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Balance Billing as an Adherence to Treatment Signalling Device
No full textIn some countries, including France, patients can choose between consulting a physician working in the regulated sector where, in general, fees are fully covered by health insurance (whether public, private or mixed), or a physician working in the unregulated sector, where a balance billing scheme operates. In the latter, fees might not be fully covered by health insurance, and patients must make out-of-pocket payments. The paper analyses the signalling properties of this mechanism in a context where patients are heterogenous with respect to their propensity to adhere to the prescribed treatment. The model reveals that a small extra fee allows to obtain a separating equilibrium in which only patients with a high propensity to adhere to the treatment will opt for the unregulated sector and benefit of a higher care effort on behalf of their physician. We also analyse the other equilibria of the game and comment on their welfare properties
Pickup and delivery problems with autonomous vehicles on rings
No full textInternational audienceIn this paper we introduce a new class of Pickup and Delivery problems on circles (or rings). These problems arise in the field of public transportation systems where autonomous (i.e. driverless) vehicles travel on circular networks. We consider a set of stations arranged in a circle and a set of transportation requests. Each request asks for the transportation of a certain quantity from a pickup station to a delivery station. A fleet of capacitated vehicles is available at the depot. In the first part of the paper we propose a classification scheme for these problems. In the second part, we address the variants in which the vehicles are allowed to move in a single direction of the circle (either clockwise or counterclockwise) and the objective is to minimize the number of tours on the ring while serving all the requests. We provide a complexity analysis for this class of problems. We develop polynomial time algorithms for the variants that are polynomially solvable and proofs of NP-hardness for the variants that are NP-hard. In addition, for the latter, we provide mathematical formulations and perform computational tests that show the effectiveness of these formulations. Finally, we compare optimal solutions with those obtained using a straightforward greedy algorithm
Use of Complementary and Alternative Medicines by Patients with Psoriasis: Results from a Study with 2562 Patients
No full textInternational audienc
Organizing Global Supply Chains: Input-Output Linkages and Vertical Integration
No full textInternational audienceAbstract We study how the technological importance of inputs—measured by cost shares—is related to the decision to “make” or “buy” that input. Using detailed French international trade data and an instrumental variable approach based on self-constructed input–output tables, we show that multinationals vertically integrate technologically important inputs. A stylized incomplete contracting model with both ex-ante and ex-post inefficiencies explains why: Technologically more important inputs are “made” when transaction cost economics type forces overpower property rights type forces. However, additional results show that both types of forces are needed to explain the full patterns in the data
Purposeful Ecosystem Orchestration
No full textInternational audienceChapter 7 begins by setting out the nature and importance of corporate purpose. The power and effect of corporate purpose depend on its authenticity and way in which it is specified. Striking a balance between breadth and vision, and specificity and precision determines its relevance and impact. Authenticity involves living the corporate purpose and translating it effectively into corporate actions. It should not be preserved in aspic but instead evolve steadily over time to promote its relevance. The chapter suggests that it is not only the internal organization of a company that should be aligned with its purpose but so too should its external ecosystem. Ecosystems include other businesses, non-profit organizations, local communities, and governments. Ecosystem orchestration ‘redefines a stakeholder’s “stake” in the corporate purpose as a forward-looking opportunity to co-create value, instead of a backward-looking opportunity to capture value created by the corporation on its own.
A Survey on Mixed-Integer Programming Techniques in Bilevel Optimization
No full textInternational audienceBilevel optimization is a field of mathematical programming in which some variables are constrained to be the solution of another optimization problem. As a consequence, bilevel optimization is able to model hierarchical decision processes. This is appealing for modeling real-world problems, but it also makes the resulting optimization models hard to solve in theory and practice. The scientific interest in computational bilevel optimization increased a lot over the last decade and is still growing. Independent of whether the bilevel problem itself contains integer variables or not, many state-of-the-art solution approaches for bilevel optimization make use of techniques that originate from mixed-integer programming. These techniques include branch-and-bound methods, cutting planes and, thus, branch-and-cut approaches, or problemspecific decomposition methods. In this survey article, we review bilevel-tailored approaches that exploit these mixed-integer programming techniques to solve bilevel optimization problems. To this end, we first consider bilevel problems with convex or, in particular, linear lower-level problems. The discussed solution methods in this field stem from original works from the 1980's but, on the other hand, are still actively researched today. Second, we review modern algorithmic approaches to solve mixed-integer bilevel problems that contain integrality constraints in the lower level. Moreover, we also briefly discuss the area of mixed-integer nonlinear bilevel problems. Third, we devote some attention to more specific fields such as pricing or interdiction models that genuinely contain bilinear and thus nonconvex aspects. Finally, we sketch a list of open questions from the areas of algorithmic and computational bilevel optimization, which may lead to interesting future research that will further propel this fascinating and active field of research
Quality of life in SSc-ILD patients: Understanding the impact of the ILD and the needs of the SSc-ILD patients and their need for caregivers in France
No full textInternational audienceObjectives:The objectives of this study were to describe the impact of systemic sclerosis associated interstitial lung disease, on quality of life, to estimate the correlation between quality of life and severity of lung disease and to assess the impact of interstitial lung disease on caregivers.Methods:Seven investigators included systemic sclerosis associated interstitial lung disease patients from December 2019 to April 2020. Sociodemographics and clinical data were collected. Patients reported outcomes and questionnaires were used with 1 generic patients reported outcome (EQ-5D-5L), 1 specific PRO (Brief Interstitial Lung Disease) and 2 self-reported questionnaires on impact of SSc complications and impact on caregivers. The correlation between forced vital capacity and EQ-5D-5L score was estimated with a multivariate linear regression model adjusted on several covariates.Results:In all, 89 patients were included. 26.4% were males, mean age was 58.2 ± 14.5 years. Mean EQ-5D-5L score = 0.79 ± 0.22 (median = 0.85). Mean EQ-5D-5L visual analog scale score = 60.8 ± 20.4 (median = 61.5). Mean King’s Brief Interstitial Lung Disease score = 58.4 ± 12.7 (median = 58.0). After adjustment on covariates, a significant correlation between forced vital capacity and EQ-5D-5L score was found with an increase of 0.003 of the EQ-5D-5L score for a 1% increase of FVC (p = 0.0096). No significant correlation between forced vital capacity and the EQ-VAS and King’s Brief Interstitial Lung Disease score were found. The impact of SSc on other organs was significantly correlated with EQ- 5D-5L score, respectively, for the impact scores on the lung system (p = 0.0003), heart system (p = 0.0182), Raynaud’s syndrome (p = 0.0015), digestive system (p = 0.0032), joints/muscles (p = 0.0003), skin (p < 0.0001), kidney (p = 0.0052) and gastro-oesophageal reflux (p = 0.0063). Significant correlations between King’s Brief Interstitial Lung Disease score and lung system (p < 0.0001), heart system (p < 0.0001), digital ulcers (p = 0.058), digestive system (p < 0.0001), kidney (p = 0.0004), skin (p = 0.0499) and gastro-oesophageal reflux (p = 0.0033) scores were found 68.5% of patients reported their need for a caregiver to help them in their daily life activities.Conclusion:Our study highlighted the strong burden of systemic sclerosis associated interstitial lung disease` for patients, especially with an impact on quality of life, on other organs manifestations and need for caregivers in their daily life
Past the business case: reorienting corporate philanthropy research towards outcomes and impact
No full textInternational audienc
Métaphores en sciences de gestion. Évolutions et usages
No full textInternational audienceComment étudier l’évolution des métaphores et leur utilisation en sciences de gestion ? Si la généralisation de l’utilisation d’une métaphore conduit à transformer la métaphore « vive » en métaphore « morte », alors toute nouvelle métaphore n’est-elle pas condamnée à disparaître ? Ce dossier accueille cinq articles qui contribuent, chacun à leur manière, au débat en apportant des éclairages complémentaires et nuancés à la question initiale. Au-delà, ces contributions montrent que les métaphores ne servent pas uniquement à décrire le monde des organisations mais sont parfois un outil méthodologique de recherche
Human papillomavirus (HPV) vaccine coverage rates (VCRs) in France: A French claims data study
No full textInternational audienceBackground: The French Cancer Plan 2014-2019 had a target of 60% HPV vaccine coverage. The PAPILLON study investigated the annual age-specific vaccination initiation rates and cumulative partial and complete vaccination rates in France from 2017 to 2022. It also identified the factors associated with vaccination in different age groups and those associated with the type of completion of the vaccination scheme (partial vs full vaccination).Methods: For this publication, all females recorded in the French National Claims database who initiated HPV vaccination between 1 July 2007 and 31 December 2018 and were aged between 11 and 19 years at initiation were included. Annual HPV vaccination initiation rates were estimated in 11- to 14-year-old (target population) and 15- to 19-year-old females (catch-up). Cumulative vaccine coverage rates (VCRs) were estimated among those who were 15, 16, 20 and 21 years old. Partial vaccination was defined by dispensing of at least one dose of HPV vaccine by the pharmacy, while full vaccination was defined by two or three doses dispensed by a pharmacy over an 18-month period, according to current French recommendations based on the age at vaccination initiation.Results: Among the 465,629 females who initiated HPV vaccination in 2017 or 2018, the initiation rate increased from 7.7 to 11.1% in 11- to 14-year-old girls and from 4.5 to 6.5% in 15- to 19-year-old females. In 2017 and 2018, the cumulative VCRs for partial vaccination by age 15 were 28.2% and 32.8%, respectively, while by age 20, they were 41.6% and 38.8%. The cumulative VCRs for full vaccination were 15.6% and 18.6% by age 16, while they were 25.9 and 23.6% by age 20. HPV vaccination initiation and completion were strongly associated with the use of health services.Conclusion: Overall, the HPV VCR substantively increased between 2017 and 2018, which is positive evidence of the resumption of vaccination. Updates in 2022 should confirm these results