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1.
Am J Epidemiol ; 193(3): 548-560, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-37939113

RESUMO

In a recent systematic review, Bastos et al. (Ann Intern Med. 2021;174(4):501-510) compared the sensitivities of saliva sampling and nasopharyngeal swabs in the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by assuming a composite reference standard defined as positive if either test is positive and negative if both tests are negative (double negative). Even under a perfect specificity assumption, this approach ignores the double-negative results and risks overestimating the sensitivities due to residual misclassification. In this article, we first illustrate the impact of double-negative results in the estimation of the sensitivities in a single study, and then propose a 2-step latent class meta-analysis method for reevaluating both sensitivities using the same published data set as that used in Bastos et al. by properly including the observed double-negative results. We also conduct extensive simulation studies to compare the performance of the proposed method with Bastos et al.'s method for varied levels of prevalence and between-study heterogeneity. The results demonstrate that the sensitivities are overestimated noticeably using Bastos et al.'s method, and the proposed method provides a more accurate evaluation with nearly no bias and close-to-nominal coverage probability. In conclusion, double-negative results can significantly impact the estimated sensitivities when a gold standard is absent, and thus they should be properly incorporated.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , SARS-CoV-2 , Resultados Negativos , Saliva , Nasofaringe
2.
Biometrics ; 80(3)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38994641

RESUMO

This article addresses the challenge of estimating receiver operating characteristic (ROC) curves and the areas under these curves (AUC) in the context of an imperfect gold standard, a common issue in diagnostic accuracy studies. We delve into the nonparametric identification and estimation of ROC curves and AUCs when the reference standard for disease status is prone to error. Our approach hinges on the known or estimable accuracy of this imperfect reference standard and the conditional independent assumption, under which we demonstrate the identifiability of ROC curves and propose a nonparametric estimation method. In cases where the accuracy of the imperfect reference standard remains unknown, we establish that while ROC curves are unidentifiable, the sign of the difference between two AUCs is identifiable. This insight leads us to develop a hypothesis-testing method for assessing the relative superiority of AUCs. Compared to the existing methods, the proposed methods are nonparametric so that they do not rely on the parametric model assumptions. In addition, they are applicable to both the ROC/AUC analysis of continuous biomarkers and the AUC analysis of ordinal biomarkers. Our theoretical results and simulation studies validate the proposed methods, which we further illustrate through application in two real-world diagnostic studies.


Assuntos
Área Sob a Curva , Simulação por Computador , Curva ROC , Humanos , Padrões de Referência , Estatísticas não Paramétricas , Biomarcadores/análise , Modelos Estatísticos
3.
Am J Bot ; 111(3): e16300, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38469876

RESUMO

PREMISE: Many plastomes of autotrophic Piperales have been reported to date, describing a variety of differences. Most studies focused only on a few species or a single genus, and extensive, comparative analyses have not been done. Here, we reviewed publicly available plastome reconstructions for autotrophic Piperales, reanalyzed publicly available raw data, and provided new sequence data for all previously missing genera. Comparative plastome genomics of >100 autotrophic Piperales were performed. METHODS: We performed de novo assemblies to reconstruct the plastomes of newly generated sequence data. We used Sanger sequencing and read mapping to verify the assemblies and to bridge assembly gaps. Furthermore, we reconstructed the phylogenetic relationships as a foundation for comparative plastome genomics. RESULTS: We identified a plethora of assembly and annotation issues in published plastome data, which, if unattended, will lead to an artificial increase of diversity. We were able to detect patterns of missing and incorrect feature annotation and determined that the inverted repeat (IR) boundaries were the major source for erroneous assembly. Accounting for the aforementioned issues, we discovered relatively stable junctions of the IRs and the small single-copy region (SSC), whereas the majority of plastome variations among Piperales stems from fluctuations of the boundaries of the IR and the large single-copy (LSC) region. CONCLUSIONS: This study of all available plastomes of autotrophic Piperales, expanded by new data for previously missing genera, highlights the IR-LSC junctions as a potential marker for discrimination of various taxonomic levels. Our data indicates a pseudogene-like status for cemA and ycf15 in various Piperales. Based on a review of published data, we conclude that incorrect IR-SSC boundary identification is the major source for erroneous plastome assembly. We propose a gold standard for assembly and annotation of high-quality plastomes based on de novo assembly methods and appropriate references for gene annotation.


Assuntos
Magnoliopsida , Filogenia , Magnoliopsida/genética , Genômica
4.
Paediatr Perinat Epidemiol ; 38(5): 426-431, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38531639

RESUMO

BACKGROUND: No data exist at the population level on what tests are used to aid in the diagnosis of autism spectrum disorder in community practice. OBJECTIVES: To describe autism spectrum disorder testing practices to inform autism spectrum disorder identification efforts. METHODS: Data are from the Autism and Developmental Disabilities Monitoring Network, a multi-site surveillance system reporting prevalence estimates and characteristics of 8-year-old children with autism spectrum disorder. Percentages of children with autism spectrum disorder who received any autism spectrum disorder test or a 'gold standard' test were calculated by site, sex, race, median household income, and intellectual ability status. Risk ratios were calculated to compare group differences. RESULTS: Of 5058 8-year-old children with autism spectrum disorder across 11 sites, 3236 (64.0%) had a record of any autism spectrum disorder test and 2136 (42.2%) had a 'gold standard' ADOS or ADI-R test. Overall, 115 children (2.3%) had both the ADOS and ADI-R in their records. Differences persisted across race, median household income, and intellectual ability status. Asian/Pacific Islander children had the highest percent receiving any ASD test (71.8%; other groups range: 57.4-66.0%) and White children had the highest percent receiving 'gold standard' tests (46.4%; other groups range: 35.6-43.2%). Children in low-income neighbourhoods had a lower percent of any test (62.5%) and 'gold standard' tests (39.4%) compared to medium (70.2% and 47.5%, respectively) and high (69.6% and 46.8%, respectively) income neighbourhoods. Children with intellectual disability had a lower percent of any ASD test (81.7%) and 'gold standard' tests (52.6%) compared to children without intellectual disability (84.0% and 57.6%, respectively). CONCLUSIONS: Autism spectrum disorder testing practices vary widely by site and differ by race and presence of co-occurring intellectual disability, suggesting opportunities to standardise and/or improve autism spectrum disorder identification practices.


Assuntos
Transtorno do Espectro Autista , Humanos , Masculino , Criança , Feminino , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Estados Unidos/epidemiologia , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/epidemiologia , Prevalência , Vigilância da População/métodos
5.
BMC Infect Dis ; 24(1): 163, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321395

RESUMO

BACKGROUND: Diagnosis of tuberculous meningitis (TBM) is hampered by the lack of a gold standard. Current microbiological tests lack sensitivity and clinical diagnostic approaches are subjective. We therefore built a diagnostic model that can be used before microbiological test results are known. METHODS: We included 659 individuals aged [Formula: see text] years with suspected brain infections from a prospective observational study conducted in Vietnam. We fitted a logistic regression diagnostic model for TBM status, with unknown values estimated via a latent class model on three mycobacterial tests: Ziehl-Neelsen smear, Mycobacterial culture, and GeneXpert. We additionally re-evaluated mycobacterial test performance, estimated individual mycobacillary burden, and quantified the reduction in TBM risk after confirmatory tests were negative. We also fitted a simplified model and developed a scoring table for early screening. All models were compared and validated internally. RESULTS: Participants with HIV, miliary TB, long symptom duration, and high cerebrospinal fluid (CSF) lymphocyte count were more likely to have TBM. HIV and higher CSF protein were associated with higher mycobacillary burden. In the simplified model, HIV infection, clinical symptoms with long duration, and clinical or radiological evidence of extra-neural TB were associated with TBM At the cutpoints based on Youden's Index, the sensitivity and specificity in diagnosing TBM for our full and simplified models were 86.0% and 79.0%, and 88.0% and 75.0% respectively. CONCLUSION: Our diagnostic model shows reliable performance and can be developed as a decision assistant for clinicians to detect patients at high risk of TBM. Diagnosis of tuberculous meningitis is hampered by the lack of gold standard. We developed a diagnostic model using latent class analysis, combining confirmatory test results and risk factors. Models were accurate, well-calibrated, and can support both clinical practice and research.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose Meníngea , Humanos , Idoso , Tuberculose Meníngea/diagnóstico , Análise de Classes Latentes , Teorema de Bayes , Sensibilidade e Especificidade , Convulsões
6.
Paediatr Anaesth ; 34(4): 318-323, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38055618

RESUMO

BACKGROUND/AIMS: Traditional manual methods of extracting anesthetic and physiological data from the electronic health record rely upon visual transcription by a human analyst that can be labor-intensive and prone to error. Technical complexity, relative inexperience in computer coding, and decreased access to data warehouses can deter investigators from obtaining valuable electronic health record data for research studies, especially in under-resourced settings. We therefore aimed to develop, pilot, and demonstrate the effectiveness and utility of a pragmatic data extraction methodology. METHODS: Expired sevoflurane concentration data from the electronic health record transcribed by eye was compared to an intermediate preprocessing method in which the entire anesthetic flowsheet narrative report was selected, copy-pasted, and processed using only Microsoft Word and Excel software to generate a comma-delimited (.csv) file. A step-by-step presentation of this method is presented. Concordance rates, Pearson correlation coefficients, and scatterplots with lines of best fit were used to compare the two methods of data extraction. RESULTS: A total of 1132 datapoints across eight subjects were analyzed, accounting for 18.9 h of anesthesia time. There was a high concordance rate of data extracted using the two methods (median concordance rate 100% range [96%, 100%]). The median time required to complete manual data extraction was significantly longer compared to the time required using the intermediate method (240 IQR [199, 482.5] seconds vs 92.5 IQR [69, 99] seconds, p = .01) and was linearly associated with the number of datapoints (rmanual = .97, p < .0001), whereas time required to complete data extraction using the intermediate approach was independent of the number of datapoints (rintermediate = -.02, p = .99). CONCLUSIONS: We describe a pragmatic data extraction methodology that does not require additional software or coding skills intended to enhance the ease, speed, and accuracy of data collection that could assist in clinician investigator-initiated research and quality/process improvement projects.


Assuntos
Anestésicos , Registros Eletrônicos de Saúde , Humanos , Anestésicos/farmacologia
7.
Int J Neurosci ; : 1-7, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38963350

RESUMO

OBJECTIVE: To analyze the diagnostic value of HR-VWI in intracranial arterial stenosis and occlusion and compare it with DSA. METHODS: A retrospective analysis of clinical data of 59 patients with intracranial arterial stenosis in our hospital was conducted to compare the diagnostic results of the two methods for different degrees of intracranial stenosis and various morphological plaques. RESULTS: The diagnosis of stenosis and occlusion by both methods showed no significant difference (p > 0.05). Comparison of plaque morphology detected by HR-VWI with pathological examination results showed no significant difference (p > 0.05); however, there was a significant difference between plaque morphology detected by DSA and pathological examination results (p < 0.05). Additionally, there was a significant difference between plaque morphology detected by HR-VWI and DSA (p < 0.05). CONCLUSION: HR-VWI technique is comparable to DSA technique in diagnosing intracranial arterial stenosis and occlusion, but it is superior to DSA in plaque morphology diagnosis.

8.
Z Psychosom Med Psychother ; 70(2): 106-111, 2024 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-39012191

RESUMO

Recently Papola et al. (2023) published a network meta-analysis (NMA) on psychotherapy of generalized anxiety disorder (GAD) and concluded that cognitive-behavioral therapy (CBT) should be considered the first-line treatment for GAD. However, there are several concerns with regard to the procedures and the conclusions of this NMA and of NMA in general. We show that these concerns question the conclusions by Papola et al. Furthermore, we place concerns about thisNMAin a broader context and question whether existing evidence is consistent with the notion that one form of psychotherapy can be regarded as the gold standard for mental disorders and for all patients and therapists.


Assuntos
Transtornos de Ansiedade , Terapia Cognitivo-Comportamental , Humanos , Transtornos de Ansiedade/terapia , Transtornos de Ansiedade/psicologia , Transtornos de Ansiedade/diagnóstico , Psicoterapia , Metanálise como Assunto
9.
BMC Bioinformatics ; 23(Suppl 9): 570, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918777

RESUMO

BACKGROUND: Automatic literature based discovery attempts to uncover new knowledge by connecting existing facts: information extracted from existing publications in the form of [Formula: see text] and [Formula: see text] relations can be simply connected to deduce [Formula: see text]. However, using this approach, the quantity of proposed connections is often too vast to be useful. It can be reduced by using subject[Formula: see text](predicate)[Formula: see text]object triples as the [Formula: see text] relations, but too many proposed connections remain for manual verification. RESULTS: Based on the hypothesis that only a small number of subject-predicate-object triples extracted from a publication represent the paper's novel contribution(s), we explore using BERT embeddings to identify these before literature based discovery is performed utilizing only these, important, triples. While the method exploits the availability of full texts of publications in the CORD-19 dataset-making use of the fact that a novel contribution is likely to be mentioned in both an abstract and the body of a paper-to build a training set, the resulting tool can be applied to papers with only abstracts available. Candidate hidden knowledge pairs generated from unfiltered triples and those built from important triples only are compared using a variety of timeslicing gold standards. CONCLUSIONS: The quantity of proposed knowledge pairs is reduced by a factor of [Formula: see text], and we show that when the gold standard is designed to avoid rewarding background knowledge, the precision obtained increases up to a factor of 10. We argue that the gold standard needs to be carefully considered, and release as yet undiscovered candidate knowledge pairs based on important triples alongside this work.


Assuntos
Descoberta do Conhecimento , Conhecimento
10.
Stat Med ; 42(4): 536-558, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36577519

RESUMO

If design parameters are chosen appropriately, group sequential trial designs are known to be able to reduce the expected sample size under the alternative hypothesis compared to single-stage designs. The same holds true for the so-called 'gold-standard' design for non-inferiority trials, a design involving an experimental group, an active control group, and a placebo group. However, choosing design parameters that maximize the advantages of a two-stage approach for the three-arm gold-standard design for non-inferiority trials is not a straightforward task. In particular, optimal choices of futility boundaries for this design have not been thoroughly discussed in existing literature. We present a variation of the hierarchical testing procedure, which allows for the incorporation of binding futility boundaries at interim analyses. We show that this procedure maintains strong control of the family-wise type I error rate. Within this framework, we consider the futility and efficacy boundaries as well as the sample size allocation ratios as optimization parameters. This allows the investigation of the efficiency gain from including the option to stop for futility in addition to the ability to stop for efficacy. To analyze the extended designs, optimality criteria that include the design's performance under the alternative as well as the null hypothesis are introduced. On top of this, we discuss methods to limit the allocation of placebo patients in the trial while maintaining relatively good operating characteristics. The results of our numerical optimization procedure are discussed and a comparison of different approaches to designing a three-arm gold-standard non-inferiority trial is provided.


Assuntos
Futilidade Médica , Projetos de Pesquisa , Humanos , Tamanho da Amostra , Grupos Controle
11.
BMC Med Res Methodol ; 23(1): 127, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231347

RESUMO

BACKGROUND: The statistical models developed for meta-analysis of diagnostic test accuracy studies require specialised knowledge to implement. This is especially true since recent guidelines, such as those in Version 2 of the Cochrane Handbook of Systematic Reviews of Diagnostic Test Accuracy, advocate more sophisticated methods than previously. This paper describes a web-based application - MetaBayesDTA - that makes many advanced analysis methods in this area more accessible. RESULTS: We created the app using R, the Shiny package and Stan. It allows for a broad array of analyses based on the bivariate model including extensions for subgroup analysis, meta-regression and comparative test accuracy evaluation. It also conducts analyses not assuming a perfect reference standard, including allowing for the use of different reference tests. CONCLUSIONS: Due to its user-friendliness and broad array of features, MetaBayesDTA should appeal to researchers with varying levels of expertise. We anticipate that the application will encourage higher levels of uptake of more advanced methods, which ultimately should improve the quality of test accuracy reviews.


Assuntos
Modelos Estatísticos , Software , Humanos , Sensibilidade e Especificidade , Teorema de Bayes , Revisões Sistemáticas como Assunto
12.
Annu Rev Clin Psychol ; 19: 107-131, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-36475718

RESUMO

The use of repeated, momentary, real-world assessment methods known as the Experience Sampling Method and Ecological Momentary Assessment (EMA) has been broadly embraced over the last few decades. These methods have extended our assessment reach beyond lengthy retrospective self-reports as they can capture everyday experiences in their immediate context, including affect, behavior, symptoms, and cognitions. In this review we evaluate nine conceptual, methodological, and psychometric issues about EMA with the goal of stimulating conversation and guiding future research on these matters: the extent to which participants are actually reporting momentary experiences, respondents' interpretation of momentary questions, the use of comparison standards in responding, efforts to increase the EMA reporting period beyond the moment to longer periods within a day, training of EMA study participants, concerns about selection bias of respondents, the impact of missing EMA assessments, the reliability of momentary data, and for which purposes EMA might be considered a gold standard for assessment. Resolution of these issues should have far-reaching implications for advancing the field.


Assuntos
Avaliação Momentânea Ecológica , Projetos de Pesquisa , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes
13.
Arch Gynecol Obstet ; 308(2): 643-649, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37145134

RESUMO

PURPOSE: Vulvar lichen sclerosus (LS) is a chronic debilitating inflammatory skin disease. Today, the gold standard is a life-long topical steroid treatment. Alternative options are highly desired. We present a study protocol of a prospective, randomized, active-controlled, investigator-initiated clinical trial comparing a novel non-invasive dual Nd:YAG/Er:YAG laser therapy with the gold standard for the management of LS. METHODS: We recruited 66 patients, 44 in the laser arm and 22 in the steroid arm. Patients with a physician-administered clinical LS score ≥ 4 were included. Participants received either four laser treatments 1-2 months apart, or 6 months of topical steroid application. Follow-ups were planned at 6, 12, and 24 months. The primary outcome looks at the efficacy of the laser treatment at the 6-month follow-up. Secondary outcomes look at comparisons between baseline and follow-ups within the laser or the steroid arm, and comparisons between laser vs. steroid arm. Objective (LS score, histopathology, photo documentation) and subjective (Vulvovaginal Symptoms Questionnaire, symptom VAS score, patient satisfaction) measurements, tolerability, and adverse events are evaluated. CONCLUSION: The findings of this trial have the potential to offer a novel treatment option for LS. The standardized Nd:YAG/Er:YAG laser settings and the treatment regime are presented in this paper. CLINICAL TRIAL IDENTIFICATION NUMBER: NCT03926299.


Assuntos
Lasers de Estado Sólido , Líquen Escleroso Vulvar , Feminino , Humanos , Líquen Escleroso Vulvar/tratamento farmacológico , Líquen Escleroso Vulvar/etiologia , Lasers de Estado Sólido/uso terapêutico , Estudos Prospectivos , Satisfação do Paciente , Esteroides , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Mult Scler ; 28(11): 1762-1772, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35531593

RESUMO

BACKGROUND: Routine cognitive screening is a priority in MS clinical care. The National Institutes of Health Toolbox (NIHTB) Cognition Battery is a 30-min instrument validated in neurological populations excluding MS. OBJECTIVES: To assess construct validity of NIHTB tests and compare classification of cognitive impairment with gold-standard tests. To evaluate relationships between fluid cognition and clinical measures. METHODS: Eighty-seven individuals, aged 30-59 years, completed the NIHTB, Minimal Assessment of Cognitive Function in MS (MACFIMS), Wechsler Adult Intelligence Scale-IV subtests, and measures of disease severity, depression, and fatigue. RESULTS: The NIHTB showed adequate convergent validity for processing speed, working memory, and episodic memory. Although fluid cognition scores from the NIHTB and MACFIMS classified a similar proportion of participants as cognitively impaired, the two batteries differed in which individuals were classified as impaired versus preserved. NIHTB fluid cognition was inversely correlated with disease severity but not related to depression or fatigue. CONCLUSIONS: The NIHTB concords with gold-standard measures, and classifies cognitive impairment at similar rates to the MACFIMS. Adjusted NIHTB fluid cognition was negatively associated with disease severity suggesting clinical utility. Psychometric validation of the NIHTB in clinical practice will elucidate its promise as a cognitive screener in MS.


Assuntos
Esclerose Múltipla , Adulto , Cognição , Fadiga/diagnóstico , Fadiga/etiologia , Humanos , Esclerose Múltipla/complicações , Esclerose Múltipla/diagnóstico , Testes Neuropsicológicos , Reprodutibilidade dos Testes
15.
Stat Med ; 41(3): 433-448, 2022 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-34859902

RESUMO

Diagnostic accuracy, a measure of diagnostic tests for correctly identifying patients with or without a target disease, plays an important role in evidence-based medicine. Diagnostic accuracy of a new test ideally should be evaluated by comparing to a gold standard; however, in many medical applications it may be invasive, costly, or even unethical to obtain a gold standard for particular diseases. When the accuracy of a new candidate test under evaluation is assessed by comparison to an imperfect reference test, bias is expected to occur and result in either overestimates or underestimates of its true accuracy. In addition, diagnostic test studies often involve repeated measurements of the same patient, such as the paired eyes or multiple teeth, and generally lead to correlated and clustered data. Using the conventional statistical methods to estimate diagnostic accuracy can be biased by ignoring the within-cluster correlations. Despite numerous statistical approaches have been proposed to tackle this problem, the methodology to deal with correlated and clustered data in the absence of a gold standard is limited. In this article, we propose a method based on the composite likelihood function to derive simple and intuitive closed-form solutions for estimates of diagnostic accuracy, in terms of sensitivity and specificity. Through simulation studies, we illustrate the relative advantages of the proposed method over the existing methods that simply treat an imperfect reference test as a gold standard in correlated and clustered data. Compared with the existing methods, the proposed method can reduce not only substantial bias, but also the computational burden. Moreover, to demonstrate the utility of this approach, we apply the proposed method to the study of National-Eye-Institute-funded Telemedicine Approaches to Evaluating of Acute-Phase Retinopathy of Prematurity (e-ROP), for estimating accuracies of both the ophthalmologist examination and the image evaluation.


Assuntos
Oftalmopatias , Recém-Nascido Prematuro , Viés , Humanos , Recém-Nascido , Funções Verossimilhança , Sensibilidade e Especificidade
16.
Stat Med ; 41(25): 5033-5045, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-35979723

RESUMO

For indications where only unstable reference treatments are available and use of placebo is ethically justified, three-arm "gold standard" designs with an experimental, reference and placebo arm are recommended for non-inferiority trials. In such designs, the demonstration of efficacy of the reference or experimental treatment is a requirement. They have the disadvantage that only little can be concluded from the trial if the reference fails to be efficacious. To overcome this, we investigate novel single-stage, adaptive test strategies where non-inferiority is tested only if the reference shows sufficient efficacy and otherwise δ $$ \delta $$ -superiority of the experimental treatment over placebo is tested. With a properly chosen superiority margin, δ $$ \delta $$ -superiority indirectly shows non-inferiority. We optimize the sample size for several decision rules and find that the natural, data driven test strategy, which tests non-inferiority if the reference's efficacy test is significant, leads to the smallest overall and placebo sample sizes. We proof that under specific constraints on the sample sizes, this procedure controls the family-wise error rate. All optimal sample sizes are found to meet this constraint. We finally show how to account for a relevant placebo drop-out rate in an efficient way and apply the new test strategy to a real life data set.


Assuntos
Projetos de Pesquisa , Humanos , Tamanho da Amostra
17.
J Biomed Inform ; 125: 103961, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34879250

RESUMO

Rare diseases affect a small number of people compared to the general population. However, more than 6,000 different rare diseases exist and, in total, they affect more than 300 million people worldwide. Rare diseases share as part of their main problem, the delay in diagnosis and the sparse information available for researchers, clinicians, and patients. Finding a diagnostic can be a very long and frustrating experience for patients and their families. The average diagnostic delay is between 6-8 years. Many of these diseases result in different manifestations among patients, which hampers even more their detection and the correct treatment choice. Therefore, there is an urgent need to increase the scientific and medical knowledge about rare diseases. Natural Language Processing (NLP) can help to extract relevant information about rare diseases to facilitate their diagnosis and treatments, but most NLP techniques require manually annotated corpora. Therefore, our goal is to create a gold standard corpus annotated with rare diseases and their clinical manifestations. It could be used to train and test NLP approaches and the information extracted through NLP could enrich the knowledge of rare diseases, and thereby, help to reduce the diagnostic delay and improve the treatment of rare diseases. The paper describes the selection of 1,041 texts to be included in the corpus, the annotation process and the annotation guidelines. The entities (disease, rare disease, symptom, sign and anaphor) and the relationships (produces, is a, is acron, is synon, increases risk of, anaphora) were annotated. The RareDis corpus contains more than 5,000 rare diseases and almost 6,000 clinical manifestations are annotated. Moreover, the Inter Annotator Agreement evaluation shows a relatively high agreement (F1-measure equal to 83.5% under exact match criteria for the entities and equal to 81.3% for the relations). Based on these results, this corpus is of high quality, supposing a significant step for the field since there is a scarcity of available corpus annotated with rare diseases. This could open the door to further NLP applications, which would facilitate the diagnosis and treatment of these rare diseases and, therefore, would improve dramatically the quality of life of these patients.


Assuntos
Qualidade de Vida , Doenças Raras , Diagnóstico Tardio , Humanos , Processamento de Linguagem Natural , Doenças Raras/diagnóstico
18.
J Biomed Inform ; 134: 104211, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36152950

RESUMO

OBJECTIVE: A significant number of recent articles in PubMed have full text available in PubMed Central®, and the availability of full texts has been consistently growing. However, it is not currently possible for a user to simultaneously query the contents of both databases and receive a single integrated search result. In this study, we investigate how to score full text articles given a multitoken query and how to combine those full text article scores with scores originating from abstracts and achieve an overall improved retrieval performance. MATERIALS AND METHODS: For scoring full text articles, we propose a method to combine information coming from different sections by converting the traditionally used BM25 scores into log odds ratio scores which can be treated uniformly. We further propose a method that successfully combines scores from two heterogenous retrieval sources - full text articles and abstract only articles - by balancing the contributions of their respective scores through a probabilistic transformation. We use PubMed click data that consists of queries sampled from PubMed user logs along with a subset of retrieved and clicked documents to train the probabilistic functions and to evaluate retrieval effectiveness. RESULTS AND CONCLUSIONS: Random ranking achieves 0.579 MAP score on our PubMed click data. BM25 ranking on PubMed abstracts improves the MAP by 10.6%. For full text documents, experiments confirm that BM25 section scores are of different value depending on the section type and are not directly comparable. Naïvely using the body text of articles along with abstract text degrades the overall quality of the search. The proposed log odds ratio scores normalize and combine the contributions of occurrences of query tokens in different sections. By including full text where available, we gain another 0.67%, or 7% relative improvement over abstract alone. We find an advantage in the more accurate estimate of the value of BM25 scores depending on the section from which they were produced. Taking the sum of top three section scores performs the best.


Assuntos
Gerenciamento de Dados , Armazenamento e Recuperação da Informação , PubMed
19.
J Shoulder Elbow Surg ; 31(5): 932-939, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34801715

RESUMO

BACKGROUND: This study aimed to determine the sensitivity and specificity of sterile shoulder needle aspiration and cultures obtained during arthroscopic and mini-open procedures for detecting periprosthetic shoulder infections using tissue cultures from revision surgery as the gold standard. METHODS: All shoulder arthroplasty patients who underwent a synovial fluid puncture between August 2012 and February 2018 were selected. In addition, arthroplasty patients with cultures obtained during arthroscopic or mini-open procedures between May 2014 and May 2021 were selected. When sterile punctures or biopsy procedures were followed by revision surgery with collection of 6 tissue cultures, patients were included in the study and efficacy measures were calculated. RESULTS: Fifty-six patients were included in this study (with 57 punctures) and underwent analysis of puncture results after exclusions. Positive puncture results were found for Cutibacterium acnes, Staphylococcus aureus, Staphylococcus hominis, Actinomyces neuii, and Proteus mirabilis. These puncture cultures showed a sensitivity of 20.0% and specificity of 90.6%. From May 2014 to May 2021, 51 biopsy procedures were performed (15 arthroscopic and 36 mini-open); 37 biopsy procedures were included in this study (12 arthroscopic and 25 mini-open) for analysis after exclusions. Positive culture results were found for C acnes, Staphylococcus epidermidis, Staphylococcus saccharolyticus, and Streptococcus species. Arthroscopic biopsy cultures showed a sensitivity of 60.0% and specificity of 85.7%. For the mini-open biopsy cultures, the sensitivity and specificity were 66.7% and 85.7%, respectively. CONCLUSIONS: Sterile punctures for culture have a low sensitivity and a high specificity for diagnosing periprosthetic shoulder infections. Tissue cultures obtained during mini-open and arthroscopic procedures have a higher sensitivity for detecting periprosthetic shoulder infections.


Assuntos
Artroplastia do Ombro , Infecções Relacionadas à Prótese , Articulação do Ombro , Artroplastia do Ombro/efeitos adversos , Artroscopia , Humanos , Infecções Relacionadas à Prótese/microbiologia , Punções , Reoperação , Estudos Retrospectivos , Ombro/cirurgia , Articulação do Ombro/patologia
20.
Sensors (Basel) ; 22(1)2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35009945

RESUMO

A large number of power meters have become commercially available during the last decades to provide power output (PO) measurement. Some of these power meters were evaluated for validity in the literature. This study aimed to perform a review of the available literature on the validity of cycling power meters. PubMed, SPORTDiscus, and Google Scholar have been explored with PRISMA methodology. A total of 74 studies have been extracted for the reviewing process. Validity is a general quality of the measurement determined by the assessment of different metrological properties: Accuracy, sensitivity, repeatability, reproducibility, and robustness. Accuracy was most often studied from the metrological property (74 studies). Reproducibility was the second most studied (40 studies) property. Finally, repeatability, sensitivity, and robustness were considerably less studied with only 7, 5, and 5 studies, respectively. The SRM power meter is the most used as a gold standard in the studies. Moreover, the number of participants was very different among them, from 0 (when using a calibration rig) to 56 participants. The PO tested was up to 1700 W, whereas the pedalling cadence ranged between 40 and 180 rpm, including submaximal and maximal exercises. Other exercise conditions were tested, such as torque, position, temperature, and vibrations. This review provides some caveats and recommendations when testing the validity of a cycling power meter, including all of the metrological properties (accuracy, sensitivity, repeatability, reproducibility, and robustness) and some exercise conditions (PO range, sprint, pedalling cadence, torque, position, participant, temperature, vibration, and field test).


Assuntos
Ciclismo , Teste de Esforço , Exercício Físico , Humanos , Reprodutibilidade dos Testes , Torque
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