scholarly journals T107. INDIVIDUALIZED DIAGNOSTIC AND PROGNOSTIC MODELS FOR PATIENTS WITH PSYCHOSIS RISK SYNDROMES: A META-ANALYTIC VIEW ON THE STATE-OF-THE-ART

2020 ◽  
Vol 46 (Supplement_1) ◽  
pp. S271-S272
Author(s):  
Rachele Sanfelici ◽  
Dominic Dwyer ◽  
Linda A Antonucci ◽  
Nikolaos Koutsouleris
Keyword(s):  
Publication Bias ◽  
Cox Regression ◽  
State Of The Art ◽  
External Validation ◽  
Age Distribution ◽  
Research Field ◽  
The State ◽  
Prognostic Models ◽  
Neurocognitive Performance

Abstract Background The Clinical High Risk (CHR) paradigm has led research into the biological and clinical underpinnings of the risk for psychosis, aiming at predicting and possibly preventing transition to the disorder. Statistical methods like machine learning (ML) and Cox proportional hazard regression have enabled the construction of diagnostic and prognostic models based on different data modalities, e.g., clinical risk factors, neurocognitive performance, or neurobiological data. However, their translation to clinical practice is still hindered by the heterogeneity both of CHR populations and methodologies. One way to tackle this issue is to use a meta-analytic approach to quantitatively investigate models’ performance throughout different outcomes, algorithms and data modalities. The aim of this work was, thus, to investigate the effects of (I) data modality, (II) type of algorithm, and (III) validation paradigms on prognostic and diagnostic models’ performance. We expect our results to facilitate a deeper understanding of the state-of-the-art within the CHR research field and clarify the methodological bottlenecks that impede the clinical translation of diagnostic and prognostic tools. Methods We systematically reviewed the literature on diagnostic and prognostic models built on Cox regression and ML. Further, we conducted a meta-analysis on accuracy performances investigating effects of the following moderators: age, sex, data modality, algorithm, presence of cross-validation (CV), being a multisite study and year of publication. For prognostic studies we investigated also follow-up time and prognostic target. All analyses were conducted with R v3.6.0. and results were corrected for False Discovery Rate. Results 44 articles were included for a total of 3707 individuals for prognostic and 1052 for diagnostic studies (572 CHR and 480 healthy controls, HC). CHR could be classified against HC with 78% sensitivity (95%-CI: 63%-83%) and 77% specificity (95%-CI: 68%-84%). Across prognostic models, sensitivity reached 67% (95%-CI: 63%-70%) and specificity 78% (95%-CI: 73%-82%). Our results point to a higher sensitivity of ML models compared to Cox regression in prognostic studies (p = .009; χ2(2) = 6.96, p = 0.031). This effect was collinear with that of CV, due to the overlap of this factor with algorithm type. Notably, there was a publication bias for prognostic studies (R2 = 0.26, p < .001), yet no significant effects of data modality, CHR or CV type, prognostic target, or any other confounding variable (e.g., age distribution, sex, year of publication or follow-up interval time) on accuracy performance. Discussion Our results point to a good models’ performance overall and no effects of data modality or patient population. ML outperformed Cox regression in prognostic studies, these, however, showing a publication bias. These results may be driven by substantial clinical and methodological heterogeneity currently affecting several aspects of the CHR field. A comprehensive change within the current CHR paradigm is required to enable the clinical application of diagnostic and prognostic models for the at-risk state. First, the field requires study design harmonization, which demands, for instance, reliable methodological approaches like cross- or external validation to ensure generalizability. Second, efforts may be made in unifying the CHR definition, both theoretically and practically, and also embrace relevant non-transition outcomes to broaden the prognostic scope. Future studies are needed to investigate whether harmonising procedures within precision psychiatry will lead to more reliable and reproducible translational research in the field.

AUTOMATIC SIGNATURE VERIFICATION: THE STATE OF THE ART—1989–1993

1994 ◽  
Vol 08 (03) ◽  
pp. 643-660 ◽  
Author(s):  
FRANCK LECLERC ◽  
RÉJEAN PLAMONDON
Keyword(s):  
Neural Network ◽  
State Of The Art ◽  
The State ◽  
Signature Verification ◽  
Writer Identification ◽  
Network Approaches

This paper is a follow up to an article published in 1989 by R. Plamondon and G. Lorette on the state of the art in automatic signature verification and writer identification. It summarizes the activity from year 1989 to 1993 in automatic signature verification. For this purpose, we report on the different projects dealing with dynamic, static and neural network approaches. In each section, a brief description of the major investigations is given.

Development and validation of prognostic models in patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib: A Greek-French collaboration.

2012 ◽  
Vol 30 (15_suppl) ◽  
pp. e15040-e15040
Author(s):  
Vasilios Karavasilis ◽  
Kimon Tzanis ◽  
Christina Bamia ◽  
Reza-Thierry Elaidi ◽  
Efthimios Kostouros ◽  
...  
Keyword(s):  
Kinase Inhibitors ◽  
Cox Regression ◽  
External Validation ◽  
Prognostic Index ◽  
Roc Curves ◽  
Risk Groups ◽  
High Risk Group ◽  
Prognostic Models ◽  
Clinical Factors ◽  
Complicated Model

e15040 Background: The use of tyrosine kinase inhibitors (TKIs) in mRCC has improved prognosis but the individual outcome remains largely unpredictable. The MSKCC model, used to identify risk groups, was developed in cytokine-treated patients and has not been externally validated in the TKI era. It contains 3 laboratory factors (total 5), making its application to retrospective series somewhat problematic. Subsequently, a more complicated model, using 4 laboratory factors (total 6) has been described. The Hellenic Cooperative Oncology Group recently described a simpler model with only 3 clinical factors. We are describing the application and external validation of this model. Methods: 128 Greek patients with mRCC treated with 1st line sunitinib were included. All had had nephrectomy. Previous interferon was allowed. Cox regression was used to develop a predictive model for overall survival (OS). Our model was compared to that of MSKCC and Heng’s using ROC curves and Harrell’s Concordance Index. Risk groups were defined by the calculated prognostic index and by clinical factors. External validation was done using a sample of 226 French patients. The Royston and Sauerbrei D statistic was used as a measure of discrimination of the survival model. Results: Time from diagnosis of RCC to start of sunitinib (<12), PS (>1) and number of metastatic sites (>1) were independent adverse prognostic factors in the Greek dataset. The co-efficients for each factor were: 0.51, 0.97, 0.61, respectively. The 3 risk groups were defined by the 25th and 75th percentiles of the prognostic index values (Table 1). The model was of equal prognostic value to the MSKCC (p=.272) and Heng’s (p=.075). French had better survival than Greek patients especially in the high risk group (for all models). Validation of our model in the French data showed that it was applicable (R2 D: 0.14, SE: 0.09), especially for the low/medium risk groups. Conclusions: Our model is the only one externally validated in TKI-treated patients. It may be considered as a simpler alternative to those currently applied. [Table: see text]

scholarly journals Research on esotericism in Scandinavia

2008 ◽  
Vol 20 ◽  
pp. 38-49
Author(s):  
Henrik Bogdan ◽  
Olav Hammer
Keyword(s):  
Present Article ◽  
State Of The Art ◽  
Research Field ◽  
The State ◽  
Academic Careers ◽  
The Other ◽  
Scandinavian Language ◽  
Western Esotericism ◽  
Language Literature

The title of this paper can be understood in two senses. In the sense of ‘research on esotericism carried out by Scandinavian scholars’, the field is blossoming. Several dozen individuals, at various points in their academic careers, are pursuing research on some aspect of Western esotericism however the concept is defined. In the other conceivable sense, ‘research on Scandinavian esotericism’, the availability of academic studies is generally more limited. The purpose of the present article is to survey the state of the art of this research field, especially pertaining to esotericism in Sweden (the country we are most familiar with), and to provide a rough map of the Scandinavian-language literature, especially for the benefit of non-Scandinavian readers.

scholarly journals A Nomogram to Predict Stricture-free Survival in Patients with Ureteral Stricture after Balloon Dilation

2021 ◽  
Author(s):  
Jintao Hu ◽  
Cong Lai ◽  
Mingchao Gao ◽  
Kaiwen Li ◽  
Wang He ◽  
...  
Keyword(s):  
Cox Regression ◽  
External Validation ◽  
Balloon Dilation ◽  
Postoperative Recurrence ◽  
Ureteral Stricture ◽  
Free Survival ◽  
Actual Observation ◽  
Balloon Size ◽  
Multivariable Analyses

Abstract Background Balloon dilation is a commonly used minimally invasive endourological treatment of ureteral stricture, but the postoperative recurrence rate is relatively high. And factors contributing to recurrence after treatment are poorly understood. Herein, we sought to develop a novel clinical nomogram to predict ureteral stricture-free survival in patients suffering from ureter stricture and performed balloon dilation. Methods The nomogram was established based on a retrospective analysis of 321 patients diagnosed with ureter strictures from January 2016 to January 2020 in Sun Yat-sen Memorial Hospital using the Cox regression model. Perioperative clinical data and disease outcomes were analyzed. Discrimination of the nomogram was assessed by the concordance index (C-index) and the calibration curve. The results were internally validated using bootstrap resampling. Results Overall, 321 patients with a median follow-up of 590 days were enrolled in the study, among which 97 patients (30.2%) developed recurrence of ureteral stricture during follow-up. Five variables remained significant predictors of ureteral re-stricture after multivariable analyses: stricture nature (P < 0.001), urinary nitrite (P = 0.041), CKD (P = 0.005), stent retention time (P < 0.001), and balloon size (P = 0.029). The calibration craves for the probability of 1-, 3-, and 5-years stricture-free survival (SFS) presented satisfied with the consistency of nomogram prediction and actual observation. The C-index of the model was 0.74 (95% CI 0.70–0.79). Conclusions Our study developed the first nomogram to effectively predict stricture-free survival in patients suffering from ureter stricture after balloon dilation. It is helpful to identify the optimal patients with ureter stricture for balloon dilation and improve treatment outcomes. However, further external validation of the nomogram is warranted.

Named-entity recognition for early modern textual documents: a review of capabilities and challenges with strategies for the future

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Marco Humbel ◽  
Julianne Nyhan ◽  
Andreas Vlachidis ◽  
Kim Sloan ◽  
Alexandra Ortolja-Baird
Keyword(s):  
Early Modern ◽  
State Of The Art ◽  
Named Entity Recognition ◽  
Research Field ◽  
The State ◽  
Entity Recognition ◽  
British Library ◽  
Extensive Literature ◽  
Content Type ◽  
Named Entity

PurposeBy mapping-out the capabilities, challenges and limitations of named-entity recognition (NER), this article aims to synthesise the state of the art of NER in the context of the early modern research field and to inform discussions about the kind of resources, methods and directions that may be pursued to enrich the application of the technique going forward.Design/methodology/approachThrough an extensive literature review, this article maps out the current capabilities, challenges and limitations of NER and establishes the state of the art of the technique in the context of the early modern, digitally augmented research field. It also presents a new case study of NER research undertaken by Enlightenment Architectures: Sir Hans Sloane's Catalogues of his Collections (2016–2021), a Leverhulme funded research project and collaboration between the British Museum and University College London, with contributing expertise from the British Library and the Natural History Museum.FindingsCurrently, it is not possible to benchmark the capabilities of NER as applied to documents of the early modern period. The authors also draw attention to the situated nature of authority files, and current conceptualisations of NER, leading them to the conclusion that more robust reporting and critical analysis of NER approaches and findings is required.Research limitations/implicationsThis article examines NER as applied to early modern textual sources, which are mostly studied by Humanists. As addressed in this article, detailed reporting of NER processes and outcomes is not necessarily valued by the disciplines of the Humanities, with the result that it can be difficult to locate relevant data and metrics in project outputs. The authors have tried to mitigate this by contacting projects discussed in this paper directly, to further verify the details they report here.Practical implicationsThe authors suggest that a forum is needed where tools are evaluated according to community standards. Within the wider NER community, the MUC and ConLL corpora are used for such experimental set-ups and are accompanied by a conference series, and may be seen as a useful model for this. The ultimate nature of such a forum must be discussed with the whole research community of the early modern domain.Social implicationsNER is an algorithmic intervention that transforms data according to certain rules-, patterns- or training data and ultimately affects how the authors interpret the results. The creation, use and promotion of algorithmic technologies like NER is not a neutral process, and neither is their output A more critical understanding of the role and impact of NER on early modern documents and research and focalization of some of the data- and human-centric aspects of NER routines that are currently overlooked are called for in this paper.Originality/valueThis article presents a state of the art snapshot of NER, its applications and potential, in the context of early modern research. It also seeks to inform discussions about the kinds of resources, methods and directions that may be pursued to enrich the application of NER going forward. It draws attention to the situated nature of authority files, and current conceptualisations of NER, and concludes that more robust reporting of NER approaches and findings are urgently required. The Appendix sets out a comprehensive summary of digital tools and resources surveyed in this article.

Racial phenotypes in moyamoya disease: a comparative analysis of clinical presentation and natural history in a single multiethnic cohort of 250 hemispheres

2020 ◽  
Vol 133 (6) ◽  
pp. 1766-1772 ◽  
Author(s):  
James Feghali ◽  
Risheng Xu ◽  
Wuyang Yang ◽  
Jason Liew ◽  
Rafael J. Tamargo ◽  
...  
Keyword(s):  
Natural History ◽  
Functional Outcome ◽  
Moyamoya Disease ◽  
Cox Regression ◽  
Relative Rate ◽  
Statistical Significance ◽  
Age Distribution ◽  
Stroke Incidence ◽  
Asian Patients

OBJECTIVEThe authors aimed to determine whether differences exist in presentation and natural history when comparing Asian patients with moyamoya disease (MMD) to those of other ethnicities in North America.METHODSA database of 137 patients with MMD presenting to their institution between 1994 and 2015 was reviewed. Baseline characteristics and outcome variables, including stroke and functional outcome, were compared between Asian and non-Asian patients. Unadjusted Kaplan-Meier survival analysis and adjusted Cox regression models were used to compare stroke-free survival and stroke hazard after diagnosis among hemispheres of both racial groups. The analysis was stratified by age group, and censoring was performed until last follow-up or at the time of surgery. Because the relative rate of stroke changed between Asian and non-Asian adults after 1.5 years of follow-up, a time-segmented analysis focusing on the period 1.5 years after diagnosis was performed.RESULTSThe cohort comprised 23% (31/137) Asian and 77% (106/137) non-Asian patients with MMD with a bimodal age distribution. Non-Asian patients had a higher prevalence of increased BMI (p = 0.02) and smoking (p = 0.04). Among patients who presented with stroke (n = 90), hemorrhage was significantly more common among Asians (p = 0.02). The natural history analysis included 250 hemispheres: 67 pediatric and 183 adult hemispheres. The overall mean follow-up duration since diagnosis was 3.3 years. Among adults, Asian patients had a higher incidence of stroke (8.0 per 100 person-years vs 3.0 per 100 person-years) over a mean follow-up of 3.3 years, but results were not statistically significant (p = 0.45). In the period beginning 1.5 years after diagnosis, Asian adults had a significantly higher hazard of stroke over a mean follow-up of 7.7 years, while controlling for sex, hypertension, and stroke before diagnosis (hazard ratio 8.8, p = 0.02). Among pediatric patients, Asians also had a higher stroke incidence (10.0 per 100 person-years vs 3.5 per 100 person-years) over a mean follow-up of 3.2 years; however, results did not reach statistical significance (p = 0.40). Functional outcome was similar between both ethnic groups at last follow-up (p = 0.57).CONCLUSIONSThis study suggests a comparatively more progressive course of MMD in Asians. Further studies are required to fully characterize the phenotypic distinctions between different races and underlying pathophysiological mechanisms.

scholarly journals Text Augmentation Using BERT for Image Captioning

2020 ◽  
Vol 10 (17) ◽  
pp. 5978
Author(s):  
Viktar Atliha ◽  
Dmitrij Šešok
Keyword(s):  
Neural Networks ◽  
Human Computer Interaction ◽  
State Of The Art ◽  
Language Model ◽  
Research Field ◽  
The State ◽  
Training Dataset ◽  
Image Description ◽  
Image Captioning ◽  
Training Set

Image captioning is an important task for improving human-computer interaction as well as for a deeper understanding of the mechanisms underlying the image description by human. In recent years, this research field has rapidly developed and a number of impressive results have been achieved. The typical models are based on a neural networks, including convolutional ones for encoding images and recurrent ones for decoding them into text. More than that, attention mechanism and transformers are actively used for boosting performance. However, even the best models have a limit in their quality with a lack of data. In order to generate a variety of descriptions of objects in different situations you need a large training set. The current commonly used datasets although rather large in terms of number of images are quite small in terms of the number of different captions per one image. We expanded the training dataset using text augmentation methods. Methods include augmentation with synonyms as a baseline and the state-of-the-art language model called Bidirectional Encoder Representations from Transformers (BERT). As a result, models that were trained on a datasets augmented show better results than that models trained on a dataset without augmentation.

scholarly journals A nomogram to predict stricture-free survival in patients with ureteral stricture after balloon dilation

BMC Urology ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jintao Hu ◽  
Cong Lai ◽  
Mingchao Gao ◽  
Kaiwen Li ◽  
Wang He ◽  
...  
Keyword(s):  
Cox Regression ◽  
External Validation ◽  
Balloon Dilation ◽  
Postoperative Recurrence ◽  
Ureteral Stricture ◽  
Free Survival ◽  
Actual Observation ◽  
Balloon Size ◽  
Multivariable Analyses

Abstract Background Balloon dilation is a commonly used minimally invasive endourological treatment of ureteral stricture, but the postoperative recurrence rate is relatively high. And factors contributing to recurrence after treatment are poorly understood. Herein, we sought to develop a novel clinical nomogram to predict ureteral stricture-free survival in patients suffering from ureter stricture and performed balloon dilation. Methods The nomogram was established based on a retrospective analysis of 321 patients who received endoscopic balloon dilation alone for ureter strictures from January 2016 to January 2020 in Sun Yat-sen Memorial Hospital using the Cox regression model. Perioperative clinical data and disease outcomes were analyzed. The primary endpoint was the onset of ureteral re-stricture after ureter balloon dilation. Discrimination of the nomogram was assessed by the concordance index (C-index) and the calibration curve. The results were internally validated using bootstrap resampling. Results Overall, 321 patients with a median follow-up of 590 days were enrolled in the study, among which 97 patients (30.2%) developed recurrence of ureteral stricture during follow-up. Five variables remained significant predictors of ureteral re-stricture after multivariable analyses: stricture nature (P < 0.001), urinary nitrite (P = 0.041), CKD (P = 0.005), stent retention time (P < 0.001), and balloon size (P = 0.029). The calibration craves for the probability of 1-, 3-, and 5-years stricture-free survival (SFS) presented satisfied with the consistency of nomogram prediction and actual observation. The C-index of the model was 0.74 (95% CI 0.70–0.79). Conclusions Our study developed the first nomogram to effectively predict stricture-free survival in patients suffering from ureter stricture after balloon dilation. It is helpful to identify the optimal patients with ureter stricture for balloon dilation and improve treatment outcomes. However, further external validation of the nomogram is warranted.

scholarly journals Process of change: states, transitions, and determinants

2021 ◽  
Vol Volume 9, Number 1, Special... (Special Issue...) ◽  
Author(s):  
Alessandro Fenicio ◽  
Yann Laurillau ◽  
Gaëlle Calvary
Keyword(s):  
Comparative Analysis ◽  
Scientific Literature ◽  
State Of The Art ◽  
Research Field ◽  
The State ◽  
Process Of Change ◽  
Example Analyse

The goal of persuasion is to change the behaviour or the attitude of a person without using any form of coercion (Oinas et al. 2010). In the last ten years, several models, approaches and theories have been developed in the research field of persuasion, producing a copious scientific literature. Different reviews of the state-of-the-art focusing on specific aspects have been proposed. Pindel et al. (Pinder et al. 2018) for example analyse the state of the art under the perspective of the mechanisms that lead to the habit forming. In this work, we report a state-of-the-art review on the key elements of the process of change using the concepts of states, transitions, and determinants to propose a common generic paradigm. We conclude with a discussion about the operationalization of persuasive processes and with a comparative analysis on the reviewed theories. Si le but et les garde-fous éthiques de la persuasion sont aujourd’hui bien compris, la littérature est abondante et les analyses critiques multiples, sans qu’un langage de comparaison n’ait été défini. Cet article propose les concepts d’états, de transitions et de déterminants pour caractériser les travaux de la littérature et ainsi en faciliter la compréhension et la comparaison. L’opérationnalisation de ce cadre ouvre des perspectives intéressantes au domaine.

scholarly journals Prognostic models of diabetic microvascular complications: a systematic review and meta-analysis

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Sigit Ari Saputro ◽  
Oraluck Pattanaprateep ◽  
Anuchate Pattanateepapon ◽  
Swekshya Karmacharya ◽  
Ammarin Thakkinstian
Keyword(s):  
Systematic Review ◽  
Cox Regression ◽  
Meta Analysis ◽  
Microvascular Complications ◽  
External Validation ◽  
Prognostic Models ◽  
Discriminative Performance ◽  
Diabetic Microvascular Complications ◽  
Stage Renal Disease ◽  
End Stage

Abstract Background Many prognostic models of diabetic microvascular complications have been developed, but their performances still varies. Therefore, we conducted a systematic review and meta-analysis to summarise the performances of the existing models. Methods Prognostic models of diabetic microvascular complications were retrieved from PubMed and Scopus up to 31 December 2020. Studies were selected, if they developed or internally/externally validated models of any microvascular complication in type 2 diabetes (T2D). Results In total, 71 studies were eligible, of which 32, 30 and 18 studies initially developed prognostic model for diabetic retinopathy (DR), chronic kidney disease (CKD) and end stage renal disease (ESRD) with the number of derived equations of 84, 96 and 51, respectively. Most models were derived-phases, some were internal and external validations. Common predictors were age, sex, HbA1c, diabetic duration, SBP and BMI. Traditional statistical models (i.e. Cox and logit regression) were mostly applied, otherwise machine learning. In cohorts, the discriminative performance in derived-logit was pooled with C statistics of 0.82 (0.73‑0.92) for DR and 0.78 (0.74‑0.83) for CKD. Pooled Cox regression yielded 0.75 (0.74‑0.77), 0.78 (0.74‑0.82) and 0.87 (0.84‑0.89) for DR, CKD and ESRD, respectively. External validation performances were sufficiently pooled with 0.81 (0.78‑0.83), 0.75 (0.67‑0.84) and 0.87 (0.85‑0.88) for DR, CKD and ESRD, respectively. Conclusions Several prognostic models were developed, but less were externally validated. A few studies derived the models by using appropriate methods and were satisfactory reported. More external validations and impact analyses are required before applying these models in clinical practice. Systematic review registration PROSPERO CRD42018105287

Sign in / Sign up

Export Citation Format

Share Document