Orthographic analysis of words during fluency training promotes reading of new similar words

Remediation of a serious lack in reading fluency often takes the form of repeated reading exercises. The present study examines whether transfer of training effects to untrained (neighbour) words can be enhanced by training with an orthographic focus as compared with emphasising semantics. The effect of oral versus silent reading during training is studied as well. Two groups of reading-disabled children (mean age=7 years, 11 months) were given repeated reading training with limited exposure duration (350 ms) in which 15 target words were repeated 20 times in exercises focused on either orthography (N=26) or semantics (N=25). The children were required to either read the target words aloud or perform the exercises silently, but this requirement appeared to have no effect on the training results. The results show that untrained neighbour words benefited more from training targets with an orthographic focus than from exercises with a semantic emphasis. © United Kingdom Literacy Association 2006

A habitat suitability model for predicting coral community and reef distributions in the Galapagos

The coral communities and coral reefs of the Galapagos Marine Reserve support tens of thousands of species, including many rare and endemic species. Reef-building corals are sensitive to elevated temperatures, which have been linked to coral bleaching (loss of symbiotic zooxanthellae) and therefore their distribution around the islands has been strongly affected by extreme climatic events over the last 30 years. Following the 1982–3 El Niño-Southern Oscillation event, coral cover was reduced by 95 %, with further mortality in the 1997–8 event. Although there has been significant recovery of the communities in recent years, there is concern that by 2100 the global climate system and sea surface temperatures will warm by between 1.4° and 5.8°C, which could result in 100% mortality of Galapagos corals. This paper reports a temperature and depth bioclimatic envelope (or niche) model of potential coral distribution, developed using an historical analysis of monthly sea surface temperatures, derived from the NOAA AVHRR over the period 1985–2001, and a near-shore bathymetry data set derived from Shuttle Radar Topography Mission digital topographic data integrated with ship-based depth sounding surveys and digitised hydrographic maps. The model was validated against known coral community and coral reef localities. Application of the model can support the identification of potential new areas where conditions for coral growth are favourable and enable predictions of the effects of future climate change

Circulating antigen tests and urine reagent strips for diagnosis of active schistosomiasis in endemic areas

Background: Point-of-care (POC) tests for diagnosing schistosomiasis include tests based on circulating antigen detection and urine reagent strip tests. If they had sufficient diagnostic accuracy they could replace conventional microscopy as they provide a quicker answer and are easier to use. Objectives: To summarise the diagnostic accuracy of: a) urine reagent strip tests in detecting activeSchistosoma haematobium infection, with microscopy as the reference standard; and b) circulating antigen tests for detecting active Schistosoma infection in geographical regions endemic for Schistosoma mansoni or S. haematobium or both, with microscopy as the reference standard. Search methods: We searched the electronic databases MEDLINE, EMBASE, BIOSIS, MEDION, and Health Technology Assessment (HTA) without language restriction up to 30 June 2014. Selection criteria We included studies that used microscopy as the reference standard: for S. haematobium, microscopy of urine prepared by filtration, centrifugation, or sedimentation methods; and for S. mansoni, microscopy of stool by Kato-Katz thick smear. We included studies on participants residing in endemic areas only. Data collection and analysis: Two review authors independently extracted data, assessed quality of the data using QUADAS-2, and performed meta-analysis where appropriate. Using the variability of test thresholds, we used the hierarchical summary receiver operating characteristic (HSROC) model for all eligible tests (except the circulating cathodic antigen (CCA) POC for S. mansoni, where the bivariate random-effects model was more appropriate). We investigated heterogeneity, and carried out indirect comparisons where data were sufficient. Results for sensitivity and specificity are presented as percentages with 95% confidence intervals (CI). Main results; We included 90 studies; 88 from field settings in Africa. The median S. haematobiuminfection prevalence was 41% (range 1% to 89%) and 36% for S. mansoni (range 8% to 95%). Study design and conduct were poorly reported against current standards. Tests for S. haematobium Urine reagent test strips versus microscopy Compared to microscopy, the detection of microhaematuria on test strips had the highest sensitivity and specificity (sensitivity 75%, 95% CI 71% to 79%; specificity 87%, 95% CI 84% to 90%; 74 studies, 102,447 participants). For proteinuria, sensitivity was 61% and specificity was 82% (82,113 participants); and for leukocyturia, sensitivity was 58% and specificity 61% (1532 participants). However, the difference in overall test accuracy between the urine reagent strips for microhaematuria and proteinuria was not found to be different when we compared separate populations (P = 0.25), or when direct comparisons within the same individuals were performed (paired studies; P = 0.21). When tests were evaluated against the higher quality reference standard (when multiple samples were analysed), sensitivity was marginally lower for microhaematuria (71% vs 75%) and for proteinuria (49% vs 61%). The specificity of these tests was comparable. Antigen assay Compared to microscopy, the CCA test showed considerable heterogeneity; meta-analytic sensitivity estimate was 39%, 95% CI 6% to 73%; specificity 78%, 95% CI 55% to 100% (four studies, 901 participants). Tests for S. mansoni Compared to microscopy, the CCA test meta-analytic estimates for detecting S. mansoni at a single threshold of trace positive were: sensitivity 89% (95% CI 86% to 92%); and specificity 55% (95% CI 46% to 65%; 15 studies, 6091 participants) Against a higher quality reference standard, the sensitivity results were comparable (89% vs 88%) but specificity was higher (66% vs 55%). For the CAA test, sensitivity ranged from 47% to 94%, and specificity from 8% to 100% (four studies, 1583 participants). Authors' conclusions: Among the evaluated tests for S. haematobium infection, microhaematuria correctly detected the largest proportions of infections and non-infections identified by microscopy. The CCA POC test for S. mansoni detects a very large proportion of infections identified by microscopy, but it misclassifies a large proportion of microscopy negatives as positives in endemic areas with a moderate to high prevalence of infection, possibly because the test is potentially more sensitive than microscopy

The development of QUADAS : a tool for the quality assessment of studies of diagnostic accuracy included in systematic reviews

BACKGROUND: In the era of evidence based medicine, with systematic reviews as its cornerstone, adequate quality assessment tools should be available. There is currently a lack of a systematically developed and evaluated tool for the assessment of diagnostic accuracy studies. The aim of this project was to combine empirical evidence and expert opinion in a formal consensus method to develop a tool to be used in systematic reviews to assess the quality of primary studies of diagnostic accuracy. METHODS: We conducted a Delphi procedure to develop the quality assessment tool by refining an initial list of items. Members of the Delphi panel were experts in the area of diagnostic research. The results of three previously conducted reviews of the diagnostic literature were used to generate a list of potential items for inclusion in the tool and to provide an evidence base upon which to develop the tool. RESULTS: A total of nine experts in the field of diagnostics took part in the Delphi procedure. The Delphi procedure consisted of four rounds, after which agreement was reached on the items to be included in the tool which we have called QUADAS. The initial list of 28 items was reduced to fourteen items in the final tool. Items included covered patient spectrum, reference standard, disease progression bias, verification bias, review bias, clinical review bias, incorporation bias, test execution, study withdrawals, and indeterminate results. The QUADAS tool is presented together with guidelines for scoring each of the items included in the tool. CONCLUSIONS: This project has produced an evidence based quality assessment tool to be used in systematic reviews of diagnostic accuracy studies. Further work to determine the usability and validity of the tool continue