Outgoing mobility - 1st session

• Project title: The right to be forgotten and estimation of excess risk in the absence of disease-specific registry data: methodological approaches to support public health decision-making
• Host team: Institute of Statistics, Biostatistics, and Actuarial Sciences / Louvain Institute for Data Analysis and Modeling. Director: Catherine LEGRAND, Université catholique de Louvain, Belgium
• Mobility dates: July 3 to 8, 2023
• Key words: Cancer; Right to be forgotten; Relative survival; Registries; Cohorts
• Summary for the general public:

Over the past two decades, a great deal of work has been done in France, and to a lesser extent in Belgium, to facilitate access to insurance products for people with a perceived aggravated risk. This work has resulted in the adoption of the "right to be forgotten" in French (in 2016) and Belgian (in 2019) legislation. The basic idea behind this "right to be forgotten" is that a person who has had cancer has the right, 10 years after the end of the last therapeutic protocol, to no longer declare it when applying for outstanding balance insurance for the purchase of a home. On the basis of work carried out by statisticians, epidemiologists and doctors, this 10-year period has been (greatly) reduced for certain types of pathology. In France, it has also been extended to other types of pathology. Our partners in Belgium are currently working to extend the right to forget in Belgium, in order to (1) reach the same level as in France, (2) include other pathologies and (3) include other insurance products (in particular, insurance linked to professional loans or life annuities). This work relies mainly on the use of survival analysis techniques, and requires the use of follow-up data, both for cohorts suffering from the pathology under study, and for the general population (or ideally the general population excluding people suffering from the pathology under consideration). However, such data are often non-existent or incomplete in terms of adjustment covariates (data from population registers are generally only stratified by sex and age category).

Faced with this lack of appropriate data, innovative solutions need to be implemented. To this end, we have chosen to use cohort or registry data from other countries and "adjust" them to the specificities of the country of interest (France or Belgium). This methodological work is being carried out within the framework of a university thesis co-supervised by Belgium and France. Simulations are currently underway to test the two methodological approaches we are developing, according to different scenarios. One is based on the use of an excess mortality model correcting for the missing information in general population mortality tables, and the other on the use of a GAM model correcting for this lack of information.

This period of mobility enabled progress to be made in the course of the project, as all the contributors were present at the same time, with time dedicated to this Research work. It also provided an opportunity to present to the members of this Institute work carried out in the past, paving the way for that carried out as part of this collaboration.

• Project title: Study and data collection on malaria control interventions in Burkina Faso
• Host team: National Malaria Control Program
• Mobility dates: April 25 to June 30, 2022 and August 19 to September 30, 2022
• Keywords: Malaria; surveillance; interventions; Burkina Faso
• Summary for the general public:

Researching the link between malaria and the interventions put in place to tackle it, with the aim of optimizing them, is a key step in the fight against malaria. We are interested in this link and propose to evaluate the performance of interventions and control strategies, and also to propose if necessary a reorganization or redeployment of interventions in the appropriate time and space for an efficient result. Knowing the details and implementation methods of these interventions is therefore essential to address this work and support the malaria control strategy in Burkina Faso.

Our first task at the PNLP was therefore to collect data on interventions implemented to combat malaria. These interventions include the distribution of impregnated mosquito nets (pregnant women, children under 5 and the general population), seasonal chemoprevention, indoor residual spraying, intermittent preventive treatments, community health agents and rapid screening tests.

We then verified the data and corrected any outliers. Finally, we will use this good quality data to Research the link between malaria and interventions, and possibly propose a new strategy for implementing these interventions in collaboration with the PNLP. This work will therefore lead to the updating of the epidemiological malaria facies in Burkina Faso, and also to a stratification of the country into homogeneous zones to be strategically targeted when implementing control interventions.

• Project title: Evaluation médico-économique de la prise en charge des patients hépatite B chronique dans le cadre de la cohorte Sen-B à Dakar (ECO-SenB)
• Host team: Department of Infectious and Tropical Diseases, Fann Hospital (SMIT, Pr Moussa Seydi)
• Mobility dates: February 4 to 15, 2024
• Keywords: economic evaluation; cost-effectiveness; chronic hepatitis B; Senegal
• Summary for the general public:

I carried out a ten-day mission in Senegal as part of my post-doctorate (IRD) carried out at SESSTIM on the evaluation of the efficiency and equity of viral hepatitis management models in sub-Saharan Africa.
As part of this assignment, I mainly worked in the Infectious and Tropical Diseases Department (SMIT) at Fann Hospital with the "Sen-B" research cohort team. Since 2019, the Sen-B cohort has recruited and followed nearly 1,000 patients with chronic hepatitis B virus (HBV) infection. It is the largest cohort of people living with chronic HBV infection (PLHIV) in sub-Saharan Africa.
The main objective of my assignment was to gather the data required to carry out a medico-economic evaluation of the cohort's proposed management of PLHIV. Using mathematical modelling tools, this evaluation enables us to project into the future and estimate the effectiveness (in terms of life-years gained, for example) and cost (for the healthcare system) of the cohort's proposed management of PLHV. These are very important data for public decision-makers and international funding agencies.
The medico-economic evaluation is based on simulating the fate of PLHIV, with and without medical follow-up. It is therefore first necessary to model their evolution by defining several possible states of health through which PLHIV may pass. A major part of my mission was to gain a clear understanding of the cohort's proposed follow-up, the indications for starting treatment and the possible evolution of patients, with and without treatment. These discussions led to the development of a clinical model specific to the cohort's HBV follow-up (see below).

The other part of the medico-economic analysis was based on a study of the costs associated with each health state in the model. The costs of biological examinations were collected from the SMIT and CRCF laboratories, the costs of consultations and imaging procedures were evaluated after interviews with the cohort staff, and the costs of medication were obtained from the Fann Hospital central pharmacy and several private pharmacies. Finally, I took advantage of this mission to meet Fatou Nguirane, president of the PVVHB association "Saafara Hépatites", to discuss future collaborations.
My mission ended with a meeting with the Research team to (i) present the progress and next steps of the cost-effectiveness analysis and (2) validate the plan for the quality of life analyses around two draft articles.