Summary
Due to the lack of diagnostics in primary health care, over 75 % of osteoporotic patients are not diagnosed. A new ultrasound method for primary health care is proposed. Results suggest ...applicability of ultrasound method for osteoporosis diagnostics at primary health care.
Introduction
We lack effective screening and diagnostics of osteoporosis at primary health care. In this study, a new ultrasound (US) method is proposed for osteoporosis diagnostics.
Methods
A total of 572 Caucasian women (age 20 to 91 years) were examined using pulse-echo US measurements in the tibia and radius. This method provides an estimate of bone mineral density (BMD), i.e. density index (DI). Areal BMD measurements at the femoral neck (BMD
neck
) and total hip (BMD
total
) were determined by using axial dual-energy X-ray absorptiometry (DXA) for women older than 50 years of age (
n
= 445, age = 68.8 ± 8.5 years). The osteoporosis thresholds for the DI were determined according to the International Society for Clinical Densitometry (ISCD). Finally, the FRAX questionnaire was completed by 425 participants.
Results
Osteoporosis was diagnosed in individuals with a T-score −2.5 or less in the total hip or femoral neck (
n
= 75). By using the ISCD approach for the DI, only 28.7 % of the subjects were found to require an additional DXA measurement. Our results suggest that combination of US measurement and FRAX in osteoporosis management pathways would decrease the number of DXA measurements to 16 % and the same treatment decisions would be reached at 85.4 % sensitivity and 78.5 % specificity levels.
Conclusions
The present results demonstrate a significant correlation between the ultrasound and DXA measurements at the proximal femur. The thresholds presented here with the application to current osteoporosis management pathways show promise for the technique to significantly decrease the amount of DXA referrals and increase diagnostic coverage; however, these results need to be confirmed in future studies.
Accurate, rapid, and multiplexed nucleic acid detection is of great value for applications in biomedicine and agriculture. Here, we demonstrated a one‐step Clustered Regularly Interspaced Short ...Palindromic Repeats (CRISPR) diagnostic method for the digital and multiplexed detection of both single‐stranded (ss) and double‐stranded (ds) DNA on a handheld smartphone device. ssDNA targets exhibited faster reaction kinetics of this single‐step CRISPR–Cas12a assay than dsDNA counterparts. Under optimized conditions, picomolar levels of ssDNA targets can be detected in 96‐well plates by using a benchtop plate reader. The detection sensitivity can be further improved to 5 fM when running the reaction in a microwell‐based digital assay chip. Multiplexed detection of hepatitis B virus and human papillomavirus DNA markers was demonstrated on the smartphone‐based platform. Finally, the one‐step CRISPR–Cas12a assay performed robustly in human serum samples with a recovery rate of ssDNA detection between 96% and 105.6%, suggesting a high potential for clinical diagnostic applications in point‐of‐care settings.
The increased incidence and the significant health burden associated with carcinoma of the prostate have led to substantial changes in its diagnosis over the past century. Despite technological ...advancements, the management of prostate cancer has become progressively more complex and controversial for both early and late-stage disease. The limitations and potential harms associated with the use of prostate-specific antigen (PSA) as a diagnostic marker have stimulated significant investigation of numerous novel biomarkers that demonstrate varying capacities to detect prostate cancer and can decrease unnecessary biopsies. However, only a few of these markers have been approved for specific clinical settings while the others have not been adequately validated for use. This review systematically and critically assesses ongoing issues and emerging challenges in the current state of prostate cancer diagnostic tools and the need for disruptive next generation tools based on analysis of combinations of these biomarkers to enhance predictive accuracy which will benefit clinical diagnostics and patient welfare.
X‐ray free‐electron lasers (XFELs) deliver pulses of coherent X‐rays on the femtosecond time scale, with potentially high repetition rates. While XFELs provide high peak intensities, both the ...intensity and the centroid of the beam fluctuate strongly on a pulse‐to‐pulse basis, motivating high‐rate beam diagnostics that operate over a large dynamic range. The fast drift velocity, low X‐ray absorption and high radiation tolerance properties of chemical vapour deposition diamonds make these crystals a promising candidate material for developing a fast (multi‐GHz) pass‐through diagnostic for the next generation of XFELs. A new approach to the design of a diamond sensor signal path is presented, along with associated characterization studies performed in the XPP endstation of the LINAC Coherent Light Source (LCLS) at SLAC. Qualitative charge collection profiles (collected charge versus time) are presented and compared with those from a commercially available detector. Quantitative results on the charge collection efficiency and signal collection times are presented over a range of approximately four orders of magnitude in the generated electron–hole plasma density.
Two approaches to the design of a diamond sensor signal path were explored using high‐intensity X‐ray pulses from the LINAC Coherent Light Source at SLAC. Results on the charge‐collection efficiency and signal collection time are presented over a range of approximately four orders of magnitude in the generated electron–hole plasma density.
The Clinician-Administered PTSD Scale (CAPS) is an extensively validated and widely used structured diagnostic interview for posttraumatic stress disorder (PTSD). The CAPS was recently revised to ...correspond with PTSD criteria in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; American Psychiatric Association, 2013). This article describes the development of the CAPS for DSM-5 (CAPS-5) and presents the results of an initial psychometric evaluation of CAPS-5 scores in 2 samples of military veterans (Ns = 165 and 207). CAPS-5 diagnosis demonstrated strong interrater reliability (к = .78 to 1.00, depending on the scoring rule) and test-retest reliability (к = .83), as well as strong correspondence with a diagnosis based on the CAPS for DSM-IV (CAPS-IV; к = .84 when optimally calibrated). CAPS-5 total severity score demonstrated high internal consistency (α = .88) and interrater reliability (ICC = .91) and good test-retest reliability (ICC = .78). It also demonstrated good convergent validity with total severity score on the CAPS-IV (r = .83) and PTSD Checklist for DSM-5 (r = .66) and good discriminant validity with measures of anxiety, depression, somatization, functional impairment, psychopathy, and alcohol abuse (rs = .02 to .54). Overall, these results indicate that the CAPS-5 is a psychometrically sound measure of DSM-5 PTSD diagnosis and symptom severity. Importantly, the CAPS-5 strongly corresponds with the CAPS-IV, which suggests that backward compatibility with the CAPS-IV was maintained and that the CAPS-5 provides continuity in evidence-based assessment of PTSD in the transition from DSM-IV to DSM-5 criteria.
Public Significance Statement
This study evaluated the DSM-5 version of the Clinician-Administered PTSD Scale (CAPS-5), a widely used structured interview for posttraumatic stress disorder, in 2 samples of military veterans. Results indicated that the CAPS-5 is psychometrically sound and corresponds closely with the previous DSM-IV version of the CAPS.
Background
Accurate diagnosis of tuberculosis in people living with HIV is difficult. HIV‐positive individuals have higher rates of extrapulmonary tuberculosis and the diagnosis of tuberculosis is ...often limited to imaging results. Ultrasound is such an imaging test that is widely used as a diagnostic tool (including point‐of‐care) in people suspected of having abdominal tuberculosis or disseminated tuberculosis with abdominal involvement.
Objectives
To determine the diagnostic accuracy of abdominal ultrasound for detecting abdominal tuberculosis or disseminated tuberculosis with abdominal involvement in HIV‐positive individuals.
To investigate potential sources of heterogeneity in test accuracy, including clinical setting, ultrasound training level, and type of reference standard.
Search methods
We searched for publications in any language up to 4 April 2019 in the following databases: MEDLINE, Embase, BIOSIS, Science Citation Index Expanded (SCI‐EXPANDED), Social Sciences Citation Index (SSCI), Conference Proceedings Citation Index‐ Science (CPCI‐S), and also ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform to identify ongoing trials.
Selection criteria
We included cross‐sectional, cohort, and diagnostic case‐control studies (prospective and retrospective) that compared the result of the index test (abdominal ultrasound) with one of the reference standards. We only included studies that allowed for extraction of numbers of true positives (TPs), true negatives (TNs), false positives (FPs), and false negatives (FNs). Participants were HIV‐positive individuals aged 15 years and older. A higher‐quality reference standard was the bacteriological confirmation of Mycobacterium tuberculosis from any clinical specimen, and a lower‐quality reference standard was a clinical diagnosis of tuberculosis without microbiological confirmation. We excluded genitourinary tuberculosis.
Data collection and analysis
For each study, two review authors independently extracted data using a standardized form. We assessed the quality of studies using a tailored Quality Assessment of Diagnostic Accuracy Studies‐2 (QUADAS‐2) tool. We used the bivariate model to estimate pooled sensitivity and specificity. When studies were few we simplified the bivariate model to separate univariate random‐effects logistic regression models for sensitivity and specificity. We explored the influence of the type of reference standard on the accuracy estimates by conducting separate analyses for each type of reference standard. We assessed the certainty of the evidence using the GRADE approach.
Main results
We included 11 studies. The risks of bias and concern about applicability were often high or unclear in all domains. We included six studies in the main analyses of any abnormal finding on abdominal ultrasound; five studies reported only individual lesions.
The six studies of any abnormal finding were cross‐sectional or cohort studies. Five of these (83%) were conducted in low‐ or middle‐income countries, and one in a high‐income country. The proportion of participants on antiretroviral therapy was none (1 study), fewer then 50% (4 studies), more than 50% (1 study), and not reported (5 studies). The first main analysis, studies using a higher‐quality reference standard (bacteriological confirmation), had a pooled sensitivity of 63% (95% confidence interval (CI) 43% to 79%; 5 studies, 368 participants; very low‐certainty evidence) and a pooled specificity of 68% (95% CI 42% to 87%; 5 studies, 511 participants; very low‐certainty evidence). If the results were to be applied to a hypothetical cohort of 1000 people with HIV where 200 (20%) have tuberculosis then:
‐ About 382 individuals would have an ultrasound result indicating tuberculosis; of these, 256 (67%) would be incorrectly classified as having tuberculosis (false positives).
‐ Of the 618 individuals with a result indicating that tuberculosis is not present, 74 (12%) would be incorrectly classified as not having tuberculosis (false negatives).
In the second main analysis involving studies using a lower‐quality reference standard (clinical diagnosis), the pooled sensitivity was 68% (95% CI 45% to 85%; 4 studies, 195 participants; very low‐certainty evidence) and the pooled specificity was 73% (95% CI 41% to 91%; 4 studies, 202 participants; very low‐certainty evidence).
Authors' conclusions
In HIV‐positive individuals thought to have abdominal tuberculosis or disseminated tuberculosis with abdominal involvement, abdominal ultrasound appears to have 63% sensitivity and 68% specificity when tuberculosis was bacteriologically confirmed. These estimates are based on data that is limited, varied, and low‐certainty.
The low sensitivity of abdominal ultrasound means clinicians should not use a negative test result to rule out the disease, but rather consider the result in combination with other diagnostic strategies (including clinical signs, chest x‐ray, lateral flow urine lipoarabinomannan assay (LF‐LAM), and Xpert MTB/RIF). Research incorporating the test into tuberculosis diagnostic algorithms will help in delineating more precisely its value in diagnosing abdominal tuberculosis or disseminated tuberculosis with abdominal involvement.
26 September 2019
Up to date
All studies incorporated from most recent search
All studies identified during the most recent search (4 Apr, 2019) have been incorporated in the review, and one ongoing study identified
In the 1960s, thanks to the development of prenatal diagnosis, medicine found a new object of study: the living fetus. At first, prenatal testing was proposed only to women at a high risk of giving ...birth to an impaired child. But in the following decades, such testing has become routine. In Imperfect Pregnancies , Ilana Löwy argues that the generalization of prenatal diagnosis has radically changed the experience of pregnancy for tens of millions of women worldwide. Although most women are reassured that their future child is developing well, others face a stressful period of waiting for results, uncertain prognosis, and difficult decisions. Löwy follows the rise of biomedical technologies that made prenatal diagnosis possible and investigates the institutional, sociocultural, economic, legal, and political consequences of their widespread diffusion. Because prenatal diagnosis is linked to the contentious issue of selective termination of pregnancy for a fetal anomaly, debates on this topic have largely centered on the rejection of human imperfection and the notion that we are now perched on a slippery slope that will lead to new eugenics. Imperfect Pregnancies tells a more complicated story, emphasizing that there is no single standardized way to scrutinize the fetus, but there are a great number of historically conditioned and situated approaches. This book will interest students, scholars, health professionals, administrators, and activists interested in issues surrounding new medical technologies, screening, risk management, pregnancy, disability, and the history and social politics of women’s bodies.
Asymptomatic carriers of Plasmodium parasites hamper malaria control and eradication. Achieving malaria eradication requires ultrasensitive diagnostics for low parasite density infections (<100 ...parasites per microliter blood) that work in resource-limited settings (RLS). Sensitive point-of-care diagnostics are also lacking for nonfalciparum malaria, which is characterized by lower density infections and may require additional therapy for radical cure. Molecular methods, such as PCR, have high sensitivity and specificity, but remain high-complexity technologies impractical for RLS. Here we describe a CRISPR-based diagnostic for ultrasensitive detection and differentiation of Plasmodium falciparum, Plasmodium vivax, Plasmodium ovale, and Plasmodium malariae, using the nucleic acid detection platform SHERLOCK (specific high-sensitivity enzymatic reporter unlocking). We present a streamlined, field-applicable, diagnostic comprised of a 10-min SHERLOCK parasite rapid extraction protocol, followed by SHERLOCK for 60 min for Plasmodium species-specific detection via fluorescent or lateral flow strip readout. We optimized one-pot, lyophilized, isothermal assays with a simplified sample preparation method independent of nucleic acid extraction, and showed that these assays are capable of detection below two parasites per microliter blood, a limit of detection suggested by the World Health Organization. Our P. falciparum and P. vivax assays exhibited 100% sensitivity and specificity on clinical samples (5 P. falciparum and 10 P. vivax samples). This work establishes a field-applicable diagnostic for ultrasensitive detection of asymptomatic carriers as well as a rapid point-of-care clinical diagnostic for nonfalciparum malaria species and low parasite density P. falciparum infections.
Vibration-based rolling element bearing diagnostics is a very well-developed field, yet researchers continue to develop new diagnostic algorithms quite frequently. Over the last decade, data from the ...Case Western Reserve University (CWRU) Bearing Data Center has become a standard reference used to test these algorithms, yet without any recognised benchmark it is difficult to properly assess the performance of any proposed diagnostic methods. There is, then, a clear need to examine the data thoroughly and to categorise it appropriately, and this paper intends to fulfil that objective. To do so, three established diagnostic techniques are applied to the entire CWRU data set, and the diagnostic outcomes are provided and discussed in detail. Recommendations are given as to how the data might best be used, and also on how any future benchmark data should be generated. Though intended primarily as a benchmark to aid in testing new diagnostic algorithms, it is also hoped that much of the discussion will have broader applicability to other bearing diagnostics cases.
•We provide a thorough benchmark analysis of the CWRU Bearing Data.•Three established diagnostic techniques are applied.•We provide the diagnostic outcomes for all data sets as a benchmark reference.•We discuss the records at length and identify data problems and anomalies.•We give recommendations as to how best to use the data for algorithm development.
How to: evaluate a diagnostic test Leeflang, M.M.G.; Allerberger, F.
Clinical microbiology and infection,
January 2019, 2019-Jan, 2019-01-00, 20190101, Letnik:
25, Številka:
1
Journal Article
Recenzirano
Odprti dostop
The development of an in vitro diagnostic test from a good idea to a clinically relevant tool takes several steps, with more stringent requirements at every step.
This article aims to summarize the ...necessary questions to be asked about a test and to illustrate study designs answering these questions. We also aim to relate Regulation (EU) 2017/746 to the needs of evidence-based diagnostic testing, where applicable.
We used literature on evidence-based diagnostics, a text book on clinical trials in the development and marketing of medical devices and the English version of Regulation 2017/746 of the European Parliament and of the Council on in vitro diagnostic medical devices.
The combination of different test uses and different stages of development determine the required test characteristics and suitability of study designs. In an earlier stage of test development it may be crucial to know whether a test can differentiate diseased persons from healthy controls, although this tells us little about how a test will perform in practice. Later stages focus on the diagnostic accuracy of a test in a clinically relevant situation. However, a test that perfectly distinguishes between patients with and without a certain condition may still have little effect on patient outcomes. Therefore, randomized controlled trials of testing may be needed, as well as post-marketing monitoring.
Both researchers and users of tests need to be aware of the limitations of diagnostic test accuracy and realize that accuracy is only indirectly linked to people's health status.
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