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Study Design: Systematic review.Objective: To determine the validity of the Hoffmann sign for the detection of degenerative cervical myelopathy (DCM) for patients presenting with cervical complaints.Summary Of Background Data: While physical examination maneuvers are often used to diagnose DCM, no previous review has synthesized diagnostic accuracy data.Methods: Medline, Embase, and HealthStar were searched for articles from January 1, 1947 to March 1, 2017 using the following terms: Spinal Cord Diseases, Spinal Cord Compression, Cervical Vertebrae, Signs and Symptoms, Physical Examination, Epidemiologic studies, Epidemiologic Research Design, Predictive Value of Tests, and Myelopathy. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist was applied to determine the level of evidence. Articles included were published in English or French language, rated as QUADAS level 3 or higher with a minimum 10 patients presenting with cervical complaints having undergone the Hoffman sign. Excluded studies recruited patients with a nondegenerative type of cervical myelopathy, and/or no evaluation with magnetic resonance imaging.Results: A total of 589 articles were selected for review. Following the application of inclusion and exclusion criteria, 45 articles were analyzed using the QUADAS checklist. Only of three articles were of QUADAS quality 3 or higher. Analysis of combined data from 2/3 studies indicated that the Hoffman sign has a positive likelihood ratio of 2.2 (95% CI 1.5-3.3) and a negative likelihood ratio of 0.63 (95% CI 0.5-0.8).Conclusion: A positive Hoffman alone is unlikely to lead to more than a small change in estimated probability of DCM as compared with the gold standard test (magnetic resonance imaging). Variability in results across individual studies may result from differences in study design. There are insufficient data to support use of the Hoffman sign alone to confirm or refute a diagnosis of DCM.Level Of Evidence: 1. [ABSTRACT FROM AUTHOR]

Objectives With rapidly increasing numbers of publications, assessments of study quality, reporting quality, and classification of studies according to their level of evidence or developmental stage have become key issues in weighing the relevance of new information reported. Diagnostic marker studies are often criticized for yielding highly discrepant and even controversial results. Much of this discrepancy has been attributed to differences in study quality. So far, numerous tools for measuring study quality have been developed, but few of them have been used for systematic reviews and meta-analysis. This is owing to the fact that most tools are complicated and time consuming, suffer from poor reproducibility, and do not permit quantitative scoring. Methods The International Bladder Cancer Network (IBCN) has adopted this problem and has systematically identified the more commonly used tools developed since 2000. Results In this review, those tools addressing study quality (Quality Assessment of Studies of Diagnostic Accuracy and Newcastle-Ottawa Scale), reporting quality (Standards for Reporting of Diagnostic Accuracy), and developmental stage (IBCN phases) of studies on diagnostic markers in bladder cancer are introduced and critically analyzed. Based upon this, the IBCN has launched an initiative to assess and validate existing tools with emphasis on diagnostic bladder cancer studies. Conclusions The development of simple and reproducible tools for quality assessment of diagnostic marker studies permitting quantitative scoring is suggested. [ABSTRACT FROM AUTHOR]

Objectives: To provide an overview of reporting and methodological quality in diagnostic test accuracy (DTA) studies in the musculoskeletal field and evaluate the use of the QUality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist. Study Design and Setting: A literature review identified all systematic reviews that evaluated the accuracy of clinical tests to diagnose musculoskeletal conditions and used the QUADAS checklist. Two authors screened all identified reviews and extracted data on the target condition, index tests, reference standard, included studies, and QUADAS items. A descriptive analysis of the QUADAS checklist was performed, along with Rasch analysis to examine the construct validity and internal reliability. Results: A total of 19 systematic reviews were included, which provided data on individual items of the QUADAS checklist for 392 DTA studies. In the musculoskeletal field, uninterpretable or intermediate test results are commonly not reported, with 175 (45%) studies scoring ''no'' to this item. The proportion of studies fulfilling certain items varied from 22% (item 11) to 91% (item 3). The interrater reliability of the QUADAS checklist was good and Rasch analysis showed excellent construct validity and internal consistency. Conclusion: This overview identified areas where the reporting and performance of diagnostic studies within the musculoskeletal field can be improved. [ABSTRACT FROM AUTHOR]

Background Drawing conclusions from systematic reviews of test accuracy studies without considering the methodological quality (risk of bias) of included studies may lead to unwarranted optimism about the value of the test(s) under study. We sought to identify to what extent the results of quality assessment of included studies are incorporated in the conclusions of diagnostic accuracy reviews. Methods We searched MEDLINE and EMBASE for test accuracy reviews published between May and September 2012. We examined the abstracts and main texts of these reviews to see whether and how the results of quality assessment were linked to the accuracy estimates when drawing conclusions. Results We included 65 reviews of which 53 contained a meta-analysis. Sixty articles (92%) had formally assessed the methodological quality of included studies, most often using the original QUADAS tool (n = 44, 68%). Quality assessment was mentioned in 28 abstracts (43%); with a majority (n = 21) mentioning it in the methods section. In only 5 abstracts (8%) were results of quality assessment incorporated in the conclusions. Thirteen reviews (20%) presented results of quality assessment in the main text only, without further discussion. Forty-seven reviews (72%) discussed results of quality assessment; the most frequent form was as limitations in assessing quality (n = 28). Only 6 reviews (9%) further linked the results of quality assessment to their conclusions, 3 of which did not conduct a meta-analysis due to limitations in the quality of included studies. In the reviews with a meta-analysis, 19 (36%) incorporated quality in the analysis. Eight reported significant effects of quality on the pooled estimates; in none of them these effects were factored in the conclusions. Conclusion While almost all recent diagnostic accuracy reviews evaluate the quality of included studies, very few consider results of quality assessment when drawing conclusions. The practice of reporting systematic reviews of test accuracy should improve if readers not only want to be informed about the limitations in the available evidence, but also on the associated implications for the performance of the evaluated tests. [ABSTRACT FROM AUTHOR]

Abstract: Background: Positron emission tomography (PET) imaging using the radiotracer 18F-Fluorothymidine (FLT) has been proposed as an imaging biomarker of tumour proliferation. If FLT-PET can be established as such it will provide a non-invasive, quantitative measurement of tumour proliferation across the entire tumour. Results from validation studies have so far been conflicting with some studies confirming a good correlation between FLT uptake and Ki-67 score and others presenting negative results. Methods: Firstly we performed a systematic review of published studies between 1998 and 2011 that explored the correlation between FLT uptake and Ki-67 score and examined possible variations in the methods used. Studies were eligible if they: (a) included patients with cancer, (b) investigated the correlation between Ki-67 measured by immunohistochemistry and FLT uptake measured with PET scanning, and (c) were published as a full paper in a peer-reviewed scientific journal. Secondly a meta-analysis of the correlation coefficient values reported from each study was performed. Correlation coefficient (r) values were extracted from each study and 95% confidence intervals (CIs) were calculated after applying Fisher’s z transformation. For subgroup analysis, studies were classified by the index used to characterise Ki-67 expression (average or maximum expression), the nature of the sample (whole specimen or biopsy) and the cancer type. Findings: Twenty-seven studies were identified as eligible for the meta-analysis. In the studies we examined there were variations in aspects of the methods and reporting. The meta-analysis showed that given an appropriate study design the FLT/Ki-67 correlation is significant and independent of cancer type. Specifically subgroup analysis showed that FLT/Ki-67 correlation was high in studies measuring the Ki-67 average expression regardless of use of surgery or biopsy samples (r =0.70, 95% CI=0.43–0.86, p <0.001). Of the studies that measured Ki-67 maximum expression, only those that used the whole surgical specimen provided a significant r value (r =0.72, 95% CI=0.54–0.84, p <0.001). Studies that used biopsy samples for Ki-67 maximum measurements did not produce a significant r value (r =0.04, 95% CI=−0.18–0.26, p =0.71). In terms of the cancer type subgroup analysis there is sufficient data to support a strong FLT/Ki-67 correlation for brain, lung and breast cancer. No publication bias was detected. Interpretation: This systematic review and meta-analysis highlights the importance of the methods used in validation studies comparing FLT-PET imaging with the biomarker Ki-67. The correlation is significant and independent of cancer type provided a study design that uses Ki-67 average measurements, regardless of nature of sample, or whole surgical samples when measuring Ki-67 maximum expression. Sufficient data to support a strong correlation for brain, lung and breast cancer exist. However, larger, prospective studies with improved study design are warranted to validate these findings for the rest of the cancer types. [Copyright &y& Elsevier]