Systematic Overview (systematic + overview)

Distribution by Scientific Domains


Selected Abstracts


The causes, consequences and detection of publication bias in psychiatry

ACTA PSYCHIATRICA SCANDINAVICA, Issue 4 2000
Simon M. Gilbody
Objective: Publication bias threatens the validity of published research, although this topic has received little attention in psychiatry. The purpose of this article is to produce a systematic overview of the causes and consequences of publication bias and to summarize the available methods with which it is detected and corrected. Method: Empirical evidence for the existence of publication bias is reviewed and the following methods are applied to an illustrative case example from psychiatry: funnel plot analysis; the ,file drawer method'; linear regression techniques; rank correlation; ,trim and fill'. Results: Small studies are particularly susceptible to publication and related bias. All methods to detect publication bias depend upon the availability of a number of individual studies with a range of sample sizes. Unfortunately, large numbers of studies of varying sample size are not always available in many areas of psychiatric research. Conclusion: Where possible researchers should always test for the presence of publication bias. The problem of publication bias will not be solved by anything other than a prospective trials register. [source]


Museum Geography: Exploring Museums, Collections and Museum Practice in the UK

GEOGRAPHY COMPASS (ELECTRONIC), Issue 10 2010
Hilary Geoghegan
In the UK alone there are more than 2500 museums of interest to international and home audiences. Despite their prevalence and a strong museological culture in the UK and beyond, the geographic study of museums is relatively under-developed. To date there has been no systematic overview of this field either in the UK or internationally. This review article is intended as a contribution towards an emerging ,museum geography'. Beginning with an exploration of research on museums, collections and museum practice, the author then considers the recent ,spatial turn' in museum studies and discusses how geographers have variously encountered museums, collections and museum practice to date. The article then reviews the potential for the future study of museums by geographers. In so doing, the author suggests that the study of museums offers some exciting opportunities for geographical research and teaching. [source]


A 6-year follow-up of dosing, coagulation factor levels and bleedings in relation to joint status in the prophylactic treatment of haemophilia

HAEMOPHILIA, Issue 6 2004
J. Ahnström
Summary., The primary aim of this study was to investigate the possible relationship between coagulation factor level and bleeding frequency during prophylactic treatment of haemophilia after stratification of the patients according to joint scores. The secondary aim was to obtain a systematic overview of the doses of coagulation factors prescribed for prophylaxis at the Malmö haemophilia treatment centre during a 6-year period. A retrospective survey of medical records for the years 1997,2002 and pharmacokinetic study results from the 1990s was complemented by collection of blood samples for coagulation factor assay when needed. Information on the dosing and plasma levels of factor VIII or factor IX, joint scores and incidence of bleedings (joint bleeds and ,other bleeds') was compiled. The patients were stratified by age (0,6, 7,12, 13,18, 19,36 and >36 years) and joint score (0, 1,6 and >6). Individual pharmacokinetic parameters of plasma coagulation factor activities (FVIII:C and FIX:C) were estimated. Trough levels during the treatment were calculated, as well as the number of hours per week of treatment during which plasma FVIII:C/FIX:C fell below a 1, 2 or 3% target level. Fifty-one patients with haemophilia A (two moderate, 49 severe) and 13 with haemophilia B (all severe) were included, yielding data for 364 patient-years of treatment. There was a wide range of dosing schedules, the most common ones being three times a week or every other day for FVIII and twice a week or every third day for FIX. The overall relationship between FVIII:C/FIX:C levels and incidence of joint bleeding was very weak, even after stratification of the patients according to joint score. There was no relationship between coagulation factor level and incidence of other bleeds. In this cohort of patients on high-dose prophylactic treatment, dosing was based more on clinical outcome in terms of bleeding frequency than on the aim to maintain a 1% target level of FVIII:C/FIX:C. Some patients did not bleed in spite of a trough level of <1% and others did in spite of trough levels >3%. The practical implication of our findings is that dosing in prophylactic treatment of haemophilia should be individualized. Thus, proposed standard regimens should be implemented only after careful clinical consideration, with a high readiness for re-assessment and individual dose tailoring. [source]


A review of reliable numerical models for three-dimensional linear parabolic problems

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 1 2007
I. Faragó
Abstract The preservation of characteristic qualitative properties of different phenomena is a more and more important requirement in the construction of reliable numerical models. For phenomena that can be mathematically described by linear partial differential equations of parabolic type (such as the heat conduction, the diffusion, the pricing of options, etc.), the most important qualitative properties are: the maximum,minimum principle, the non-negativity preservation and the maximum norm contractivity. In this paper, we analyse the discrete analogues of the above properties for finite difference and finite element models, and we give a systematic overview of conditions that guarantee the required properties a priori. We have chosen the heat conduction process to illustrate the main concepts, but engineers and scientists involved in scientific computing can easily reformulate the results for other problems too. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Mycobacterial infection and atopy in childhood: A systematic review

PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 7 2007
Charles C. Obihara
The epidemiological relation between mycobacterial infection and the prevalence of atopic disease in humans is still unclear. This is in contrast to studies in murine models in which a clear suppression of atopic symptoms was observed after exposure to mycobacteria or mycobacterial products. We therefore wanted to provide a systematic overview of the published literature on the relationship between mycobacterial infection and atopic disease and to evaluate the causal relationship in a meta-analysis. The EMBASE and MEDLINE databases were searched systematically for papers published in the English literature (1966,2005) on the relation between mycobacterial infection and atopic disease. Original observational or interventional studies involving the paediatric population were included. Two authors independently reviewed articles for data on mycobacterial exposure and atopic disease outcome. Any differences were resolved by discussion. Of a total of 1201 hits, 23 studies (19 cross-sectionals, three case,controls and one prospective cohort) met the inclusion criteria. Only a minority of studies (40%) observed an association between mycobacterial infection and the prevalence of atopic disease outcome. In the meta-analysis, only studies containing data on mycobacterial exposure and atopic disease outcome variables were included. Only cross-sectional studies, in which the relation between a positive tuberculin skin test and allergic symptoms was studied, observed statistically significant negative correlation (odds ratio 0.63; 95% confidence interval: 0.51,0.79). The results of this review show that the evidence of the relationship of mycobacterial infection and atopic disease is based on observations of cross-sectional studies. In a meta-analysis, calculations showed a high level of heterogeneity (I2) within studies with similar design making it difficult to pool effects. This may partly be explained by differences in the type and definition of mycobacterial infection and lack of uniformity in the definition of atopy. The results show that only a minority of studies in the literature shows any evidence of inverse relationship between mycobacterial exposure and atopic disease outcome. The fact that the present epidemiological evidence on the relationship between mycobacterial infection and the development of atopic disease is based mainly on cross-sectional observational studies indicates the need for population-based prospective studies to address this issue. This issue needs to be addressed in view of recent suggestions to developing mycobacterial-based vaccines against atopic disease in the future. [source]


The North American cranberry fruit rot fungal community: a systematic overview using morphological and phylogenetic affinities

PLANT PATHOLOGY, Issue 6 2009
J. J. Polashock
Cranberry fruit rot (CFR) is caused by many species of fungi, with the contribution of any given species to the disease complex varying among plantings of Vaccinium macrocarpon within a site, sites within regions, and among regions and years. This study assessed the morphological and molecular variability of five widespread CFR-causing fungi: Phyllosticta vaccinii, Coleophoma empetri, Colletotrichum acutatum, Colletotrichum gloeosporioides and Physalospora vaccinii. Although the majority of isolates had morphological characteristics consistent with published descriptions, some were atypical. For example, non-chromogenic isolates of C. acutatum were recovered from British Columbia and white isolates of Physalospora vaccinii were recovered in addition to the more common dark isolates. On the basis of sequence analysis of the ITS and large subunit rDNA (LSU), it appears that Phyllosticta vaccinii, C. empetri, C. gloeosporioides and C. acutatum are genetically uniform on cranberry in North America. This suggests the possibility that these fungal species were introduced to cultivated cranberries and concomitantly moved with planting material to new locations. In contrast, white isolates of Physalospora had ITS and LSU sequences distinct from those of their dark counterparts, with phylogenetic analyses suggesting that these isolates represent either different species or distinct members of highly divergent populations. Taxonomic placement of all species based on phylogenetic relationships was consistent with morphological placement, with the exception of Physalospora vaccinii. Unlike other Physalospora species, CFR isolates of Physalospora vaccinii were not allied with the Xylariomycetidae; instead, these fungi were members of the Sordariomycetidae. A deeper taxonomic analysis is needed to resolve this inconsistency in familial affiliation. [source]


How far are the left-behind left behind?

POPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 3 2007
A preliminary study in rural China
Abstract While the linkage between migration and development has attracted much academic and policy attention, a key aspect of the linkage, namely those left behind in the community of origin, remains under-researched. As one of the first academic attempts to provide a systematic overview of this group in China, this paper describes the basic problems faced by it, discusses the institutional causes of the problems, and explores long-term and short-term solutions. The paper first establishes the fact that, while it seems that individuals decide who migrates and who stays back, there are fundamental institutional constraints on such decisions. The paper then shows that the three main left-behind groups, namely wives, the elderly and children, encounter various problems, but in general their situation is not much worse than that of those living with all family members. Their problems cannot just be attributed to being left-behind individuals; instead, the fundamental cause is that many rural communities as a whole have been left behind economically and socially. Although migration exacerbates the hardship, preventing migration is certainly not a solution. The paper instead calls for measures to redress the urban,rural divide and to improve the provision of public goods in rural communities. Copyright © 2006 John Wiley & Sons, Ltd. [source]


Incidence of heterotopic bone formation after major hip surgery

ANZ JOURNAL OF SURGERY, Issue 11 2002
Bruce Neal
Background: Heterotopic bone formation is a well-established complication of major hip surgery, but traditional reviews of the published literature may have underestimated its frequency. Methods: A systematic overview of all the relevant studies was performed to determine reliably the incidence of any heterotopic bone formation and the incidence of each Brooker equivalent grade. Separate estimates were made for patients with total hip replacement and patients with acetabular fracture repair. Results: A computer-based search identified 218 studies with data on the incidence of heterotopic bone formation after either hip replacement or acetabular fracture repair. These studies included data from an estimated 59 121 operated hips among patients that received total hip replacement and an estimated 998 hips among patients that underwent acetabular fracture repair. In these studies, the incidence of any heterotopic bone formation was 43% after total hip replacement and 51% after acetabular fracture repair. The incidence of severe heterotopic bone formation was 9% and 19%, respectively. Conclusions: These results suggest that heterotopic bone formation occurs more frequently after total hip replacement than is generally believed. It is possible that heterotopic bone formation is a more important cause of postoperative disability than has previously been recognized and that effective prophylactic regimens might improve outcome in substantial numbers of patients. [source]


Co-ordinated Bargaining: A Process for Our Times?

BRITISH JOURNAL OF INDUSTRIAL RELATIONS, Issue 2 2002
Keith Sisson
This article draws on past as well as present to offer a systematic overview of co-ordinated bargaining, which many commentators see as a likely vehicle for the ,Europeanization' of industrial relations. It argues that co-ordinated bargaining is indeed likely to play a major role within the EU, reflecting not only trade union pressures but also management's use of benchmarking to promote organizational change and competitiveness. The pace with which co-ordinated bargaining develops is likely to vary considerably both within and between sectors, however, leading to multi-speed ,Europeanization' and further decentralization of collective bargaining within national systems. [source]


Utilization of catheterization and revascularization procedures in patients with non-ST segment elevation acute coronary syndrome over the last decade

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2005
Glenn N. Levine MD
Abstract The degree to which catheterization and revascularization procedures are utilized in patients with non-ST segment elevation acute coronary syndrome (NSTE-ACS) during hospitalization has broad implications with respect to initial pharmacotherapeutic decisions (upfront therapies), treatment and hospital transfer protocols, guideline recommendations, and allocation of training, material, and financial resources. Analysis of data from multiple trials and registries of patients with NSTE-ACS has the potential to assess more broadly utilization of invasive and revascularization procedures and provide a wide angle or bird's-eye view of the management of such patients, complementing the data obtained from any one trial or registry. We therefore undertook a systematic overview of all large trials and registries of patients with NSTE-ACS conducted over the last decade that were deemed appropriate to provide information on catheterization and revascularization procedures. Although not unexpectedly the percentage of patients with NSTE-ACS managed with cardiac catheterization, percutaneous coronary intervention (PCI), and coronary artery bypass grafting varies in different clinical trials and registries, general findings and trends were still discernable from these studies. During the initial treatment period, the majority of patients were ultimately treated with medical therapy alone (e.g., without revascularization). The percentage of those NSTE-ACS patients undergoing diagnostic cardiac catheterization who were then managed with PCI increased over the last decade and now stands at approximately 50%. Of NSTE-ACS patients who undergo revascularization, the percentage of those patients who are revascularized via PCI similarly increased, and PCI is currently the revascularization procedure utilized in approximately three-fourths of patients undergoing revascularization. The percentages of patients undergoing invasive and revascularization procedures were consistently higher in the U.S. cohorts of study subjects when compared to non-U.S. cohorts of study subjects. © 2005 Wiley-Liss, Inc. [source]


Production of Inorganic Nanoparticles by Microorganisms

CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 7 2009
N. Krumov
Abstract A promising new dimension in the field of biotechnology is the use of microorganisms for the production of inorganic nanoscale particles. The interest in nanotechnology is provoked by the unique properties of nanostructured materials and their potential fields of application ranging from medicine to electronics. This review article presents a systematic overview of the microorganisms capable of producing nanoparticles, and describes cellular mechanisms and outlines cultivation conditions that turn this process into a successful synthetic pathway. [source]


3333: The clinical spectrum of corneal dystrophies

ACTA OPHTHALMOLOGICA, Issue 2010
P KESTELYN
Purpose To review the most common corneal dystrophies from the clinician's standpoint. Methods A systematic overview of the natural history and the clinical characteristics of the most common corneal dystrophies will be presented following the anatomic classification: epithelial and anterior stromal dystrophies, stromal dystrophies, and Descemet and endothelial dystrophies. Abundant use of slitlamp images will help to illustrate the most salient clinical features. Conclusion Despite the fact that the knowledge about the genetic mutations responsible for the different corneal dystrophies has led to a better understanding of their basic defect and to molecular tests for their precise diagnosis, in most patients the careful examination at the slitlamp combined with personal and family history will remain the cornerstone for diagnosis, counseling and treatment. [source]