposits were removed. The influence of a variety of forms of intervention during this recovery period was then assessed. Manoeuvres which increased the level of circulating anti-BSA antibody were found to inhibit the removal of antigen and deposits from glomeruli. This effect was confirmed by passive immunization with immune rat serum. Manoeuvres which increased the number or activity of glomerular macrophages had no detectable effect on the removal of antigen or deposits. In the absence of plasma complement, the removal of antigen virtually ceased after four days. Cobra venom factor treated rats had lower proteinuria than controls, despite having a heavier antigen load. Manoeuvres which altered the, glomerular filtration rate and renal haemodynamics did not alter the rate of removal of antigen or deposits; nor did the administration of highly cationic molecules. The administration of large doses of heparin enhanced the rate of removal of antigen from the glomerulus, though an effect on deposit volume was not detected.
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Prostate cancer risk factors : a UK population based case-control study centered on chronic diseases, medications, sunlight and dietRobinson, Fredie January 2012 (has links)
Background: Prostate cancer risk has been associated with several environmental factors but there is little information to indicate the effects of timing and of lifetime exposures that may add to the risk. This thesis aims to investigate the association of six main areas that may contribute to prostate cancer risk (1) body shape & fat distribution, (2) chronic diseases/conditions (diabetes mellitus, hypertension, ischaemic heart diseases and hypercholesterolemia), (3) statin medications (4) painkillers (NSAIDs and paracetamol), (5) skin & sunlight exposure and (6)diet (isoflavones, selenium, vitamin D & lycopene). The exposures will be investigated at different stages of life for subsequent effects on cumulative prostate cancer risk. Methodology: This study is a part of "The UK Prostate Cancer Study: Gene-Environment Interactions", which is an ongoing large scale case-control study and a collaboration between the University of Nottingham, University of Warwick and the Institute of Cancer Research UK. Data were collected using questionnaires. Subjects were recruited between the years of 1999 to 2009 as cases and controls from hospitals and GPs' referrals in England. Possible risk factors for prostate cancer are investigated through statistical analyses using unconditional logistic regression to obtain odds ratios (OR) and confidence intervals. Results: The response rate was 85.0% among cases and 74.4% among controls, with a total of 4041 males (1963 cases and 2078 controls) recruited into the study. The mean age among cases and controls was 59.6 and 59.1 years respectively. Multivariate analysis of socio-demographic factors showed education, ethnic group and family history were statistical significantly associated with prostate cancer risk and therefore are treated as confounders. Further, (1) Body fat distribution of 'apple' and 'oval' shapes were found to have protective effect towards prostate cancer when compared with a symmetrical shape with an OR of 0.69 (95% CI: 0.55- 0.87) and 0.73 (95% CI 0.53-1.00) respectively, however body shape at age 20's, 30's, 40's and last 5 years showed no statistical difference between cases and controls. (2) The cumulative duration of diabetes mellitus categorised as 5 years or more and 10 years or more when compared to non-diabetic individuals had a protective effect towards prostate cancer risk at OR 0.45 (95%CI: 0.27-0.75) and 0.44 (95% CI: 0.22-0.86) respectively while hypertension, hypercholesterolemia and ischaemic heart disease did not associate with prostate cancer risk. (3) Use of Statins for less than 5 years compared to non-users, produced an OR 0.61 (95%CI: 0.47-0.82). A dose response relationship for duration of use was also seen. (4) Paracetamol showed a protective effect for prostate cancer risk when used for 20 years to 30 years when compared to none-users, OR 0.54 (95%C1: 0.28-1.00). Similarly paracetamol showed a cumulative risk reduction against prostate cancer for all categories of use of up to 20 years or more. However aspirin and ibuprofen did not show any statistical significant associations with prostate cancer risk. (5) Higher exposure to sunlight received in non-working situations and more frequent use of suntan cream showed protective effects against prostate cancer and also when accounted for exposure at different stages of life age. (6)Dietary isoflavones and tablet supplements of selenium at higher intake quartiles levels showed a protection effect against prostate cancer risk when compared to lowest quartile intake. New surrogate indicators for body size and sunlight exposure and a proposed model for overall vitamin D levels from sunlight and dietary sources were also introduced. Conclusions: Body fat distribution of 'apple' and 'oval' body forms, diabetes mellitus, statin usage, higher exposure to sunlight and higher dietary intakes of isoflavones were shown to associate with a decreased risk for prostate cancer. The findings of this case-control study strengthen and support the current understanding of environmental factors associated with prostate cancer risk, whilst at the same time provides further evidence on the effects of exposure at different stages in life and their cumulative effect, as well identifying new surrogate indicators as parameters measurement for such exposures.
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Urinary incontinence in hospital in-patients : a nursing perspectiveCheater, Francine M. January 1990 (has links)
Urinary incontinence is a common health problem with not only physical, but also far-reaching psychological and social implications for the sufferer, her family and carers. Assisting patients with meeting their eliminatory needs is a fundamental part of nursing care. Incontinence is encountered in almost every sphere of clinical practice and is a problem with which nurses are often directly concerned. Nurses, in association with other members of the health care team, have considerable potential to help patients regain continence, or when this is not possible, to ensure that the individuals concerned, and their relatives or carers, can cope effectively with the problem, both physically and psychologically. This is an area of nursing care, however, which to date has attracted little research. The studies undertaken in this thesis sought to examine the nursing assessment and management of the care of patients with urinary incontinence in acute medical and care of the elderly wards. The research comprises of a sequence of studies which examined the problem from a number of perspectives. Methods of data collection included nurse and patient self-, reports, the examination of nursing and medical documentation, direct observation and self-completed questionnaires. Findings indicated that urinary incontinence was common in acute medical and care of the elderly wards, and that a considerable proportion of patients had indwelling catheters to manage the problem. Nurses were not always aware of patients' incontinence problems and their assessments concerning important aspects of the symptom were frequently unreliable. Further inadequacies in nurses' assessments, as well as in the management of the care of patients with incontinence, were identified from an examination of the nursing and medical records, and observations of verbal hand-over reports. Qualified nurses and learners appeared ill-informed about the causes of incontinence, and the majority had little knowledge of the range of factors which need to be considered to ensure that a systematic assessment of the problem is carried out. Despite considerable scope for the provision of rehabilitative care for incontinence sufferers, many nurses appeared to have a limited appreciation of their potential for initiating such care. Evidence collected from the nursing and medical records, the verbal hand-over reports and nurses' questionnaires, suggested that the management of patients with incontinence still focuses predominantly on measures which aim to contain the problem with little attention being given to rehabilitative interventions. A considerable proportion of the charge nurses, and the majority of the other qualified nursing staff, stated they had not received any continuing in-service education relevant to the promotion of continence or management of incontinence since their basic training. Nurses exhibited positive attitudes, overall, towards the management of incontinence but their responses indicated that a number of common misconceptions surrounding the problem persist. The enrolled nurses demonstrated significantly less positive attitudes towards the management of patients with incontinence than other grades of nurses. Similarly, the nursing staff who worked in the slow-stream rehabilitation care of the elderly wards showed significantly less positive attitudes towards incontinence than the nurses working in other types of wards. The implications of the findings of these studies for nursing practice, education and further research are discussed.
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Micronutrient losses during renal replacement therapy for acute kidney injuryOh, Weng Chin January 2017 (has links)
Malnutrition is common in acute kidney injury (AKI) patients, particularly on the ICU, where they often receive renal replacement therapy (RRT). RRT may exacerbate loss of water-soluble micronutrients (e.g. trace elements, amino acids and B-vitamins). No clinical study has quantified these losses and contrasted between types of RRT that use different methods to remove solutes i.e. by diffusion (intermittent haemodialysis, IHD) by convection (continuous veno-venous haemofiltration, CVVH) or by a combination of both (sustained low-efficiency diafiltration, SLEDf). Using a prospective, observational design patients (n=24 per modality) were consented before their first treatment session. Blood and RRT effluent (dialysate or filtrate) were sampled at baseline (pre-RRT), mid and end-RRT. Amino acids were measured by HPLC, trace elements by ICP-MS and B-vitamins (B1, B3, B6, B9, B12) by LC-MS. Plasma concentrations were corrected for dialysis dose using the urea reduction ratio (for IHD & SLEDf, but not CVVH). Micronutrient losses (mass-corrected) were calculated as concentration × RRT effluent volume, corrected for plasma concentration and RRT dose (i.e. solute removal index). Data were analysed by restricted maximum likelihood estimating equations (Genstat v16, VSNi Ltd, UK). Patients receiving CVVH had significantly higher plasma amino acids, but not plasma trace elements, at baseline (amino acids: CVVH, 3762 ± 357; IHD, 2039 ± 337; SLEDf, 2505 ± 423 µmol/L; trace elements: IHD, 4156 ± 465; SLEDf 3732 ± 521; CVVH 3982 ± 465 µg/L). At RRT end, plasma amino acids and trace elements had significantly reduced (429 ± 223 µmol/L; 600 ± 400 µg/L, respectively). No trace element was lost to a greater extent between types of RRT, but many ( > 10) individual amino acids declined to a much greater extent with SLEDf vs. HD or CVVH (e.g. effect size for lysine was -64 ± 23 µmol/L). Two significant sources of micronutrient loss were noted: to effluent and through dialyser adsorption. The latter contributed < 1g amino acids but in effluent recorded losses of up to 25g were noted with CVVH (5-10g for IHD and SLEDf, respectively). Effluent losses of trace elements varied significantly, but in all cases were greater for CVVH (e.g. effect size for copper was +850 ± 475 µg vs. HD or SLED-F). B-vitamins were not detectable in effluent. Significant loss of micronutrients during RRT, particularly for patients in ICU, is a possible aggravating factor for patients known to be at high risk of malnutrition. The type of RRT used influences the pattern of loss but not consistently for all nutrients. Adsorption of amino acids to dialysers adds a small, but cumulative loss that may become important if further treatment sessions are indicated.
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Hydration, kidney injury and clinical outcomeEl-Sharkawy, Ahmed M. January 2016 (has links)
Studies in health care professional (HCPs) have demonstrated a high prevalence of dehydration, which has been linked with morphological brain changes as well as cognitive impairment in other groups. Moreover, many age-related pathophysiological changes result in increased susceptibility to fluid and electrolyte imbalance, rendering older adults vulnerable to dehydration which may be associated with poor outcome. This thesis investigates the prevalence of dehydration and impact on cognitive function amongst HCPs. It also investigates the prevalence of dehydration in hospitalised older adults and the association between dehydration, acute kidney injury (AKI) and clinical outcome. Hydration status and cognition were objectively assessed in nurses and doctors working on emergency medical and surgical wards. This study demonstrated that a significant proportion of HCPs were dehydrated at the start and end of their shifts and many were oliguric. The prevalence of dehydration varied with level of experience and speciality and was associated with short-term memory impairment. Using serum osmolality, the key regulated variable in fluid homeostasis as a measure of hydration status in hospitalised older adults, prospective assessment of 200 patients demonstrated that over a third had hyperosmolar dehydration (HD) at admission, two-thirds of which were dehydrated 48 hours later. Dehydration at admission was independently associated with a six-fold increase in 30-day mortality. Subsequent retrospective assessment of 32,980 hospitalised older adults demonstrated that dehydration was diagnosed clinically in 8.9% of patients and was independently associated with a two fold increase in mortality. Nearly half of those dehydrated had a concomitant diagnosis of AKI and the median length of hospital stay (LOS) was nearly three times greater than those without the condition. Despite the widespread use of serum osmolality in human physiology studies, it is rarely used clinically to assess hydration. Analysis of published equations estimating osmolality, demonstrated that an equation by Khajuria and Krahn was 90% sensitivity and 97% specificity at diagnosing hyperosmolar dehydration. Using this equation, we demonstrated that 27.2% of 6632 older adults had HD at admission to hospital and the risk of developing AKI 12-24 hours after admission in these patients was five times those euhydrated at admission. Moreover, the 30-day mortality was nearly twice that of euhydrated patients, independent of key confounders. The median LOS in dehydrated patients was almost double. This work has highlighted the need to educate both patients and HCPs on the importance of hydration. Further work is required to prospectively assess the use of serum osmolality as a predictor of dehydration, AKI and outcomes. Given that hydration and nutrition are the hallmarks of compassionate care, there is clear room for improvement with findings from this thesis suggesting the need for further investigation and intervention in both community and hospital settings.
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Development of MRI techniques for the assessment of chronic kidney diseaseBuchanan, Charlotte E. January 2016 (has links)
It is well established that patients with Chronic Kidney Disease (CKD) are more susceptible to develop cardiovascular disease in comparison to the healthy population. This thesis aims to develop and apply MRI techniques to assess the human heart and kidney in patients with chronic kidney disease (CKD). Magnetic resonance imaging (MRI) can be used to inform on structure, function, perfusion and blood flow, without the need for ionizing radiation. In order to assess blood flow using MRI, gadolinium based contrast agents are often used. Patients with compromised kidney function are contraindicated to these contrast agents and so it is necessary to develop imaging techniques that can be used without a contrast agent. Arterial spin labelling (ASL) is an MRI technique that provides a non-contrast enhanced method to assess tissue perfusion using the intrinsic signal from the water in the body. ASL is now becoming a well-established technique in the brain, however applications of ASL in the body are currently limited. In this work, a cardiac ASL technique is developed using a modified Look-Locker scheme to study the myocardium of the heart. This technique is then applied in patients with CKD Stage 3 and age-matched healthy control subjects to assess the changes in myocardial perfusion during a handgrip exercise challenge. MRI measurements of cardiac index and stroke volume index, global and regional contractile function (myocardial strain), coronary artery flow and myocardial perfusion using ASL are applied to assess changes in cardiac function in CKD Stage 5 patients during dialysis treatment. The measures are performed in a randomised design to assess the cardiovascular effects in patients undergoing both haemodialysis and haemodiafiltration. Finally, a comparison of 2D readout schemes for renal ASL is performed. Gradient and spin echo based readout schemes for multi-slice ASL of the kidney at 3 T are evaluated and directly compared in terms of temporal SNR, image SNR, spatial coverage, perfusion quantification and variability across slices/subjects. This work aims to determine the optimal readout scheme for pulsed ASL (PASL) of the kidneys at 3 T in healthy volunteers with normal renal function. In future work this could be applied to patients with compromised renal function where a robust imaging technique is needed. Finally, a summary of the key findings of this thesis and an outline of the potential future directions of this work is provided.
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The mechanisms and consequences of haemodialysis induced acute cardiac injuryBurton, James O. January 2009 (has links)
Patients on dialysis are subject to a hugely elevated risk of cardiovascular mortality. Incidence and prevalence of, and mortality and morbidity from heart failure is significantly higher in the haemodialysis population than the general population as a whole. This thesis describes research work focusing on the large scale haemodynamic changes that occur during haemodialysis and how they may negatively impact on the cardiovascular system. Our results show that the haemodynamic disturbances which occur during haemodialysis are capable of causing a reduction in myocardial blood flow sufficient in magnitude to induce myocardial ischaemia. This is associated with a matched reduction in regional left ventricular (LV) function and is entirely in keeping with other published work describing haemodialysis induced myocardial stunning reflecting subclinical myocardial ischaemia (myocardial stunning). In addition, we now know that this phenomenon of haemodialysis induced myocardial ischaemia and stunning is common and associated with both short and long term complications including ventricular arrhythmias, left ventricular dysfunction, an increased hazard of death and time to first cardiovascular event. This is pertinent as in non-dialysis patients repeated episodes of myocardial stunning lead to chronic heart failure, and in dialysis patients the presence of LV dysfunction dramatically increases the risk of death. We also identified a number of factors associated with the presence of myocardial stunning including age, raised biochemical markers of cardiac damage (troponin-T), higher ultrafiltration volumes and lower intradialytic blood pressure. This is of crucial importance as ultrafiltration volumes and intradialytic haemodynamics are potentially modifiable risk factors that could provide targets for dialysis based interventions aimed at improving cardiovascular outcomes in the haemodialysis population.
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Structural Validity of the Woodcock Johnson III Cognitive in a Referred SampleJanuary 2012 (has links)
abstract: The structural validity of the WJ-III Cognitive was investigated using the GIA-Extended Battery test scores of 529, six-to-thirteen-year-old students referred for a psychoeducational evaluation. The results of an exploratory factor analysis revealed 11 of the 14 tests loaded on their expected factors. For the factors Gc, Gf, Gs, and Gv, both tests associated with the factor loaded highly; for Gsm, Glr, and Ga, only one test associated with each factor loaded highly. Obtained congruence coefficients supported the similarity between the factors Gs, Gf, Gc, Glr, and Gv for the current referred sample and the normative factor structure. Gsm and Ga were not found to be similar. The WJ-III Cognitive structure established in the normative sample was not fully replicated in this referred sample. The Schmid-Leiman orthogonalization procedure identified a higher-order factor structure with a second-order, general ability factor, g, which accounted for approximately 38.4% of common variance and 23.1% of total variance among the seven, first-order factors. However, g accounted for more variance in both associated tests for only the orthogonal first-order factor Gf. In contrast, the Gc and Gs factors accounted for more variance than the general factor for both of their respective tests. The Gsm, Glr, Ga, and Gv factors accounted for more variance than g for one of the two tests associated with each factor. The outcome indicates Gc, Gf, Gs, and Gv were supported and thus are likely factors that can be utilized in assessment while Gsm, Glr, and Gr were not supported by this study. Additionally, results indicate that interpretation of the WJ-III scores should not ignore the global ability factor. / Dissertation/Thesis / Ph.D. Educational Psychology 2012
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