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Misinterpretation
Selected AbstractsGynaecological presentation of retroperitoneal tumoursBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 2 2000Andrew J. Spillane Fellow (Surgical Oncology) Objective To illustrate the problems associated with mistaken pre-operative diagnosis following gynaecological presentation of patients with retroperitoneal tumours. Design A case series of five referrals. Results Non-gynaecological tumours were not suspected in each case and hence there was a failure to undertake further pre-operative investigation and referral to a specialised soft tissue sarcoma service. This resulted in four of the patients having an unnecessary laparotomy with an inappropriate transperitoneal biopsy undertaken when the retroperitoneal tumour was discovered. The mistaken diagnosis of ovarian malignancy lead to increased morbidity, compromise of potential for a long disease free interval and/or possibly lessened the chance of cure in each case. Conclusions Misinterpretation of clinical signs and an over-reliance on ultrasound diagnosis were the commonest causes of inappropriate management of these patients. Gynaecologists should consider more frequently the other, less common differential diagnoses of a pelvic mass. This is especially true in circumstances with a predominantly solid tumour, where there are clinical signs of vascular or rectal displacement, or where there is ultrasound evidence of ureteric obstruction. The more frequent utilisation of a computerised tomography scan with intravenous and oral contrast with referral before inappropriate transperitoneal biopsy are recommended as complete en bloc surgical excision at the first laparotomy is the treatment of choice in virtually all primary retroperitoneal tumours. [source] Strong irritants masquerading as skin allergens: the case of benzalkonium chlorideCONTACT DERMATITIS, Issue 4 2004David A. Basketter Chemicals may possess a number of hazards to human health including the ability to cause skin irritation and contact allergy. Identification and characterization of these properties should fall within predictive toxicology, but information derived from human exposure, including clinical experience, is also of importance. In this context, it is of interest to review the case of benzalkonium chloride, a cationic surfactant. This chemical is a well-known skin irritant, but on occasions it has also been reported to have allergenic properties, typically on the basis of positive diagnostic patch test data. Because the accumulated knowledge concerning the properties of a chemical is employed as the basis for its regulatory classification (e.g. in Europe), as well as for informing the clinical community with respect to the diagnosis of irritant versus allergic contact dermatitis (ACD), it is important to distinguish properly which chemicals are simply irritants from those which are both irritant and allergenic on skin. A review of the information on benzalkonium chloride confirms that it is a significant skin irritant. However, both predictive test results and clinical data lead to the conclusion that benzalkonium chloride is, at most, an extremely rare allergen, except perhaps in the eye, but with many supposed cases of ACD being likely to arise from the misinterpretation of patch test data. As a consequence, this substance should not normally be regarded as, or classified as, a significant skin sensitizer. [source] An exploration of research into substance misuse and psychiatric disorder in the UK: what can we learn from history?CRIMINAL BEHAVIOUR AND MENTAL HEALTH, Issue 4 2007Ilana B. Crome Background and aim,This review explores UK-based research developments in substance misuse and mental illness over the last 25 years. The main body of work comprises policy-orientated projects funded by the Department of Health from the late 1990s. Early research tended to focus on alcohol, especially alcoholic hallucinosis: the relationship of the latter with schizophrenia-like illness was examined, with the finding that very few cases did develop into schizophrenia. Method and implications,Parallels are drawn with the current debate around the link between cannabis and psychosis, urging caution in too rapid an assertion that cannabis is necessarily ,causal'. The clinical and policy implications of the misinterpretation of evidence are discussed. A proposal is put forward that the genesis of psychotic illness in alcohol misuse be revisited using more sophisticated research methodologies. Given the changing landscape of substance use in the UK, particularly the fashion of polysubstance use and the recognition that this is associated with psychotic illness, other drugs that are associated with psychotic illness should be similarly investigated to determine whether there is a common mechanism that might throw light on understanding the relationship between substance use and psychotic illness or schizophrenia. Copyright © 2007 John Wiley & Sons, Ltd. [source] Intraoperative diagnosis of tanycytic ependymoma: Pitfalls and differential diagnosisDIAGNOSTIC CYTOPATHOLOGY, Issue 4 2001Marc A. Dvoracek M.D. Abstract Smear preparations have become increasingly popular in the intraoperative assessment of central nervous system pathology. The cytological features of a histologically proven tanycytic ependymoma are presented with the pitfalls and differential diagnosis. The smear preparation showed a glial neoplasm composed of cells with long, bipolar glial processes and oval to spindle-shaped nuclei resembling those seen in pilocytic astrocytoma smears. The smear characteristics of an ependymoma usually show remarkably uniform round-to-oval nuclei, fluffy glial processes, and a perivascular nuclear-free zone (pseudorosetting). None of these features were present in our case. The accompanying frozen section showed a fascicular spindle-cell tumor that resembled a schwanomma, a commonly reported misinterpretation of the histology of tanycytic ependymomas on frozen sections. Careful attention to the radiological findings, the surgeon's impression, and the intraoperative smear preparation details should allow one to include this uncommon entity in the differential diagnosis of spinal neoplasms. Diagn. Cytopathol. 24:289,292, 2001. © 2001 Wiley-Liss, Inc. [source] Accounting for uncertainty in DEMs from repeat topographic surveys: improved sediment budgetsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2010Joseph M. Wheaton Abstract Repeat topographic surveys are increasingly becoming more affordable, and possible at higher spatial resolutions and over greater spatial extents. Digital elevation models (DEMs) built from such surveys can be used to produce DEM of Difference (DoD) maps and estimate the net change in storage terms for morphological sediment budgets. While these products are extremely useful for monitoring and geomorphic interpretation, data and model uncertainties render them prone to misinterpretation. Two new methods are presented, which allow for more robust and spatially variable estimation of DEM uncertainties and propagate these forward to evaluate the consequences for estimates of geomorphic change. The first relies on a fuzzy inference system to estimate the spatial variability of elevation uncertainty in individual DEMs while the second approach modifies this estimate on the basis of the spatial coherence of erosion and deposition units. Both techniques allow for probabilistic representation of uncertainty on a cell-by-cell basis and thresholding of the sediment budget at a user-specified confidence interval. The application of these new techniques is illustrated with 5 years of high resolution survey data from a 1,km long braided reach of the River Feshie in the Highlands of Scotland. The reach was found to be consistently degradational, with between 570 and 1970,m3 of net erosion per annum, despite the fact that spatially, deposition covered more surface area than erosion. In the two wetter periods with extensive braid-plain inundation, the uncertainty analysis thresholded at a 95% confidence interval resulted in a larger percentage (57% for 2004,2005 and 59% for 2006,2007) of volumetric change being excluded from the budget than the drier years (24% for 2003,2004 and 31% for 2005,2006). For these data, the new uncertainty analysis is generally more conservative volumetrically than a standard spatially-uniform minimum level of detection analysis, but also produces more plausible and physically meaningful results. The tools are packaged in a wizard-driven Matlab software application available for download with this paper, and can be calibrated and extended for application to any topographic point cloud (x,y,z). Copyright © 2009 John Wiley & Sons, Ltd. [source] Laboratory simulation of clast abrasionEARTH SURFACE PROCESSES AND LANDFORMS, Issue 2 2002J. Lewin Abstract Experimental abrasion of river-bed materials has been widely undertaken, producing ,downstream' fining rates that generally are believed to be much less than those observed in the field. A conclusion commonly adopted has been that sorting processes are more effective than abrasion processes. A comparative evaluation of results from an abrasion tank and a tumbling barrel are presented, which show that abrasion patterns and rates differ according to the equipment used, clast size and shape, the clast charge (barrel) and water velocity and bed material (tank). Abrasion is a composite process, and the effects achieved appear to be dominated by percussion in the tank and grinding in the barrel. Breakage, crushing and sandblasting are not modelled effectively, nor are effects achieved on clasts when they form part of the bed. Comparisons are made with other equipment used, the very limited amount of direct field abrasion monitoring, and with the probable suite of processes that may occur under field conditions. Also reviewed are the problems that arise when laboratory weight-loss abrasion coefficients are used or converted into ones of size diminution, as usually derived from field observations of down-channel trends. It is concluded that field abrasion rates generally have been underestimated, as the processes involved are at best only selectively represented by the experimental equipment so far used, and because the results obtained experimentally are capable of misinterpretation when related to field trends. Copyright © 2002 John Wiley & Sons, Ltd. [source] Diagnostic Accuracy of Handheld Echocardiography for Evaluation of Aortic StenosisECHOCARDIOGRAPHY, Issue 5 2010Arnd Schaefer M.D. Background: Symptomatic severe aortic stenosis is associated with increased mortality and morbidity. Early identification of these patients by echocardiography is crucial. We conducted this study to evaluate a handheld ultrasound device (HCU) in patients with suspected severe aortic stenosis (AS) in comparison to a standard echocardiography device (SE). Methods: A HCU (Vivid I; GE Healthcare) and a SE device (Philips iE 33) were used to evaluate 50 consecutive patients with suspected severe AS. Two consecutive echocardiographic studies were performed by two experienced and blinded examiners using HCU and SE device. AS was graded by mean transaortic pressure, aortic valve area (AVA), and indexed AVA (AVA adjusted for body surface area). Results: Mean difference for mean transaortic gradient, AVA and indexed AVA for the SE and HCU device were 1.28 mmHg (,0.70 to 3.26 mmHg), ,0.02 cm2 (,0.06 to 0.01 cm2), and ,0.01 cm2/m2 (,0.03 to 0.01 cm2/m2), respectively. Discrepancies between both devices were not associated with misinterpretation of the degree of AS. Conclusion: Our study demonstrates that HCU can be used to evaluate patients with suspected AS. (ECHOCARDIOGRAPHY 2010;27:481-486) [source] Protocol for Optimal Detection and Exclusion of a Patent Foramen Ovale Using Transthoracic Echocardiography with Agitated Saline MicrobubblesECHOCARDIOGRAPHY, Issue 7 2006Robert R. Attaran M.B.Ch.B. Agitated saline bubble studies in conjunction with echocardiography, in particular transesophageal echocardiography, are currently the principal means in the diagnosis of patent foramen ovale (PFO). We describe techniques and guidelines for the detection and exclusion of a PFO. The potential for misinterpretation of these bubble studies exists and therefore, several false positive and false negative scenarios are illustrated and discussed. [source] Knowing Truth: Peirce's epistemology in an educational contextEDUCATIONAL PHILOSOPHY AND THEORY, Issue 2 2005Christine L. McCarthy Abstract In this paper I examine Peirce's epistemological and ontological theories and indicate their relevance to educational practice. I argue that Peirces conception of Firsts, Seconds and Thirds entails a fundamental ontological realism. I further argue that Peirce does have a theory of truth, that it is a particular non-traditional ,correspondence' theory, consistent with, and implicit in, an over-arching position of pragmatic realism. Peirce's epistemological position is subject to misinterpretation when the ontological realism on which it rests is overlooked. Finally I suggest that such a re-consideration of Peirce's pragmatic ontology and epistemology in an educational context is needed. [source] The Influence of Electrode Porosity on Diffusional Cyclic VoltammetryELECTROANALYSIS, Issue 22 2008Denis Menshykau Abstract A simple generic model to predict the influence of electrode porosity on the cyclic voltammetric response of an electrode is presented. The conditions under which deviation from the behavior of a perfectly flat, planar electrode can be expected are predicted. The scope for misinterpretation when conventional flat electrode theory is applied to porous electrodes is highlighted, especially in respect to the extraction of electrode kinetic parameters and the influence of ,electrocatalysis'. [source] Can late summer Landsat data be used for locating Asian migratory locust, Locusta migratoria migratoria, oviposition sites in the Amudarya River delta, Uzbekistan?ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2008Ramesh Sivanpillai Abstract Existing survey methods for assessing the Asian migratory locust, Locusta migratoria migratoria L. (Orthoptera: Acrididae), infestation risk in the Amudarya River delta, Uzbekistan, are largely constrained by economic resources and site accessibility. The surveys are restricted to a few easily accessible areas, which leads to a misinterpretation of the threat of locust infestation. This often results in indiscriminate blanket treatments of vast areas of wetlands with broad-spectrum insecticides, which may adversely impact non-target fauna and flora. In order to minimize the bias during surveys, one approach would be to allocate the sampling locations based on the distribution of the primary food and shelter plant of the locusts, the common reed, Phragmites australis (Cav.) Trin. ex Steud (Poaceae). In this study, we evaluated the utility of satellite-based remotely sensed data (Landsat TM) acquired in August 2006 to characterize reed distribution in the delta and identify potential locust oviposition sites. The overall accuracy of the Landsat data to map land cover classes in the delta was 84%. The Landsat TM data identified 90% of the reeds, but it was less useful in identifying areas where other vegetations (shrubs and grasses) were mixed with reeds. During the following summer field survey in June 2007, we identified 37 sites that were infested with early-instar locusts. The low migration capacity of young nymphs in dense reed vegetation allowed us to presume that these sites were used for oviposition in the previous summer. Twenty-eight (74%) of these 37 sites had reeds in the previous year. Results from these studies demonstrate that reed distribution maps derived from satellite data could be used for targeting locust egg-pod survey locations, in order to minimize sampling bias while predicting locust infestation risks for the following season. [source] Lessons from leeches: a call for DNA barcoding in the labEVOLUTION AND DEVELOPMENT, Issue 6 2006Alexandra E. Bely SUMMARY Many evolution of development labs study organisms that must be periodically collected from the wild. Whenever this is the case, there is the risk that different field collections will recover genetically different strains or cryptic species. Ignoring this potential for genetic variation may introduce an uncontrolled source of experimental variability, leading to confusion or misinterpretation of the results. Leeches in the genus Helobdella have been a workhorse of annelid developmental biology for 30 years. Nearly all early Helobdella research was based on a single isolate, but in recent years isolates from multiple field collections and multiple sites across the country have been used. To assess the genetic distinctness of different isolates, we obtained specimens from most Helobdella laboratory cultures currently or recently in use and from some of their source field sites. From these samples, we sequenced part of the mitochondrial gene cytochrome oxidase I (COI). Sequence divergences and phylogenetic analyses reveal that, collectively, the Helobdella development community has worked on five distinct species from two major clades. Morphologically similar isolates that were thought to represent the same species (H. robusta) actually represent three species, two of which coexist at the same locality. Another isolate represents part of a species complex (the "H. triserialis" complex), and yet another is an invasive species (H. europaea). We caution researchers similarly working on multiple wild-collected isolates to preserve voucher specimens and to obtain from these a molecular "barcode," such as a COI gene sequence, to reveal genetic variation in animals used for research. [source] Effects of hydrogeomorphic region, catchment storage and mature forest on baseflow and snowmelt stream water quality in second-order Lake Superior Basin tributariesFRESHWATER BIOLOGY, Issue 5 2003Naomi E. Detenbeck SUMMARY 1. In this study we predict stream sensitivity to non-point source pollution based on the non-linear responses of hydrological regimes and associated loadings of non-point source pollutants to catchment properties. We assessed two hydrologically based thresholds of impairment, one for catchment storage (5,10%) and one for mature forest (<50% versus >60% of catchment in mature forest cover) across two different hydrogeomorphic regions within the Northern Lakes and Forest (NLF) ecoregion: the North Shore [predominantly within the North Shore Highlands Ecological Unit] and the South Shore (predominantly within the Lake Superior Clay Plain Ecological Unit). Water quality samples were collected and analysed during peak snowmelt and baseflow conditions from 24 second-order streams grouped as follows: three in each region × catchment storage × mature forest class. 2. Water quality was affected by a combination of regional influences, catchment storage and mature forest. Regional differences were significant for suspended solids, phosphorus, nitrogen: phosphorus ratios, dissolved organic carbon (DOC) and alkalinity. Catchment storage was significantly correlated with dissolved silica during the early to mid-growing season, and with DOC, specific conductance and alkalinity during all seasons. Total nitrogen and dissolved nitrogen were consistently less in low mature forest than in high mature forest catchments. Catchment storage interacted with the influence of mature forest for only two metrics: colour and the soluble inorganic nitrogen : phosphorus ratio. 3. Significant interaction terms (region by mature forest or region by storage) suggest differences in regional sensitivity for conductance, alkalinity, total organic carbon, and colour, as well as possible shifts in thresholds of impact across region or mature forest class. 4. Use of the NLF Ecoregion alone as a basis for setting regional water quality criteria would lead to the misinterpretation of reference condition and assessment of condition. There were pronounced differences in background water quality between the North and South Shore streams, particularly for parameters related to differences in soil parent material and glacial history. A stratified random sampling design for baseflow and snowmelt stream water quality based on both hydrogeomorphic region and catchment attributes improves assessments of both reference condition and differences in regional sensitivity. [source] Human-caused stratigraphic mixing of a coastal Hawaiian midden during prehistory: Implications for interpreting cultural depositsGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 5 2010Sasiphan Khaweerat Archaeologists rely on the spatial and temporal distribution of artifacts and other site-based materials to understand the stratigraphic integrity of the matrix in which remains are embedded. Although they are aware of taphonomic and site formation processes that can cause post-depositional movement of objects, misinterpretation can occur. We used high-precision 230Th dating of branch corals found throughout cultural layers of a coastal Hawaiian midden to identify the effects of post-depositional disturbances to the archaeological record. Fifteen corals distributed in three cultural layers of a Mo'omomi bay site on west Moloka'i, Hawaiian Islands, were 230Th dated between A.D. 1513 and A.D. 1623. Even though the cultural layers appeared visually intact, the positions of the dated coral samples indicate stratigraphic mixing as there is no positive age,depth correlation. Consequently, all cultural layers should be considered one analytical unit for analysis of contents. This study is applicable to other Pacific archaeological sites, especially throughout Hawaii and East Polynesia generally, that have well-preserved branch coral for 230Th dating. © 2010 Wiley Periodicals, Inc. [source] Indigenous Methodologies: Suggestions for Junior ResearchersGEOGRAPHICAL RESEARCH, Issue 1 2010NAOHIRO NAKAMURA Abstract Indigenous methodologies in geography have recently been developed to decolonise Western dominated paradigms. It has been argued that research which does not benefit Indigenous communities should not be conducted. However, Indigenous methodologies are not taught in many post-secondary institutions. Therefore, when they pursue Indigenous topics, many junior researchers are self-taught in these methodologies. However, these methodologies cannot be defined simply and they are too diverse to be learnt in a short period. In Japan, Indigenous peoples are not widely recognised and research on contemporary Indigenous issues is limited. The concept of Indigenous methodologies is rarely discussed. Because of this, Japanese researchers rarely identify their research as adopting an Indigenous methodology. Indigenous researchers are thereby discouraged from pursuing Indigenous methodologies. Furthermore, a methodology or a thesis statement used by researchers to reflect Indigenous perspectives often gets little support from Indigenous peoples. My master's research on the Ainu mirrored this situation. While Indigenous methodologies remain difficult to learn, junior researchers should not be discouraged from this form of engagement. Practical suggestions are therefore necessary to encourage their use and application. Based on my experience, I suggest that researchers approach Indigenous communities from a learning perspective. This would encourage open-mindedness and sensitivity. Researchers should also be prepared and willing to refine their research questions and to continue their literature searches after their fieldwork is completed. These strategies could limit misinterpretation and exploitation of Indigenous knowledges and peoples. [source] Functional connexin "hemichannels": A critical appraisalGLIA, Issue 7 2006David C. Spray Abstract "Hemichannels" are defined as the halves of gap junction channels (also termed connexons) that are contributed by one cell; "hemichannels" are considered to be functional if they are open in nonjunctional membranes in the absence of pairing with partners from adjacent cells. Several recent reviews have summarized the blossoming literature regarding functional "hemichannels", in some cases encyclopedically. However, most of these previous reviews have been written with the assumption that all data reporting "hemichannel" involvement really have studied phenomena in which connexons actually form the permeability or conductance pathway. In this review, we have taken a slightly different approach. We review the concept of "hemichannels", summarize properties that might be expected of half gap junctions and evaluate the extent to which the properties of presumptive "hemichannels" match expectations. Then we consider functions attributed to hemichannels, provide an overview of other channel types that might fulfill similar roles and provide sets of criteria that might be applied to verify involvement of connexin hemichannels in cell and tissue function. One firm conclusion is reached. The study of hemichannels is technically challenging and fraught with opportunities for misinterpretation, so that future studies must apply rigorous standards for detection of hemichannel expression and function. At the same time there are reasons to expect surprises, including the possibility that some time honored techniques for studying gap junctions may prove unsuitable for detecting hemichannels. We advise hemichannel researchers to proceed with caution and an open mind. © 2006 Wiley-Liss, Inc. [source] Desertification in the Sahel: a reinterpretation of a reinterpretationGLOBAL CHANGE BIOLOGY, Issue 7 2007STEPHEN D. PRINCE Abstract In semiarid regions the ratio of annual net primary production to precipitation, rain-use efficiency (RUE), has been used as an index of desertification. In a recent publication (Hein & de Ridder, 2006) it was proposed that an incorrect understanding of the relationship between RUE and rainfall has led to a misinterpretation of the satellite record of desertification in the African Sahel. Here, we examine this suggestion and show that, contrary to Hein and de Ridder's statement, satellite studies of Sahelian RUE have reported increases, decreases, and constant values since 1981. Furthermore, we find that data do not support their proposal that RUE increases with rainfall, even in nondegraded areas. Hence we reject their corollary, that constant RUE is prima facie evidence of desertification. The fundamental difficulty with the use of RUE for detection of desertification remains, that is the difficulty of estimation of the RUE for nondegraded land at a regional scale. [source] Cautionary tales in the interpretation of systematic reviews of therapy trialsINTERNAL MEDICINE JOURNAL, Issue 9 2006I. Scott Abstract This is the second in a series of articles emphasizing the cautions in the interpretation of health-care studies. Systematic reviews are presented as comprehensive, unbiased summaries of evidence and are often referred to by clinicians, guideline developers and health policy-makers. Their strengths and limitations, and how their results can be subject to bias and misinterpretation, are discussed. [source] Performance measurement in mental health care: present situation and future possibilitiesINTERNATIONAL JOURNAL OF HEALTH PLANNING AND MANAGEMENT, Issue 3 2010Irma J. Baars Abstract This paper describes performance measurement and its indicators for mental health care services. Performance measurement can serve several goals such as accountability, quality improvement and performance management. For all three purposes structure, process and outcome indicators should be measured. Literature was retrieved from Medline and PsychInfo in order to see which performance indicators were used for the three purposes of performance measurement in mental health care. The indicators were classified in structure, process and outcome indicators. The results show no big differences in the indicators used among studies. Performance management is the performance measurement purpose most referred to, followed by accountability, and quality improvement. Outcome and process indicators are used most, structure indicators are in the minority. Several levels of measurement, that is national or service level, came forward in the literature review. To overcome misinterpretation of data and to be able to improve quality and manage performances, performance indicator sets should refer to structure, process and outcome. Indicators should be chosen carefully with the aim of the measurement taken into mind. Based on this review, a conceptual framework is presented to support managers in their decisions about which indictors can best be used for performance measurement. Additionally, a model that provides an understanding of the use of information gained by performance measurement is given. Copyright © 2009 John Wiley & Sons, Ltd. [source] The influence of education on the interpretation of pharmaceutical pictograms for communicating medicine instructionsINTERNATIONAL JOURNAL OF PHARMACY PRACTICE, Issue 1 2003Ros Dowse senior lecturer Objective To assess the influence of formal education on the interpretation of pharmaceutical pictograms. Method A total of 46 pictograms were used: 23 were extracted directly from the USP-DI, and 23 with corresponding meanings were designed in accordance with the local culture (local pictograms). One hundred and thirty Xhosa respondents, who ranged from having no formal education to tertiary level education, were interviewed with the aid of an interpreter. Demographic data were collected, a literacy test was conducted and respondents were tested for their interpretation of all 46 pictograms. Preference for either the USP-DI or the local pictogram was determined. Setting Respondents were interviewed in primary health care clinics, a variety of work settings or in their homes in Grahamstown, South Africa. Key findings Standard of education had a significant influence on the interpretation of 24 of the 46 pictograms. Generally, significant differences in interpretation were apparent between those with only primary school education and those who had completed at least some senior school education (P < 0.05). The group with tertiary education was significantly better than the other groups (P < 0.05). Only 15 of the 46 pictograms met the American National Standards Institute (ANSI) 85% correct criterion. Conclusion Interpretation was dependent on education and the development of visual literacy skills, but potential for misinterpretation in all educational groups was noted. These results suggest that pictograms should only be used as a communication aid in combination with text or verbal information from the health care provider. [source] Pitfalls of Ability ResearchINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 4 2001Thomas R. Carretta Ability research in psychology can be fraught with pitfalls that lead to inappropriate conclusions. We identify several issues that lead to potential misinterpretation of results and suggest corrective solutions. These issues include lack of construct validity of the measures, misinterpretation of correlations and regression weights, lack of statistical power, failure to estimate cross-validation effects, and misinterpretation of factor analytic results. [source] No Easy Choices: Estimating the Effects of United Nations Peacekeeping (Response to King and Zeng)INTERNATIONAL STUDIES QUARTERLY, Issue 1 2007NICHOLAS SAMBANIS In a study published in the American Political Science Review, we argued that United Nations peace operations have had a positive effect on peacebuilding processes after civil war and presented empirical evidence in support of our claim. Gary King and Langche Zeng have criticized our conclusions for being dependent on indefensible theoretical assumptions and unsupported by the empirical evidence. We show that their critique is based on a misinterpretation of our arguments, that our results are robust to alternative econometric assumptions, that their diagnostic tools cannot be meaningfully applied to our data and that they cannot be used to establish the validity of counterfactual inference. [source] Unifocal Langerhans cell histiocytosis of the oral mucosaJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 7 2009Susanna Fistarol Summary A 24-year-old man was admitted for a painful gingival ulcer. Histology and immunohistochemistry of a lesional biopsy revealed the diagnosis of Langerhans cell histiocytosis (LCH). To rule out multifocal disease, a complete staging was performed. There was no evidence of bony lesions or any other organ involvement. The diagnosis of LCH restricted to the oral mucosa was established. The complete oral lesion was ablated by CO2 laser and subsequently treated topically with triamcinolone acetonide. The patient is still in remission after one year of follow-up. LCH confined to the oral mucosa is rare. It presents usually as an inflammatory or ulcerative lesion, easily leading to misinterpretation and delayed diagnosis. Patients with limited unifocal mucocutaneous disease, as in the present case, usually have an excellent prognosis. However, the oral lesion may represent an early sign of LCH, predating and progressing to an aggressive life-threatening multiorgan disease. [source] Directional asymmetry of long-distance dispersal and colonization could mislead reconstructions of biogeographyJOURNAL OF BIOGEOGRAPHY, Issue 5 2005Lyn G. Cook Abstract Aim, Phylogenies are increasingly being used to attempt to answer biogeographical questions. However, a reliance on tree topology alone has emerged without consideration of earth processes or the biology of the organisms in question. Most ancestral-state optimization methods have inherent problems, including failure to take account of asymmetry, such as unequal probabilities of losses and gains, and the lack of use of independent cost estimates. Here we discuss what we perceive as shortcomings in most current tree-based biogeography interpretation methods and show that consideration of processes and their likelihoods can turn the conventional biogeographical interpretation on its head. Location, Southern hemisphere focus but applicable world-wide. Methods, The logic of existing methods is reviewed with respect to their adequacy in modelling processes such as geographical mode of speciation and likelihood of dispersal, including directional bias. Published reconstructions of dispersal of three plant taxa between Australia and New Zealand were re-analysed using standard parsimony and maximum likelihood (ML) methods with rate matrices to model expected asymmetry of dispersal. Results, Few studies to date incorporate asymmetric dispersal rate matrices or question the simplistic assumption of equal costs. Even when they do, cost matrices typically are not derived independently of tree topology. Asymmetrical dispersal between Australia and New Zealand could be reconstructed using parsimony but not with ML. Main conclusions, The inadequacy of current models has important consequences for our interpretation of southern hemisphere biogeography, particularly in relation to dispersal. For example, if repeated directional dispersals and colonization in the direction of prevailing winds have occurred, with intervening periods of speciation, then there is no need to infer dispersals against those winds. Failure to take account of directionality and other biases in reconstruction methods has implications beyond the simple misinterpretation of the biogeography of a taxonomic group, such as calibration of molecular clocks, the dating of vicariance events, and the prioritization of areas for conservation. [source] Heart rate variability does not tap putative efficacy of Thought Field TherapyJOURNAL OF CLINICAL PSYCHOLOGY, Issue 10 2001John P. Kline Callahan (2001) has offered a series of case reports in an effort to validate the rationale and methods of Thought Field Therapy (TFT). These case reports employ subjective ratings, that is, the Subjective Units of Distress (SUD) rating scale as well as a gross measure of heart rate variability (HRV). My criticisms center around (a) inappropriately strong inferences given exclusive reliance on case reports, a potentially biased sample, and lack of appropriate controls; (b) misinterpretation of statistical artifact as systematic effect; (c) lack of systematic evaluation of HRV changes; and (d) erroneous interpretation of HRV. Callahan's article provides no evidence for the efficacy of TFT nor does it provide evidence for the credibility of TFT's rationale. © 2001 John Wiley & Sons, Inc. J Clin Psychol 57: 1187,1192, 2001. [source] The relationship between history of violent and criminal behavior and recognition of facial expression of emotions in men with schizophrenia and schizoaffective disorderAGGRESSIVE BEHAVIOR, Issue 3 2006Elisabeth M. Weiss Abstract Social psychological research underscores the relation between aggression and emotion. Specifically, regulating negative affect requires the ability to appraise restraint-producing cues, such as facial signs of anger, fear and other emotions. Individuals diagnosed with major mental disorders are more likely to have engaged in violent behavior than mentally healthy members of the same communities. We examined whether violent and criminal behavior in men with schizophrenia is related to emotion recognition abilities. Forty-one men with schizophrenia underwent a computerized emotion discrimination test presenting mild and extreme intensities of happy, sad, angry, fearful and neutral faces, balanced for gender and ethnicity. History of violence was assessed by the Life History of Aggression Scale and official records of arrests. Psychopathology was rated using the Positive and Negative Symptom Scale. Criminal behavior was associated with poor emotion recognition, especially for fearful and angry facial expressions. History of aggression was also associated with more severe positive symptoms and less severe negative symptoms. These findings suggest that misinterpretation of social cues such as angry and fearful expression may lead to a failure in socialization and adaptive behavior in response to emotional situation, which may result in a higher number of criminal arrests. Aggr. Behav. 32:1,8, 2006. © 2006 Wiley-Liss, Inc. [source] Effects of the wood extractive betulinol and 17, -oestradiol on reproduction in zebrafish, Danio rerio (Hamilton) , complications due to a bacterial infectionJOURNAL OF FISH DISEASES, Issue 5 2004I Christianson-Heiska Abstract Zebrafish were exposed to the wood extractive betulinol (5 ,g L,1) and to 17, -oestradiol (E2, 0.27 ,g L,1) for 8 weeks in an attempt to study the possible endocrine-disrupting activity of betulinol. Females exposed to betulinol showed increased spawning intensity, while males exposed to betulinol and E2 had increased incidences of structural alterations in the testes. However, histological examination of the fish revealed that they were infected by acid-fast bacteria suspected to be Mycobacterium sp. despite a careful examination of their health state prior to the onset of the experiment. Fish exposed to betulinol and E2 showed more serious consequences of the bacterial infection than control fish indicating that the test chemicals had weakened the immune defence of the fish. When the exposure was repeated with healthy fish, an increase in the proportion of spermatogonia was seen in the testes of betulinol-treated males. A similar alteration, although not statistically significant, was also seen in the first experiment. However, no increase in the incidences of structural alterations in the testes was seen in betulinol- and E2-treated fish in the second experiment. Our study indicates that betulinol might have an endocrine-disrupting effect in zebrafish, but the increase in incidences of structural alterations in the testes might have been caused by a synergistic action between the test compounds and the bacterial infection. Our study stresses the importance of carefully checking the health of experimental fish, not only prior to the onset of an experiment but also upon termination of the experiment, in order to avoid misinterpretation of the results. [source] Imaging of adenomyomatosis of the gall bladderJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2008H Stunell Summary Adenomyomatosis is a relatively common abnormality of the gall bladder, with a reported incidence of between 2.8 and 5%. Although mainly confined to the adult study group, a number of cases have been reported in the paediatric study group. It is characterized pathologically by excessive proliferation of the surface epithelium and hypertrophy of the muscularis propria of the gall bladder wall, with invagination of the mucosa into the thickened muscularis forming the so-called ,Rokitansky,Aschoff' sinuses. The condition is usually asymptomatic and is often diagnosed as an incidental finding on abdominal imaging. The radiological diagnosis is largely dependent on the visualization of the characteristic Rokitansky,Aschoff sinuses. As the condition is usually asymptomatic, the importance of making a correct diagnosis is to prevent misinterpretation of other gall bladder conditions such as gall bladder cancer, leading to incorrect treatment. In the past, oral cholecystography was the main imaging method used to make this diagnosis. In most institutions, oral cholecystography is no longer carried out, and the diagnosis is now more commonly seen on cross-sectional imaging. In this review article, we describe the manifestations of adenomyomatosis on the various imaging methods, with an emphasis on more modern techniques such as magnetic resonance cholangiopancreatography. A brief section on oral cholecystography to aid readers familiar with this technique in understanding the comparable imaging features on more modern imaging techniques is included. [source] Multicentre quality assurance of intensity-modulated radiation therapy plans: A precursor to clinical trialsJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 5 2007MJ Williams Summary A multicentre planning study comparing intensity-modulated radiation therapy (IMRT) plans for the treatment of a head and neck cancer has been carried out. Three Australian radiotherapy centres, each with a different planning system, were supplied a fully contoured CT dataset and requested to generate an IMRT plan in accordance with the requirements of an IMRT-based radiation therapy oncology group clinical trial. Plan analysis was carried out using software developed specifically for reviewing multicentre clinical trial data. Two out of the three plans failed to meet the prescription requirements with one misinterpreting the prescription and the third failed to meet one of the constraints. Only one plan achieved all of the dose objectives for the critical structures and normal tissues. Although each centre used very similar planning parameters and beam arrangements the resulting plans were quite different. The subjective interpretation and application of the prescription and planning objectives emphasize one of the many difficulties in carrying out multicentre IMRT planning studies. The treatment prescription protocol in a clinical trial must be both lucid and unequivocally stated to avoid misinterpretation. Australian radiotherapy centres must show that they can produce a quality IMRT plan and that they can adhere to protocols for IMRT planning before using it in a clinical trial. [source] Hematology and serum chemistry parameters in juvenile cynomolgus monkeys (Macaca fascicularis) of Mauritius origin: comparison between purpose-bred and captured animalsJOURNAL OF MEDICAL PRIMATOLOGY, Issue 4 2009Ugo Bonfanti Abstract Background, The vast majority of non-human primates used for experimental activities are purpose-bred. However, in case of particular procedures or specific projects, it may still be necessary to use animals captured in the wild. Methods, Sixty cynomolgus monkeys were randomly selected on the basis of breeding origin, and assigned to two groups, each of fifteen males and fifteen females. Analyses included the most frequently investigated parameters for hematology, coagulation, and biochemistry. Results, Differences were observed in some parameters, particularly in eosinophils, basophils and monocytes, and in fibrinogen, total protein, globulins, alanine amino-transferase, creatinine, aspartate amino-transferase, alkaline phosphatase, ,-glutamyl transferase, lactate dehydrogenase, ,-hydroxybutyrate dehydrogenase, iron, potassium, and phosphorus. Conclusions, Some values in the cynomolgus monkey may show significant differences according to the breeding background of the animals. Only data obtained from animals of similar origin have to be compared, to avoid misinterpretation during the evaluation of the experimental results. [source] |