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Methodologic Limitations (methodologic + limitation)

Distribution by Scientific Domains

Medical Sciences	80%

Selected Abstracts

Unilateral Intracarotid Amobarbital Procedure for Language Lateralization

EPILEPSIA, Issue 11 2005
Jörg Wellmer
Summary:,Purpose: The determination of language dominance as part of the presurgical workup of patients with pharmacoresistant epilepsies has experienced fundamental changes. With the introduction of noninvasive functional magnetic resonance imaging (fMRI), the number of patients receiving intracarotid amobarbital procedures (IAPs) for assessment of language dominance has decreased considerably. However, recent studies show that because of methodologic limitations of fMRI, IAP remains an important tool for language lateralization. The current study examines whether unilateral instead of bilateral IAP is an adequate way to apply IAP with reduced invasiveness. Methods: We retrospectively examine the predictive value of unilateral IAP for the results of bilateral IAP based on a sample of 75 patients with various types of language dominance. Target parameters are the prediction of the language-dominant hemisphere and the identification of patients with atypical language dominance. For language assessment based on unilateral IAP, we introduce the measure hemispheric language capacity (HLC). Results: Unilateral IAP performed on the side of intended surgery quantifies language capacity contralateral to the intended surgery. It detects atypical (bilateral or right) language dominance in the majority of patients. Experience with a separate series of 107 patients requiring presurgical language lateralization shows that in >80%, bilateral IAPs are redundant. Conclusions: Unilateral IAP is principally sufficient for language lateralization in the presurgical evaluation of patients with pharmacoresistant epilepsies. Necessity of bilateral IAP is restricted to few indications (e.g., callosotomy). In times of noninvasive language lateralization, we propose unilateral IAP as the method of choice for the verification of doubtful (bilateral) fMRI activation patterns. [source]

Osteoporosis-Related Kyphosis and Impairments in Pulmonary Function: A Systematic Review,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2007
Robyn A Harrison
Abstract We conducted a systematic review to examine the relationship between osteoporotic vertebral fractures, kyphosis, and pulmonary function. Findings suggest modest but predictable declines in vital capacity related to the degree of kyphosis. However, there were only four studies, and all had significant methodologic limitations. Further high-quality research is needed. Introduction: Our objective was to systematically review the extent to which osteoporosis-related vertebral fractures and kyphosis affect pulmonary function. Materials and Methods: We used a literature search from 1966 to 2006 (using Medline, EMBASE, and hand searches of references) for studies examining pulmonary function in patients without known lung disease who had vertebral fractures or kyphosis secondary to osteoporosis. Two reviewers independently abstracted data. Heterogeneity precluded formal meta-analysis. Results: Initial searches yielded 453 articles. After applying eligibility criteria, only four case-control studies of limited quality (e.g., only one study was blinded) remained. Since 1966, only 109 patients (6 men) have been studied. All four studies reported reductions in vital capacity (VC), with values ranging from 68% to 94% of predicted values. This was quantified as a 9% reduction in predicted VC per vertebral fracture in one study. The degree of kyphosis clinically (one study) or radiographically (three studies) correlated with declines in VC; impairments were most notable at kyphotic angles >55°. Statistically significant differences in percent predicted VC were obtained only when arm span or recalled height, rather than measured height, was used (two studies). Conclusions: Despite conventional teaching, the evidence relating osteoporotic vertebral fractures or kyphosis to pulmonary function is limited. On the basis of available studies, declines in VC secondary to kyphosis seem modest and directly related to the number of vertebral fractures or degree of kyphosis. Future studies need longitudinal follow-up of larger numbers of men and women, appropriate proxies for height, standardized measures for pulmonary function and kyphosis, and efforts to blind outcomes ascertainment. [source]

Toothbrushing Competency Among High-risk Grade One Students: an Evaluation of Two Methods of Dental Health Education

JOURNAL OF PUBLIC HEALTH DENTISTRY, Issue 4 2001
Robert J. Hawkins BSc
Abstract Objective: To evaluate the effectiveness of two methods of dental health education (DHE) for improving toothbrushing competency among grade one students at high risk for dental diseases. Methods: Fifty elementary schools in the former city of North York, Ontario, Canada, were assigned to one of two groups. In one group, students received a classroom-based DHE lesson that was reinforced by two small group sessions (n=243). In the other group, students received only a single classroom-based DHE lesson (n=206). Trained examiners assessed 11 toothbrushing skills at pre- and postintervention. Results: At the preintervention test, few significant differences were found between the groups and many students did not display competency in fundamental oral health skills, such as placing a toothbrush at the gum line. Following DHE interventions, students in both groups demonstrated improvements in most skills. A significantly higher proportion of students who received both classroom and small group sessions displayed gains in competency in three skills, compared to students receiving only a classroom lesson. These skills were brushing anterior lingual surfaces, brushing posterior lingual surfaces, and brushing all areas in a routine fashion. Students receiving only a classroom session did not display greater improvements in any skill areas compared to "classroom plus small group" students. Some students in both groups still lacked fundamental skills at the end of the DHE program. Conclusions: While one must exercise caution in interpreting the results due to several methodologic limitations, findings suggest that for high-risk grade one students, a classroom-based lesson combined with small group sessions is a more effective method of improving toothbrushing skills compared to a single classroom-based lesson. [source]

Systematic Review of Emergency Physician,performed Ultrasonography for Lower-Extremity Deep Vein Thrombosis

ACADEMIC EMERGENCY MEDICINE, Issue 6 2008
Patrick R. Burnside MD
Abstract Objectives:, The authors performed a systematic review to evaluate published literature on diagnostic performance of emergency physician,performed ultrasonography (EPPU) for the diagnosis and exclusion of deep venous thrombosis (DVT). Methods:, Structured search criteria were used to query MEDLINE and EMBASE, followed by a hand search of published bibliographies. Relevance and inclusion criteria required prospective investigation of emergency department (ED) outpatients with suspected DVT; diagnostic evaluations had to consist of EPPU followed by criterion standard (radiology-performed) imaging. Two authors independently extracted data from included studies; study quality was assessed utilizing a validated tool for quality assessment of diagnostic accuracy studies (QUADAS). Pooled data were analyzed using an unweighted summary receiver-operating-characteristic (SROC) curve; sensitivity and specificity were estimated using a random effects model. Results:, The initial search yielded 1,162 publications. Relevance screening and selection yielded six articles including 936 patients. Four of the six studies reported adequate blinding but a number of other methodologic flaws were identified. A random effects model yielded an overall sensitivity of 0.95 (95% confidence interval [CI] = 0.87 to 0.99) and specificity of 0.96 (95% CI = 0.87 to 0.99). Conclusions:, Systematic review of six studies suggests that EPPU may be accurate for the diagnosis of DVT compared with radiology-performed ultrasound (US). However, given the methodologic limitations identified among the primary studies, the estimates of diagnostic test performance may be overly optimistic. Further research into EPPU for suspected DVT is needed before it can be adopted into routine clinical practice. [source]

An evidence-based approach to human dermatomes

CLINICAL ANATOMY, Issue 5 2008
M.W.L. Lee
Abstract The dermatome is a fundamental concept in human anatomy and of major importance in clinical practice. There are significant variations in current dermatome maps in standard anatomy texts. The aim of this study was to undertake a systematic literature review of the available evidence for the distribution of human dermatomes. Particular emphasis was placed on the technique of ascertainment, the location and extent of each dermatome, the number of subjects studied, and methodologic limitations. Our findings demonstrate that current dermatome maps are inaccurate and based on flawed studies. After selecting the best available evidence, a novel evidence-based dermatome map was constructed. This represents the most consistent tactile dermatomal areas for each spinal dorsal nerve root found in most individuals. In addition to highlighting the orderly arrangement, areas of consistency and clinical usefulness of dermatomes, their overlap and variability deserve greater emphasis. This review demonstrates the validity of an evidence-based approach to an anatomical concept. Clin. Anat. 21:363,373, 2008. © 2008 Wiley-Liss, Inc. [source]