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1.
Scand J Psychol ; 65(2): 339-345, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37951843

RESUMO

INTRODUCTION: Mastery goals (aims to learn or attain skill) have traditionally been portrayed in achievement-motivation literature as the optimal goal for ensuring objective performance and well-being outcomes (relative to performance goals - aims to outperform others). This portrayal often yielded the recommendation that those in applied settings, such as coaches, managers, and teachers, should encourage those whom they lead to pursue mastery goals. We put this assertion to a test by examining whether the effect of situationally induced goals depends on the goals that individuals personally self-adopt. METHODS: We hypothesized that inducing mastery goals would be beneficial for individuals who self-adopt performance goals (Hypothesis 1), while inducing performance goals would be beneficial for individuals who self-adopt mastery goals (Hypothesis 2). We conducted an experiment among amateur field hockey players to test these hypotheses in a scoring exercise. RESULTS: We found that encouraging a mastery goal (compared with a performance goal) led to higher scoring accuracy among players high in self-adopted performance goals (supporting Hypothesis 1) but also unexpectedly for individuals low in self-adopted mastery goals. We did not find support for Hypothesis 2. CONCLUSION: The findings indicate that situationally inducing a mastery goal may be beneficial for individuals who do not already self-adopt mastery goals strongly.


Assuntos
Objetivos , Motivação , Humanos , Logro , Aprendizagem , Exercício Físico
2.
Nat Med ; 29(7): 1814-1820, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37460754

RESUMO

Predictive artificial intelligence (AI) systems based on deep learning have been shown to achieve expert-level identification of diseases in multiple medical imaging settings, but can make errors in cases accurately diagnosed by clinicians and vice versa. We developed Complementarity-Driven Deferral to Clinical Workflow (CoDoC), a system that can learn to decide between the opinion of a predictive AI model and a clinical workflow. CoDoC enhances accuracy relative to clinician-only or AI-only baselines in clinical workflows that screen for breast cancer or tuberculosis (TB). For breast cancer screening, compared to double reading with arbitration in a screening program in the UK, CoDoC reduced false positives by 25% at the same false-negative rate, while achieving a 66% reduction in clinician workload. For TB triaging, compared to standalone AI and clinical workflows, CoDoC achieved a 5-15% reduction in false positives at the same false-negative rate for three of five commercially available predictive AI systems. To facilitate the deployment of CoDoC in novel futuristic clinical settings, we present results showing that CoDoC's performance gains are sustained across several axes of variation (imaging modality, clinical setting and predictive AI system) and discuss the limitations of our evaluation and where further validation would be needed. We provide an open-source implementation to encourage further research and application.


Assuntos
Inteligência Artificial , Triagem , Reprodutibilidade dos Testes , Fluxo de Trabalho , Humanos
3.
Nat Biomed Eng ; 7(6): 756-779, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37291435

RESUMO

Machine-learning models for medical tasks can match or surpass the performance of clinical experts. However, in settings differing from those of the training dataset, the performance of a model can deteriorate substantially. Here we report a representation-learning strategy for machine-learning models applied to medical-imaging tasks that mitigates such 'out of distribution' performance problem and that improves model robustness and training efficiency. The strategy, which we named REMEDIS (for 'Robust and Efficient Medical Imaging with Self-supervision'), combines large-scale supervised transfer learning on natural images and intermediate contrastive self-supervised learning on medical images and requires minimal task-specific customization. We show the utility of REMEDIS in a range of diagnostic-imaging tasks covering six imaging domains and 15 test datasets, and by simulating three realistic out-of-distribution scenarios. REMEDIS improved in-distribution diagnostic accuracies up to 11.5% with respect to strong supervised baseline models, and in out-of-distribution settings required only 1-33% of the data for retraining to match the performance of supervised models retrained using all available data. REMEDIS may accelerate the development lifecycle of machine-learning models for medical imaging.


Assuntos
Aprendizado de Máquina , Aprendizado de Máquina Supervisionado , Diagnóstico por Imagem
4.
Med Image Anal ; 75: 102274, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34731777

RESUMO

Supervised deep learning models have proven to be highly effective in classification of dermatological conditions. These models rely on the availability of abundant labeled training examples. However, in the real-world, many dermatological conditions are individually too infrequent for per-condition classification with supervised learning. Although individually infrequent, these conditions may collectively be common and therefore are clinically significant in aggregate. To prevent models from generating erroneous outputs on such examples, there remains a considerable unmet need for deep learning systems that can better detect such infrequent conditions. These infrequent 'outlier' conditions are seen very rarely (or not at all) during training. In this paper, we frame this task as an out-of-distribution (OOD) detection problem. We set up a benchmark ensuring that outlier conditions are disjoint between the model training, validation, and test sets. Unlike traditional OOD detection benchmarks where the task is to detect dataset distribution shift, we aim at the more challenging task of detecting subtle differences resulting from a different pathology or condition. We propose a novel hierarchical outlier detection (HOD) loss, which assigns multiple abstention classes corresponding to each training outlier class and jointly performs a coarse classification of inliers vs. outliers, along with fine-grained classification of the individual classes. We demonstrate that the proposed HOD loss based approach outperforms leading methods that leverage outlier data during training. Further, performance is significantly boosted by using recent representation learning methods (BiT, SimCLR, MICLe). Further, we explore ensembling strategies for OOD detection and propose a diverse ensemble selection process for the best result. We also perform a subgroup analysis over conditions of varying risk levels and different skin types to investigate how OOD performance changes over each subgroup and demonstrate the gains of our framework in comparison to baseline. Furthermore, we go beyond traditional performance metrics and introduce a cost matrix for model trust analysis to approximate downstream clinical impact. We use this cost matrix to compare the proposed method against the baseline, thereby making a stronger case for its effectiveness in real-world scenarios.


Assuntos
Dermatologia , Benchmarking , Humanos
5.
Nat Med ; 26(6): 892-899, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32424211

RESUMO

Progression to exudative 'wet' age-related macular degeneration (exAMD) is a major cause of visual deterioration. In patients diagnosed with exAMD in one eye, we introduce an artificial intelligence (AI) system to predict progression to exAMD in the second eye. By combining models based on three-dimensional (3D) optical coherence tomography images and corresponding automatic tissue maps, our system predicts conversion to exAMD within a clinically actionable 6-month time window, achieving a per-volumetric-scan sensitivity of 80% at 55% specificity, and 34% sensitivity at 90% specificity. This level of performance corresponds to true positives in 78% and 41% of individual eyes, and false positives in 56% and 17% of individual eyes at the high sensitivity and high specificity points, respectively. Moreover, we show that automatic tissue segmentation can identify anatomical changes before conversion and high-risk subgroups. This AI system overcomes substantial interobserver variability in expert predictions, performing better than five out of six experts, and demonstrates the potential of using AI to predict disease progression.


Assuntos
Aprendizado Profundo , Atrofia Geográfica/diagnóstico por imagem , Tomografia de Coerência Óptica , Degeneração Macular Exsudativa/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Diagnóstico Precoce , Intervenção Médica Precoce , Feminino , Humanos , Imageamento Tridimensional , Degeneração Macular/diagnóstico por imagem , Masculino , Prognóstico , Degeneração Macular Exsudativa/diagnóstico por imagem , Degeneração Macular Exsudativa/terapia
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