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This paper analyses the methodological issues inherent in evaluating healthcare education and considers approaches for addressing these.Recent policies have exhorted practitioners to base their practice on evidence; however in healthcare education the evidence base is not extensive. Whilst educational evaluation has advanced in the last decades, standardised designs and toolkits are not available. Each evaluation has different aims and occurs in specific contexts, thus the design has to fit the circumstances, yet meet the challenge of scientific credibility. Indicators of educational processes and outcomes are not scientifically verified; no toolkit of standardised ‘off-the-shelf’ valid, reliable and sensitive measures exists. The evidence base of educational practice is largely derived from small-scale, single case studies; the majority of measures are self-devised, unvalidated tools of unproven reliability, thus meta-synthesis is not appropriate and results are not generalisable. Healthcare educational evaluators need valid and reliable assessments of both knowledge acquisition and its application to practice. The need to establish and explain attribution, i.e. the relationship between educational inputs and outcomes is complex and requires experimental/quasi-experimental design. In addition, educational evaluators face the pragmatic challenge of practice in healthcare contexts, where confounding variables are hard to control and resources are scarce. 相似文献
3.
Atul K. Sharma Moira S. Mills Vijay L. Grey Keith N. Drummond 《Pediatric nephrology (Berlin, Germany)》1997,11(6):711-713
Accurate, timed urine collections for the measurement of glomerular filtration rate (GFR) may be impractical in infants or
in patients with urological abnormalities. GFR may be measured without urine collection using a constant subcutaneous infusion
of iothalamate. We compare the infusion clearance with conventional renal clearance in 14 children and young adults. The mean
clearance ratio (infusion clearance/renal clearance ± 1 SD) was 0.99±0.1 and the mean discrepancy between the two methods
was 8.5%±4.7%. The 95% limits of agreement for the ratio of the two methods are 0.83–1.23. These data indicate that subcutaneous
infusion of iothalamate is a practical method for measuring GFR in children without a urine collection.
Received March 18, 1996; received in revised form February 12, 1997; accepted March 26, 1997 相似文献
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Heather A McKay Harri Siev?nen Moira A Petit Kerry J MacKelvie Ken M Forkheim Ken P Whittall Bruce B Forster Heather Macdonald 《Journal of clinical densitometry》2004,7(2):161-168
Conventional density measures by dual-energy X-ray absorptiometry (DXA) are confounded by increases in bone size and do not assess bone geometry. We assessed precision of magnetic resonance imaging (MRI) and used MRI, DXA, and hip structure analysis (HSA) to assess 7-mo changes in bone structure at the femoral neck in 18 prepubertal girls. At baseline, girls were 10.4 (0.5) yr, 144.0 (8.2) cm, and 35.2 (7.0) kg, on average. Total bone and cortical cross-sectional area (ToA and CoA) were calculated from high-resolution T1-weighted MRI oblique axial images of the femoral neck. We used proximal femur DXA scans (Hologic QDR-4500) and the HSA program to estimate bone cross-sectional area (CSA), and calculate section modulus. MRI precision was determined by scanning 10 volunteers (13-46 yr old) three times with and without repositioning. Precision (CVrms) was 2% for ToA and 7% for CoA. Significant correlations were observed between FN area and MRI-derived ToA (r = 0.57, p = 0.013) and CoA (r = 0.47, p = 0.050). There were significant positive changes over 7 mo by both methods. In conclusion, MRI provides useful information on femoral neck bone area in children. The reproducibility of cortical dimensions at the femoral neck needs improvement through technical modifications and appropriate analysis software. 相似文献
6.
Michelle K Williamson Jane Pirkis Jon J Pfaff Orla Tyson Moira Sim Ngaire Kerse Nicola T Lautenschlager Nigel P Stocks Osvaldo P Almeida 《BMC medical research methodology》2007,7(1):42
Background
Recruiting and retaining GPs for research can prove difficult, and may result in sub-optimal patient participation where GPs are required to recruit patients. Low participation rates may affect the validity of research. 相似文献7.
McManamny P Chy HS Finkelstein DI Craythorn RG Crack PJ Kola I Cheema SS Horne MK Wreford NG O'Bryan MK De Kretser DM Morrison JR 《Human molecular genetics》2002,11(18):2103-2111
Spinal and bulbar muscular atrophy (SBMA) is an adult-onset motor neuron disease, caused by the expansion of a trinucleotide repeat (TNR) in exon 1 of the androgen receptor (AR) gene. This disorder is characterized by degeneration of motor and sensory neurons, proximal muscular atrophy, and endocrine abnormalities, such as gynecomastia and reduced fertility. We describe the development of a transgenic model of SBMA expressing a full-length human AR (hAR) cDNA carrying 65 (AR(65)) or 120 CAG repeats (AR(120)), with widespread expression driven by the cytomegalovirus promoter. Mice carrying the AR(120) transgene displayed behavioral and motor dysfunction, while mice carrying 65 CAG repeats showed a mild phenotype. Progressive muscle weakness and atrophy was observed in AR(120) mice and was associated with the loss of alpha-motor neurons in the spinal cord. There was no evidence of neurodegeneration in other brain structures. Motor dysfunction was observed in both male and female animals, showing that in SBMA the polyglutamine repeat expansion causes a dominant gain-of-function mutation in the AR. The male mice displayed a progressive reduction in sperm production consistent with testis defects reported in human patients. These mice represent the first model to reproduce the key features of SBMA, making them a useful resource for characterizing disease progression, and for testing therapeutic strategies for both polyglutamine and motor neuron diseases. 相似文献
8.
Mak JC Leung HC Ho SP Law BK Lam WK Tsang KW Ip MS Chan-Yeung M 《The Journal of allergy and clinical immunology》2004,114(2):260-264
BACKGROUND: Patients with asthma generate an increased amount of reactive oxygen species from peripheral blood cells. Reactive oxygen species produce many of the pathophysiologic changes associated with asthma and may contribute to its pathogenesis. OBJECTIVE: We investigated changes in antioxidant enzyme activities and oxidized glutathione (glutathione disulfide; GSSG) levels in erythrocytes from a group of healthy control Chinese subjects (n=135) and patients with asthma (n=106). METHODS: Baseline pulmonary function was measured for all subjects. Antioxidant status was evaluated by measuring erythrocyte superoxide dismutase, catalase, and glutathione peroxidase activities. Oxidative stress was also measured in terms of GSSG in erythrocytes with a kinetic microassay. RESULTS: Patients with asthma had significantly increased erythrocyte superoxide dismutase and catalase activities compared with controls (61.10 +/- 1.30 U/g hemoglobin [Hb] vs 55.51 +/- 1.82 U/g Hb [P=.018] and 0.0637 +/- 0.0021 U/g Hb vs 0.0257 +/- 0.0120 U/g Hb [P <.001] for the asthma and control groups, respectively). Conversely, erythrocyte glutathione peroxidase activity decreased (44.21 +/- 1.33 mU/g Hb vs 50.07 +/- 1.39 mU/g Hb for the asthma and control groups, respectively; P=.003). Patients with asthma also had significantly higher GSSG levels in erythrocyte hemolysates compared with controls (167.40 +/- 2.93 micromol/L vs 44.98 +/- 0.44 micromol/L for the asthma and control groups, respectively; P <.001), indicating increased oxidative stress. CONCLUSIONS: Asthma is accompanied by an alteration in systemic antioxidant status due to possible oxidative stress in this disease. 相似文献
9.
Paul A. Knepper Ralph K. Losey Jennifer A. Collins David G. McLone Hyman G. Weinstein Moira Breen 《Neurobiology of aging》1983,4(2):163-168
The glycosaminoglycan distribution patterns of the cerebrospinal fluid (CSF) outflow pathway, dura mater and cerebral cortex of young New Zealand red rabbits and 1-, 3- and 12-week-old C-57 mice were identified by analyses of the glycosaminoglycan moieties and by the use of zone electrophoresis. The glycosaminoglycans were identified by specific degradation procedures, i.e., hyaluronate lyase, chondroitin ABC lyase, endo-gb-D-galactosidase and nitrous acid treatment. The CSF outflow pathway and dura mater glycosaminoglycan components were primarily hyaluronic acid and chondroitin sulfatedermatan sulfate, whereas the cerebral cortex glycosaminoglycan components were hyaluronic acid, chondroitin sulfatedermatan sulfate, keratan sulfate and heparan sulfate. The glycosaminoglycan components of the dura mater and cerebral cortex decreased and those of the CSF outflow pathway increased as a function of age. These results demonstrate the feasibility of analyses of the CSF outflow pathway glycosaminoglycan components and suggest that topographical changes in the glycosaminoglycan distribution profiles may contribute to the pattern of cerebrospinal fluid outflow. 相似文献
10.
The authors examined the therapeutic alliance in evidence-based treatment for children (N = 185, 47 girls, 138 boys; ages 3-14 years) referred clinically for oppositional, aggressive, and antisocial behavior. Different alliances (child-therapist, parent-therapist) were assessed from each participant's perspective at 2 points over the course of treatment. As predicted, both child-therapist and parent-therapist alliances related to therapeutic change, family experience of barriers to participation in treatment, and treatment acceptability. Greater alliance was associated with greater therapeutic change, fewer perceived barriers, and greater treatment acceptability. The findings could not be attributed to the influence of socioeconomic disadvantage, parent psychopathology and stress, and child dysfunction or to rater effects (common rater variance in the predictors and criteria). 相似文献