Theodoros Evrenoglou
Thesis defended in 2022

Theodoros Evrenoglou

Dealing with sparse data in network meta-analysis

Supervisor: Anna Chaimani

Thesis manuscript

Jules Grégory
Thesis defended in 2022

Jules Gregory

Evaluation methods in interventional radiology: the example of the intra-arterial hepatic chemoembolization of hepatocellular carcinomas

Supervisor : Isabelle Boutron

Arthur James
Thesis defended in 2022

Arthur James

Development of a method to identifying consensual criteria for long-term evaluation : the example of severe trauma

Supervisors : Philippe Ravaud and Viet-Thi Tran

First of all, during a systematic review we identify the themes currently favored by authors. Then we will conduct a survey of severely traumatized patients to identify the areas that are critical to them. Finally, we will achieve a consensus between patients and clinicians that will define what elements must be primarily described to assess a serious long-term trauma.

Theodora Oikonomidi
Thesis defended in 2021

Theodora Oikonomidi

Exploring opportunities for the personalization of digital behavior change interventions

Supervisors : Philippe Ravaud and Viet-Thi Tran

We will identify ways to optimize digital behavior change interventions. We will explore patient perceptions regarding the intrusiveness and acceptability of digital tools and we will examine different behavioral frameworks for the personalization of digital behavior change interventions, producing relevant recommendations for intervention development.

Ketevan Glonti
Thesis defended in 2021

Ketevan Glonti

Peer-review content and communication process in biomedical journals

Supervisors : Darko Hren, Erik Cobo and Isabelle Boutron

A number of problems have emerged in the peer review process used by scientific journals across most disciplines.

This project investigates peer review content and communication process in biomedical journals

Mona Ghannad
Thesis defended in 2021

Monna Ghannad

An alternative approach for planning the research of innovative medical tests

Supervisors : Patrick Bossuyt and Isabelle Boutron

Accurate presentation of the results of clinical research is the cornerstone of the dissemination of the results and their implementation in clinical practice. The aim of this project is to identify, develop and evaluate strategies for preventing, eliminating, or limiting “spin” in clinical research. “Spin” can be defined as specific reporting that could distort the interpretation of results and mislead readers. The most disturbing form would be to suggest that health care interventions are beneficial, despite the absence of convincing evidence. Such “spin” has been documented in the reporting of RCTs, diagnostic accuracy studies, systematic reviews, and other forms of evaluation.

Lorenzo Bertizzolo
Thesis defended in 2021

Lorenzo Bertizzolo

Improving the assessment of Risk of Bias in Systematic Reviews

Supervisors : Agnès Dechartres and Patrick Bossuyt

Evaluating the Risk of Bias (RoB) of a study is a very important passage while conducting a Systematic Review and evaluating research. The RoB is the main determinant of the internal validity of study, which is one of the most important aspects of it. The validity of a study represents how well it reflects the reality it is trying to describe. This project aims to evaluate the reproducibility of the RoB assessment, explore its importance on the results of studies and propose ways to improve the understanding, use and dissemination of “measuring tools” for the Risk of Bias assessment.

Linda Nyanchoka
Thesis defended in 2021

Linda Nyanchoka

Methods of identifying gaps in clinical research

Supervisors : Raphaël Porcher and Catrin Tudur Smith

A research gap is defined as a topic area which missing or insufficient information limits the ability to reach a conclusion for a question. Identification of research gaps has the potential to inform the design and conduct of research, evidence-based decision-making, health policies, and practice. Audiences including the public, patients, researchers, clinicians, advocacy groups, and funders can benefit from understanding the current status of research and research gaps in a field. This project aims to identify, describe and classify methods to identify and display gaps in clinical research and develop methodological guidance.

Astrid Chevance
Thesis defended in 2020

Astrid Chevance

New methods for the development of Core Outcome Set (COS): proof of concept with the example of Major Depressive Disorder

Supervisors : Philippe Ravaud and Viet-Thi Tran

We propose methods for COS development, allowing the implementation of patient’s, carer’s, clinician’s, and researcher’s preferences on outcomes, based on international surveys, taking the example of Major Depressive Disorder (unipolar) in adults (18-65 years old). Different degrees of stakeholder’s involvement will be defined for each stage of the research process. Finally we will be able to propose a ready-to-use COS for depression and useful methods for developing COS in other disease.

Tat-Thang Vo
Thesis defended in 2020

Tat-Thang Vo

Novel approach for meta-analysis: a causality framework

Supervisors : Catrin Tudur Smith and Raphaël Porcher

Standard methodology for meta-analysis is focusing too much on deriving a summary treatment effect but remains implicit about the patient population for which this summary result is described. We aims at developing a new meta-analysis technique for RCTs, which will estimate the treatment effect for each of the populations in the considered trials by combining the information across all studies.

Van Nguyen
Thesis defended in 2020

Van Nguyen

Impact of mobilising collective intelligence in clinical research planning

Supervisors : Isabelle Boutron and Bridget Young

A new method is needed to tackle the challenges that clinical research planning is facing. We investigate whether and how collective intelligence is applied to transform clinical research planning.

Alice Biggane
Thesis defended in 2020

Alice Biggane

Methods for including participants in core outcome set development

Supervisors : Paula Williamson and Philippe Ravaud

Participants such as health professionals and patients are increasingly contributing to the development of core outcome sets. However, the best methods for facilitating this participation remains unknown. Thus, this mixed- methods project aims to provide guidance on the methods used to ensure participation is as meaningful as possible.

Youri Yordanov
Thesis defended in 2019

Youri Yordanov

Avoidable Waste of research in clinical trials

Supervisors : Philippe Ravaud and Agnès Dechartres

Thesis of Youri Yordanov

Jean-David Zeitoun
Thesis defended in 2018

Jean-David Zeitoun

Innovation and pharmaceutical development

Supervisor : Philippe Ravaud

Post-marketing trials are paramount for enhancing evidence about novel medicines once they are used at a massive scale

We systematically studied all post-marketing trials conduceted at a global scale for a consistent sample of novel medicines approved by the two leading regulators

We found extreme variations in the way medicines were studied after approval.

Anthony Chauvin
Thesis defended in 2018

Anthony Chauvin

Medication adherence among patients taking long-term treatments

Supervisors : Isabelle Boutron and David Moher

Thesis of Anthony Chauvin

Development and evaluation of interventions to improve the peer-review process in biomedical research

Stéphanie Sidorkiewicz
Thesis defended in 2017

Stéphanie Sidorkiewicz

Medication adherence among patients taking long-term treatments

Supervisors : Philippe Ravaud and Viet-Thi Tran

Thesis of Stéphanie Sidorkiewicz

This doctoral thesis focused on medication adherence among patients with one or several chronic conditions and taking multiple medications.
The first PhD project was the development of an instrument to assess medication adherence, with a “drug by drug” perspective. Validity and reliability of the tool were tested among 243 patients in France. The two other projects focused on the discordance between patients’ and physicians’ points of view about medication importance and on the estimation of the threshold for unacceptable risk of non-adherence according to 544 physicians for the most prescribed drugs in France. The results suggested a huge variation in physicians’ estimations according to the drug of interest.

Ignacio Atal
Thesis defended in 2017

Ignacio Atal

World maping of clinical trials

Supervisor : Raphaël Porcher and Ludovic Trinquart

Thesis of Ignacio Atal

In this thesis we mapped registered clinical trials at a macro-level, i.e. we analyzed what clinical research is undertaken worldwide, where it is conducted, which diseases are studied, and who is supporting it.
We highlighted major gaps in the effort of health research as compared to health needs, and the influence of different sponsors in the globalization of clinical research.

Lee Aymar Ndounga Diakou
Thesis defended in 2017

Lee Aymar Ndounga

Implementation of Results of Randomized Trials in Sub-Saharan Africa

Supervisor : Isabelle Boutron

Thesis of Lee Aymar Ndoundga

We found that SSA RCTs investigate locally high burdened diseases, however these trials are frequently led by high income countries.
Moreover, SSA RCTs at high risk of biais could be changed in trials at low risk of bias with simple methodological adjustments of minor cost, and the completeness of the intervention description could be improved with the adherence to CONSORT guidelines.

Romana Haneef
Thesis defended in 2017

Romana Haneef

Dissemination and communication of clinical research evaluating treatments

Supervisor : Isabelle Boutron

Thesis of Romana Haneef

This thesis assessed the prevalence of spin in Google Health news, classified different strategies of spin and identified that factors related to publication process were associated with high dissemination through online media. This work highlighted the importance of spin in mass media and provided a tool (classification of spin) to improve the dissemination and communication of research results.

Alexandre Vivot
Thesis defended in 2017

Alexandre Vivot

Medicine in Oncology: Translation of Genetic Biomarkers Discoveries to the Clinic

Supervisor : Raphaël Porcher

Thesis of Alexandre Vivot

We analyzed all the FDA-approved drugs with a pharmacogenetic biomarker in their label and showed that (1) predictive biomarkers in the label of drugs is restricted in large part to oncology; (2) the level of evidence for clinical utility is often unknown because studies are restricted to the subgroup of biomarker-positive patients from the initial stages of the drug development; (3) there are very important variations between drugs in the use of enriched trials and in testing of the drug in several indications or with several predictive biomarker; and finally (4) that only one third of the anti-cancer drugs approved by the FDA between 2000 and 2015 have meaningful clinical benefit.

Michaïl Kovanis
Thesis defended in 2017

Michail Kovanis

Modelling the complex system of scientific publication

Supervisors : Raphaël Porcher and Ludovic Trinquart

Thesis of Michail Kovanis

Phrase: In my PhD thesis, I modeled the macroscopic behavior of the scientific publication and peer-review systems, and I showed that the scientific community can collectively meet the annual demand for peer review, however, only 20% of researchers have been performing 69%-94% of reviews. Moreover, my results indicated that peer-review systems which allow sharing of past reviews of rejected manuscripts between journals showed important advantages, such as improved peer-review efficiency, less reviewer effort and better scientific dissemination.

Guillaume Lonjon
Thesis defended in 2017

Guillaume Lonjon

Use of propensity score in observational studies in surgery. Description, comparison, bias

Supervisor : Isabelle Boutron

Thesis of Guillaume Lonjon

In this project, I aimed to 1) compare treatment effect estimates from non-randomized studies with PS analysis and RCTs and 2) describe and assess the reporting and potential bias of PS analysis used in a sample of published observational studies assessing surgical procedures.

Céline Buffel du Vaure
Thesis defended in 2016

Evidence-Based-Medicine limits for management of multimorbidity in General Practice

Supervisor : Isabelle Boutron

Perrine Crequit
Thesis defended in 2016

Perrine Crequit

Network meta-analysis and oncolog

Supervisor : Philippe Ravaud and Ludovic Trinquart

Thesis of Perrine Créquit

Systematic reviews are essential tools to synthesize available evidence for therapeutic evaluation. Multiple treatments are now frequently available for a given condition. Patients and physicians want to know which one is the best among all treatments. Thus we need to retrieve and synthesize all available evidence across all treatments and furthermore to maintain it updated when new evidence and new treatments become available.

Our objective was to evaluate the limits of the current ecosystem of evidence synthesis and to develop an alternative methodology.

Anne Rousseau
Thesis defended in 2016

Anne Rousseau

Immediate Postpartum hemorrhage severe. Analysis of environmental and organizational factors

Supervisor : Philippe Ravaud and Patrick Rozenberg

Thesis of Anne Rousseau

The objective of this PhD thesis was to develop and validate a methodology with dynamic case-vignette to study discrepancies with good practices and to assess determinants related to the organization of care and / or caregivers in postpartum hemorhage management.

Amélie Yavchitz
Thesis defended in 2015

Amelie Yavchitz

Dissemination of scientific findings from randomized controlled trials and systematic reviewss

Supervisor : Isabelle Boutron

Thesis of Amélie Yavchitz

An accurate and complete presentation by authors of all the important information in report of randomized controlled trial (RCT) and systematic reviews (SR) is essential to allow a critical appraisal of the study by readers. Spin was defined as a specific way of reporting, deliberate or not, that can lead to a “beautification” of the data. We showed that 1) spin are disseminated in press releases and news and they are associated with an overestimation of the beneficial effect of treatment, 2) the addition of a limitation section in abstract of systematic reviews and meta-analysis does not impact the confidence in the study results by readers. Finally, we developed a classification scheme of spin in systematic reviews and meta-analyzes, and we ranked spin in abstract according to their perceived severity

Clémence Palazzo
Thesis defended in 2016

Evaluation and improvement of qualitative compliance in rehabilitation

Supervisor : Philippe Ravaud and Serge Poiraudeau

Clarisse Dibao-Dina
Thesis defended in 2015

Unbalanced randomization and ambivalence clause

Supervisor : Bruno Giraudeau

Cécile Pino
Thesis defended in 2015

Educational interventions: Applicability of results and effectiveness of new forms of intervention

Supervisors : Philippe Ravaud and Isabelle Boutron

Viet-Thi Tran
Thesis defended in 2015

Viet-Thi Tran

Development of tools to measure treatment burden in patients with multiple chronic diseases

Supervisor : Philippe Ravaud

Thesis of Viet-Thi Tran

As chronic diseases are becoming more prevalent, their management strategies are becoming more complicated. Patients are feeling increasingly burdened by their treatments. This burden of treatment represents the “work of being a patient”. It affects treatment adherence, quality of life and outcomes. In order to take into account this burden, clinicians and researchers needed tools to assess it.

Aïda Bafeta
Thesis defended in 2015

Epidemiology and methodology of meta-analyzes network

Supervisor : Philippe Ravaud

Thesis of Aïda Bafeta

Network meta-analyses are primarily meta-analyses; they are probably subject to the same types of bias and should therefore be performed according to the explicit and rigorous methods used in systematic reviews. We assessed whether network meta-analyses follow the key methodological recommendations for reporting and conduct of systematic reviews, and how the results of network meta-analyses are reported.

Bénédicte Sautenet
Thesis defended in 2015

Assessment of outcomes heterogeneity in nephrology randomized trials: meta-epidemiological study

Supervisor : Bruno Giraudeau