141 research outputs found
Multi-classifier prediction of knee osteoarthritis progression from incomplete imbalanced longitudinal data
Conventional inclusion criteria used in osteoarthritis clinical trials are
not very effective in selecting patients who would benefit from a therapy being
tested. Typically majority of selected patients show no or limited disease
progression during a trial period. As a consequence, the effect of the tested
treatment cannot be observed, and the efforts and resources invested in running
the trial are not rewarded. This could be avoided, if selection criteria were
more predictive of the future disease progression.
In this article, we formulated the patient selection problem as a multi-class
classification task, with classes based on clinically relevant measures of
progression (over a time scale typical for clinical trials). Using data from
two long-term knee osteoarthritis studies OAI and CHECK, we tested multiple
algorithms and learning process configurations (including multi-classifier
approaches, cost-sensitive learning, and feature selection), to identify the
best performing machine learning models. We examined the behaviour of the best
models, with respect to prediction errors and the impact of used features, to
confirm their clinical relevance. We found that the model-based selection
outperforms the conventional inclusion criteria, reducing by 20-25% the number
of patients who show no progression. This result might lead to more efficient
clinical trials.Comment: 22 pages, 12 figures, 10 table
Predicted and actual 2-year structural and pain progression in the IMI-APPROACH knee osteoarthritis cohort
ClinicalTrials.gov, https://clinicaltrials.gov, NCT03883568[Abstract] Objectives: The IMI-APPROACH knee osteoarthritis study used machine learning (ML) to predict structural and/or pain progression, expressed by a structural (S) and pain (P) predicted-progression score, to select patients from existing cohorts. This study evaluates the actual 2-year progression within the IMI-APPROACH, in relation to the predicted-progression scores.
Methods: Actual structural progression was measured using minimum joint space width (minJSW). Actual pain (progression) was evaluated using the Knee injury and Osteoarthritis Outcomes Score (KOOS) pain questionnaire. Progression was presented as actual change (Δ) after 2 years, and as progression over 2 years based on a per patient fitted regression line using 0, 0.5, 1 and 2-year values. Differences in predicted-progression scores between actual progressors and non-progressors were evaluated. Receiver operating characteristic (ROC) curves were constructed and corresponding area under the curve (AUC) reported. Using Youden's index, optimal cut-offs were chosen to enable evaluation of both predicted-progression scores to identify actual progressors.
Results: Actual structural progressors were initially assigned higher S predicted-progression scores compared with structural non-progressors. Likewise, actual pain progressors were assigned higher P predicted-progression scores compared with pain non-progressors. The AUC-ROC for the S predicted-progression score to identify actual structural progressors was poor (0.612 and 0.599 for Δ and regression minJSW, respectively). The AUC-ROC for the P predicted-progression score to identify actual pain progressors were good (0.817 and 0.830 for Δ and regression KOOS pain, respectively).
Conclusion: The S and P predicted-progression scores as provided by the ML models developed and used for the selection of IMI-APPROACH patients were to some degree able to distinguish between actual progressors and non-progressors
Local representative democracy and protest politics:the case of the Five-star Movement
In recent years, protest politics has become a relevant phenomenon in various European countries. Italy has witnessed the rise of the Five-star Movement (M5S), an anti-establishment party, which, at the 2013 general election, obtained one-fourth of the total votes. However, the story of this ‘party-movement’ started at the local level, as a civic network aimed at changing administrative practices in municipal government. By using an original dataset on representation in 671 Italian municipalities from 2010 to 2014, this article aims to explain not only the subnational political success of the M5S but also the challenges and contradictions that a newly formed movement faces in multi-level electoral arenas
Neuropathic Pain in the IMI-APPROACH Knee Osteoarthritis Cohort: Prevalence and Phenotyping
The study is registered under clinicaltrials.gov nr: NCT03883568.[Abstract] Objectives: Osteoarthritis (OA) patients with a neuropathic pain (NP) component may represent a specific phenotype. This study compares joint damage, pain and functional disability between knee OA patients with a likely NP component, and those without a likely NP component.
Methods: Baseline data from the Innovative Medicines Initiative Applied Public-Private Research enabling OsteoArthritis Clinical Headway knee OA cohort study were used. Patients with a painDETECT score ≥19 (with likely NP component, n=24) were matched on a 1:2 ratio to patients with a painDETECT score ≤12 (without likely NP component), and similar knee and general pain (Knee Injury and Osteoarthritis Outcome Score pain and Short Form 36 pain). Pain, physical function and radiographic joint damage of multiple joints were determined and compared between OA patients with and without a likely NP component.
Results: OA patients with painDETECT scores ≥19 had statistically significant less radiographic joint damage (p≤0.04 for Knee Images Digital Analysis parameters and Kellgren and Lawrence grade), but an impaired physical function (p<0.003 for all tests) compared with patients with a painDETECT score ≤12. In addition, more severe pain was found in joints other than the index knee (p≤0.001 for hips and hands), while joint damage throughout the body was not different.
Conclusions: OA patients with a likely NP component, as determined with the painDETECT questionnaire, may represent a specific OA phenotype, where local and overall joint damage is not the main cause of pain and disability. Patients with this NP component will likely not benefit from general pain medication and/or disease-modifying OA drug (DMOAD) therapy. Reserved inclusion of these patients in DMOAD trials is advised in the quest for successful OA treatments
Not saying, not doing: Convergences, contingencies and causal mechanisms of state reform and decentralisation in Hollande’s France
Are States in contemporary Europe subject to new forms of convergence under the impact of economic crisis, enhanced European steering and international monitoring? Or is the evolution of governance (national and sub-national) driven fundamentally by diverging, mainly domestic pressures? Drawing on extensive new data, the article combines analysis of the State Modernisation and Decentralisation reform programmes of the Hollande–Ayrault administration, drawing comparisons where appropriate with the previous Sarkozy regime. The limits of President Hollande’s anti-Sarkozy method were demonstrated in the first 2 years; framing state reform and decentralisation in negative terms prevented the emergence of a coherent legitimising discourse. The empirical data is interpreted with reference to a comparative ‘States of Convergence’ framework, which is conceptualised as a heuristic device for analysing variation between places, countries and policy fields. The article concludes that the forces of hard convergence are gaining ground, as economic, epistemic and European pressures continually challenge the forces of institutional inertia
Common genetic variation in the Estrogen Receptor Beta (ESR2) gene and osteoarthritis: results of a meta-analysis
Background: The objective of this study was to examine the relationship between common genetic variation of the ESR2 gene and osteoarthritis.Methods: In the discovery study, the Rotterdam Study-I, 7 single nucleotide polymorphisms (SNPs) were genotyped and tested for association with hip (284 cases, 2772 controls), knee (665 cases, 2075 controls), and hand OA (874 cases, 2184 controls) using an additive model. In the replication stage one SNP (rs1256031) was tested in an additional 2080 hip, 1318 knee and 557 hand OA cases and 4001, 2631 and 1699 controls respectively. Fixed- and random-effects meta-analyses were performed over the complete dataset including 2364 hip, 1983 knee and 1431 hand OA cases and approximately 6000 controls.Results: The C allele of rs1256031 was associated with a 36% increased odds of hip OA in women of the Rotterdam Study-I (OR 1.36, 95% CI 1.08-1.70, p = 0.009). Haplotype analysis and analysis of knee- and hand OA did not give additional information. With the replication studies, the meta-analysis did not show a significant effect of this SNP on hip OA in the total population (OR 1.06, 95% CI 0.99-1.15, p = 0.10). Stratification according to gender did not change the results. In this study, we had 80% power to detect an odds ratio of at least 1.14 for hip OA (α = 0.05).Conclusion: This study showed that common genetic variation in the ESR2 gene is not likely to influence the risk of osteoarthritis with effects smaller than a 13% increase
Understanding political responsibility in corporate citizenship: towards a shared responsibility for the common good
In this article, we explore the debate on corporate citizenship and the role of business in global governance. In the debate on political corporate social responsibility it is assumed that under globalization business is taking up a greater political role. Apart from economic responsibilities firms assume political responsibilities taking up traditional governmental tasks such as regulation of business and provision of public goods. We contrast this with a subsidiarity-based approach to governance, in which firms are seen as intermediate actors who have political co-responsibilities in society endowed upon them by (inter)national governmental institutions. We argue that both approaches face conceptual and empirical problems, and do not make clear the content and scope of political corporate responsibility. Based on Iris Marion Young’s account of political responsibility we argue that corporate actors and governmental actors have a shared responsibility to tackle societal problems. Taking political corporate responsibility not only entails engaging in private action or engaging in public–private partnerships, but it also includes aiding governmental actors to remedy injustice or even create public institutions where they do not yet exist. By adding this perspective we contribute to the debate on responsibility in corporate citizenship and clarify the political role business can play in global governance.</p
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