Benjamin Castagné

Marie Viprey

Julie Martin

Anne-Marie Schott

Michel Cucherat

Martin Soubrier

´ Benjamin Castagne
email: bcastagne@chu-clermontferrand.fr

Cardiovascular safety of tocilizumab: A systematic review and network meta-analysis

Introduction

Rheumatoid Arthritis (RA) is one of the most frequent chronic inflammatory rheumatism (CIR), characterized by chronic inflammation of joints, particularly hands and feet. The management of RA has been revolutionized with the development of biological disease-modifying antirheumatic drugs (bDMARD) [START_REF] Smolen | EULAR recommendations for the management of rheumatoid arthritis with synthetic and biological disease-modifying antirheumatic drugs: 2016 update[END_REF][START_REF] Guillemin | Prevalence of rheumatoid arthritis in France: 2001[END_REF]. Mortality is increased in RA, especially due to cardiovascular diseases (CVD) [START_REF] Aviña-Zubieta | Risk of cardiovascular mortality in patients with rheumatoid arthritis: a meta-analysis of observational studies[END_REF][START_REF] Ogdie | Risk of major cardiovascular events in patients with psoriatic arthritis, psoriasis and rheumatoid arthritis: a population-based cohort study[END_REF]. In a Danish population based study, the risk of CVD was similar between RA and diabetes (RR 1.7 95% CI 1.5 to 6.9 vs RR 1.7 95% CI 1.6 to 1.8, respectively, p = 0.64) [START_REF] Lindhardsen | The risk of myocardial infarction in rheumatoid arthritis and diabetes mellitus: a Danish nationwide cohort study[END_REF]. The cardiovascular risk seems to be linked with the disease's activity. In a recent study, Arts & al showed that low disease activity (DAS28 �3.2) was associated with a reduced risk of CVD (HR 0.65 95% CI 0.43 to 0.99) compared with moderate or high disease activity (DAS28 >3.2) [START_REF] Arts | The effect of disease duration and disease activity on the risk of cardiovascular disease in rheumatoid arthritis patients[END_REF].

The release of inflammatory cytokines (IL6, IL1, TNF alpha) leads to a decrease of total cholesterol (CT), especially HDL-cholesterol (HDL-C) [START_REF] Zo ¨ller | Risk of subsequent ischemic and hemorrhagic stroke in patients hospitalized for immune-mediated diseases: a nationwide follow-up study from Sweden[END_REF][START_REF] Charles-Schoeman | Effects of tofacitinib and other DMARDs on lipid profiles in rheumatoid arthritis: implications for the rheumatologist[END_REF]. Furthermore, the anti-atherogenic function of HDL-cholesterol become pro-atherogenic because of a linkage with inflammatory proteins like SAA [START_REF] Charles-Schoeman | Effects of tofacitinib and other DMARDs on lipid profiles in rheumatoid arthritis: implications for the rheumatologist[END_REF]. In the recent recommendations of the European Ligue Against Rheumatism (EULAR), CVD risk assessment is recommended for all patients with RA at least once every 5 years [START_REF] Agca | EULAR recommendations for cardiovascular disease risk management in patients with rheumatoid arthritis and other forms of inflammatory joint disorders: 2015/2016 update[END_REF].

Tocilizumab (TCZ) is a bDMARD which blockades the IL-6 receptor and has demonstrated its efficacy to control the disease activity in a phase III double-blinded randomized controlled trial (RCT): the OPTION study [START_REF] Smolen | Effect of interleukin-6 receptor inhibition with tocilizumab in patients with rheumatoid arthritis (OPTION study): a double-blind, placebo-controlled, randomised trial[END_REF]. However, RCT and other studies showed that TCZ was associated with an increased cholesterol level [START_REF] Smolen | Effect of interleukin-6 receptor inhibition with tocilizumab in patients with rheumatoid arthritis (OPTION study): a double-blind, placebo-controlled, randomised trial[END_REF][START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF]. This increase was also estimated superior compared to adalimumab (ADA) in a post-hoc analysis of the ADACTA trial [START_REF] Gabay | Comparison of lipid and lipid-associated cardiovascular risk marker changes after treatment with tocilizumab or adalimumab in patients with rheumatoid arthritis[END_REF]. TCZ interacts with CYP450 which is also implicated in atorvastatin metabolism [START_REF] Bellosta | Statin drug interactions and related adverse reactions: an update[END_REF]. Therefore, it has been used with caution in patients with high cardiovascular risk, particularly those with dyslipidemia. Recent studies showed reassuring data concerning major adverse cardiovascular events (MACE) with TCZ compared to other bDMARD [START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF][START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF][START_REF] Curtis | Tocilizumab in rheumatoid arthritis: a case study of safety evaluations of a large postmarketing data set from multiple data sources[END_REF][START_REF] Gottenberg | Similar Rates of Death, Serious Infections, Cancers, Major Cardiovascular Events in Patients Treated with Abatacept, Rituximab and Tocilizumab: Long-Term Registry Data in 4498 Patients with Rheumatoid Arthritis[END_REF]. Two studies conducted in American databases underscored significant decrease in cardiovascular events with TCZ [START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF]. In Zhang & al. study, TCZ reduced the risk of myocardial infarction (MI) significantly more than abatacept (ABA) (HR 0.64 95% CI 0.41 to 0.99) [START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF]. Kim & al. found better cardiovascular outcomes with TCZ comparing to TNF inhibitors (TNFi) (HR 0.68 95% CI 0.49 to 0.94) [START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF]. Furthermore, TCZ decreases inflammatory proteins like SAA, and may restore the anti-atherogenic function of HDL-C.

Given these controversial results, we aimed to assess the cardiovascular safety of tocilizumab in rheumatoid arthritis compared to other bDMARD using a network meta-analysis (NMA).

Materials and methods

This systematic review with meta-analysis was conducted and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement (PRISMA) guidelines (S1 File) [START_REF] Moher | Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement[END_REF]. Our protocol was recorded on PROSPERO under the registration number CRD42018097180.

Literature search

This systematic review was performed by searching in PubMed/Medline, Science Direct, and Web of Science databases, and in Cochrane and Wiley Online libraries. We also searched abstracts in the American College of Rheumatology (ACR) and European Ligue Against Rheumatism (EULAR) annual meetings databases, from January 2003 until May 2018. The search equations are available in supporting information (S2 File).

Eligibility criteria

Our eligibility criteria for qualitative analysis were: RCT or observational (cohort only) studies, wrote in French or in English, assessing cardiovascular outcomes among rheumatoid arthritis patients treated by TCZ and/or ABA and/or rituximab (RTX) and/or TNFi.

Study selection

Studies were selected on the basis of their titles and abstracts, then on their full text, by two independent reviewers (BC, JM). Disagreements were resolved through discussion with a third reviewer (MV), when necessary.

Data extraction and quality assessment

Two reviewers (BC and JM) assessed independently the quality of selected studies using the Cochrane Risk Of Bias tool (RoB 2.0) [START_REF] Higgins | Appraising the risk of bias in randomized trials using the Cochrane Risk of Bias Tool[END_REF] for randomized studies and the Cochrane Risk Of Bias In Non-randomized Studies-of Interventions (ROBINS-I tool) [START_REF] Sterne | ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions[END_REF] for non-randomized. The two reviewers (BC and JM) also performed data extraction independently using a predetermined form. If necessary, disagreements were resolved by the third reviewer (MV). We extracted from each study: authors and publication year, country, bDMARD used in the study, number of previous bDMARD and previous csDMARD, number of patients, patientyear, follow-up period (year), number of MACE (major adverse cardiovascular events), myocardial infarction (MI), stroke, cardiac heart failure (CHF) and peripheral artery disease (PAD),

Outcomes measures

The composite primary outcome was the rate of MACE which included stroke, MI, CHF and PAD (obliterating arteriopathy of the limbs, kidney and mesenteric artery diseases and aortic diseases. The secondary outcomes were rates of each cardiovascular event).

Data analysis

A frequentist network meta-analysis based on a random effects model [START_REF] Senn | Trying to be precise about vagueness[END_REF] was conducted for all outcomes to compute relative risk (RR) and their 95% confidence interval (95%CI). NMA allows to synthesize information from numerous studies addressing the same outcomes but involving different interventions [START_REF] Dias | Evidence synthesis for decision making 1: introduction[END_REF][START_REF] Dias | Evidence synthesis for decision making 4: inconsistency in networks of evidence based on randomized controlled trials[END_REF]. NMA combines direct and indirect evidence across a network of studies into a single effect size. Forest plots were used to represent the quantitative results. For pairwise comparison, statistical heterogeneity between studies was assessed by the Cochran's Q test (p<0.05 for significativity) and the I 2 statistic (<25%: low heterogeneity, 25-50%: moderate, 50-75%: high and >75%: very high). All analyses were performed using R (netmeta package version 0.9-5 for treatment comparison, meta package version 4.8-2, R Language and Environment for Statistical Computing, Vienna, Austria) [START_REF] Ru ¨cker | Network meta-analysis, electrical networks and graph theory[END_REF][START_REF] Ru ¨cker | Netmeta. Network meta-analysis using frequentist methods[END_REF]. A subgroup analysis was performed, including RCTs only and cohort studies only.

Results

Literature search results and studies characteristics

After duplicates removal, 10 454 articles were found using PubMed/Medline, Science direct, Web of science, Cochrane library databases and ACR and EULAR conference abstracts. Of the 10 454 identified records, 10 319 were excluded at title/abstract level, leaving 135 full-text examined. Of these, we selected 29 studies, 27 original articles and two conference abstracts [START_REF] Gottenberg | Similar Rates of Death, Serious Infections, Cancers, Major Cardiovascular Events in Patients Treated with Abatacept, Rituximab and Tocilizumab: Long-Term Registry Data in 4498 Patients with Rheumatoid Arthritis[END_REF][START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF] for qualitative analysis (Fig 1). 106 articles did not meet the inclusion criteria for the following reasons: one was a case-control study, 55 were not controlled studies, 44 did not have clinical outcomes (biological or imaging), five because the studied population was already included, and one because the full-test could not be accessed.

Of the 29 studies included in the qualitative analysis, 13 studies were conducted in North America [START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF][START_REF] Curtis | Tocilizumab in rheumatoid arthritis: a case study of safety evaluations of a large postmarketing data set from multiple data sources[END_REF][START_REF] Al-Aly | Tumor necrosis factor-α blockade, cardiovascular outcomes, and survival in rheumatoid arthritis[END_REF][START_REF] Emery | Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naive with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab's Efficacy in MTX iNadequate rEsponders (SERENE))[END_REF][START_REF] Harrold | Comparative effectiveness and safety of rituximab versus subsequent anti-tumor necrosis factor therapy in patients with rheumatoid arthritis with prior exposure to anti-tumor necrosis factor therapies in the United States Corrona registry[END_REF][START_REF] Jin | Comparative Cardiovascular Safety of Abatacept and Tumor Necrosis Factor Inhibitors in Rheumatoid Arthritis Patients with and Without Cardiovascular Disease: A Population-Based Cohort Study[END_REF][START_REF] Keystone | Safety and Efficacy of Subcutaneous Golimumab in Patients with Active Rheumatoid Arthritis despite Methotrexate Therapy: Final 5-year Results of the GO-FORWARD Trial[END_REF][START_REF] Kim | No difference in cardiovascular risk of tocilizumab versus abatacept for rheumatoid arthritis: A multi-database cohort study[END_REF][START_REF] Westhovens | The safety of infliximab, combined with background treatments, among patients with rheumatoid arthritis and various comorbidities: a large, randomized, placebo-controlled trial[END_REF][START_REF] Weisman | A placebo-controlled, randomized, double-blinded study evaluating the safety of etanercept in patients with rheumatoid arthritis and concomitant comorbid diseases[END_REF], 16 in Europe [START_REF] Smolen | Effect of interleukin-6 receptor inhibition with tocilizumab in patients with rheumatoid arthritis (OPTION study): a double-blind, placebo-controlled, randomised trial[END_REF][START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Curtis | Tocilizumab in rheumatoid arthritis: a case study of safety evaluations of a large postmarketing data set from multiple data sources[END_REF][START_REF] Gottenberg | Similar Rates of Death, Serious Infections, Cancers, Major Cardiovascular Events in Patients Treated with Abatacept, Rituximab and Tocilizumab: Long-Term Registry Data in 4498 Patients with Rheumatoid Arthritis[END_REF][START_REF] Emery | Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naive with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab's Efficacy in MTX iNadequate rEsponders (SERENE))[END_REF][START_REF] Westhovens | The safety of infliximab, combined with background treatments, among patients with rheumatoid arthritis and various comorbidities: a large, randomized, placebo-controlled trial[END_REF][START_REF] Burmester | Tocilizumab combination therapy or monotherapy or methotrexate monotherapy in methotrexate-naive patients with early rheumatoid arthritis: 2-year clinical and radiographic results from the randomised, placebo-controlled FUNCTION trial[END_REF][START_REF] Ca ´rdenas | Real-world cost-effectiveness of infliximab, etanercept and adalimumab in rheumatoid arthritis patients[END_REF][38][39][40][41][42][43][44][45], five in Asia [START_REF] Curtis | Tocilizumab in rheumatoid arthritis: a case study of safety evaluations of a large postmarketing data set from multiple data sources[END_REF][START_REF] Keystone | Safety and Efficacy of Subcutaneous Golimumab in Patients with Active Rheumatoid Arthritis despite Methotrexate Therapy: Final 5-year Results of the GO-FORWARD Trial[END_REF][46][47][48], four in South America [START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Curtis | Tocilizumab in rheumatoid arthritis: a case study of safety evaluations of a large postmarketing data set from multiple data sources[END_REF][START_REF] Westhovens | The safety of infliximab, combined with background treatments, among patients with rheumatoid arthritis and various comorbidities: a large, randomized, placebo-controlled trial[END_REF]38] and two in Australia [START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Keystone | Safety and Efficacy of Subcutaneous Golimumab in Patients with Active Rheumatoid Arthritis despite Methotrexate Therapy: Final 5-year Results of the GO-FORWARD Trial[END_REF]. Study characteristics are available in Table 1. 16/29 studies were RCT [START_REF] Smolen | Effect of interleukin-6 receptor inhibition with tocilizumab in patients with rheumatoid arthritis (OPTION study): a double-blind, placebo-controlled, randomised trial[END_REF][START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF][START_REF] Emery | Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naive with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab's Efficacy in MTX iNadequate rEsponders (SERENE))[END_REF][START_REF] Keystone | Safety and Efficacy of Subcutaneous Golimumab in Patients with Active Rheumatoid Arthritis despite Methotrexate Therapy: Final 5-year Results of the GO-FORWARD Trial[END_REF][START_REF] Westhovens | The safety of infliximab, combined with background treatments, among patients with rheumatoid arthritis and various comorbidities: a large, randomized, placebo-controlled trial[END_REF][START_REF] Weisman | A placebo-controlled, randomized, double-blinded study evaluating the safety of etanercept in patients with rheumatoid arthritis and concomitant comorbid diseases[END_REF][START_REF] Burmester | Tocilizumab combination therapy or monotherapy or methotrexate monotherapy in methotrexate-naive patients with early rheumatoid arthritis: 2-year clinical and radiographic results from the randomised, placebo-controlled FUNCTION trial[END_REF]39,[41][42][43][44][45][46],48]and 13/29 were cohort studies [START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF][START_REF] Curtis | Tocilizumab in rheumatoid arthritis: a case study of safety evaluations of a large postmarketing data set from multiple data sources[END_REF][START_REF] Gottenberg | Similar Rates of Death, Serious Infections, Cancers, Major Cardiovascular Events in Patients Treated with Abatacept, Rituximab and Tocilizumab: Long-Term Registry Data in 4498 Patients with Rheumatoid Arthritis[END_REF][START_REF] Al-Aly | Tumor necrosis factor-α blockade, cardiovascular outcomes, and survival in rheumatoid arthritis[END_REF][START_REF] Harrold | Comparative effectiveness and safety of rituximab versus subsequent anti-tumor necrosis factor therapy in patients with rheumatoid arthritis with prior exposure to anti-tumor necrosis factor therapies in the United States Corrona registry[END_REF][START_REF] Jin | Comparative Cardiovascular Safety of Abatacept and Tumor Necrosis Factor Inhibitors in Rheumatoid Arthritis Patients with and Without Cardiovascular Disease: A Population-Based Cohort Study[END_REF][START_REF] Kim | No difference in cardiovascular risk of tocilizumab versus abatacept for rheumatoid arthritis: A multi-database cohort study[END_REF][START_REF] Ca ´rdenas | Real-world cost-effectiveness of infliximab, etanercept and adalimumab in rheumatoid arthritis patients[END_REF]38,40,47,49]. Of the 13 cohort studies, five [START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF][START_REF] Curtis | Tocilizumab in rheumatoid arthritis: a case study of safety evaluations of a large postmarketing data set from multiple data sources[END_REF][START_REF] Jin | Comparative Cardiovascular Safety of Abatacept and Tumor Necrosis Factor Inhibitors in Rheumatoid Arthritis Patients with and Without Cardiovascular Disease: A Population-Based Cohort Study[END_REF][START_REF] Kim | No difference in cardiovascular risk of tocilizumab versus abatacept for rheumatoid arthritis: A multi-database cohort study[END_REF] were performed using national health care databases and four [START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF][START_REF] Jin | Comparative Cardiovascular Safety of Abatacept and Tumor Necrosis Factor Inhibitors in Rheumatoid Arthritis Patients with and Without Cardiovascular Disease: A Population-Based Cohort Study[END_REF][START_REF] Kim | No difference in cardiovascular risk of tocilizumab versus abatacept for rheumatoid arthritis: A multi-database cohort study[END_REF] were propensity matched. Of the 16 RCT, four were open-label trials [START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF]41,43,46], the others were double-blinded.

We identify two major concerns due to cofounding in two cohort studies [40,49], because of the absence of multivariate analysis. The other potential bias was selective reporting due to the absence of online recorded protocol for 8 studies. Detailed bias assessment is reported in Table 2.

For quantitative analysis, analyzable data for NMA were available in only 19 studies for MACE outcome [START_REF] Smolen | Effect of interleukin-6 receptor inhibition with tocilizumab in patients with rheumatoid arthritis (OPTION study): a double-blind, placebo-controlled, randomised trial[END_REF][START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF][START_REF] Al-Aly | Tumor necrosis factor-α blockade, cardiovascular outcomes, and survival in rheumatoid arthritis[END_REF][START_REF] Emery | Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naive with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab's Efficacy in MTX iNadequate rEsponders (SERENE))[END_REF][START_REF] Harrold | Comparative effectiveness and safety of rituximab versus subsequent anti-tumor necrosis factor therapy in patients with rheumatoid arthritis with prior exposure to anti-tumor necrosis factor therapies in the United States Corrona registry[END_REF][START_REF] Keystone | Safety and Efficacy of Subcutaneous Golimumab in Patients with Active Rheumatoid Arthritis despite Methotrexate Therapy: Final 5-year Results of the GO-FORWARD Trial[END_REF][START_REF] Kim | No difference in cardiovascular risk of tocilizumab versus abatacept for rheumatoid arthritis: A multi-database cohort study[END_REF][START_REF] Westhovens | The safety of infliximab, combined with background treatments, among patients with rheumatoid arthritis and various comorbidities: a large, randomized, placebo-controlled trial[END_REF][38][39][40][42][43][44]46,48,49], eight for MI [START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Zhang | Comparative effects of biologics on cardiovascular risk among older patients with rheumatoid arthritis[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF][START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF][START_REF] Keystone | Safety and Efficacy of Subcutaneous Golimumab in Patients with Active Rheumatoid Arthritis despite Methotrexate Therapy: Final 5-year Results of the GO-FORWARD Trial[END_REF][START_REF] Westhovens | The safety of infliximab, combined with background treatments, among patients with rheumatoid arthritis and various comorbidities: a large, randomized, placebo-controlled trial[END_REF]48,49], five for stroke [START_REF] Gabay | Tocilizumab monotherapy versus adalimumab monotherapy for treatment of rheumatoid arthritis (ADACTA): a randomised, double-blind, controlled phase 4 trial[END_REF][START_REF] Kim | Cardiovascular Safety of Tocilizumab Versus Tumor Necrosis Factor Inhibitors in Patients With Rheumatoid Arthritis: A Multi-Database Cohort Study[END_REF][START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF][START_REF] Westhovens | The safety of infliximab, combined with background treatments, among patients with rheumatoid arthritis and various comorbidities: a large, randomized, placebo-controlled trial[END_REF]38], but not enough data were available for CHF. Unfortunately, PAD was included in the MACE composite criteria in the studies but were not reported separately. Three studies [START_REF] Gottenberg | Similar Rates of Death, Serious Infections, Cancers, Major Cardiovascular Events in Patients Treated with Abatacept, Rituximab and Tocilizumab: Long-Term Registry Data in 4498 Patients with Rheumatoid Arthritis[END_REF][START_REF] Burmester | Tocilizumab combination therapy or monotherapy or methotrexate monotherapy in methotrexate-naive patients with early rheumatoid arthritis: 2-year clinical and radiographic results from the randomised, placebo-controlled FUNCTION trial[END_REF]47] responded to our inclusion criteria but did not reported the number of MACE event, only Hazard Ratio (HR) or only the total number or cardiovascular events (not for each group) which have not been reported in Table 1.

MACE risk with TCZ vs other bDMARD

2017 FUNCTION þ þ þ þ þ þ Emery &al. � [29] 2010 SERENE þ þ þ þ þ þ Emery &al. � [39] 2017 C-EARLY þ þ þ þ þ þ Gabay &al. � [11] 2013 ADACTA þ þ þ þ þ þ Giles &al. � [27] 2016 - þ þ ? ? þ þ Jobanputra &al. [41] 2012 RED SEA þ þ ? þ þ þ Kay &al. � [42] 2008 - þ þ þ þ þ þ Keystone &al. � [32] 2016 GO-FORWARD þ þ þ þ þ þ Kim &al. � [46] 2012 APPEAL þ þ ? þ þ þ Manders &al. � [43] 2015 DREAM-TIME þ þ ? þ þ þ Smolen &al. � [10] 2008 OPTION þ þ þ þ þ þ Smolen &al. [45] 2016 EXXELARATE þ þ þ þ þ þ Smolen &al. � [44] 2015 CERTAIN þ þ þ þ þ þ Westhovens &al. � [34] 2006 - þ þ þ þ þ þ Weisman &al. [35] 2007 - þ þ þ þ þ þ Yamamoto &al. � [48] 2014 J-RAPID þ þ þ þ þ þ
Non randomized trials(ROBINS-I tool)

Author Year Bias due cofounding

Bias in selection of participatnts

Bias in classification of interventio

Bias due to deviations froms interventions

Bias in measurement outcome

Incomplete outcome data

Selective reporting

Al-aly &al. � [START_REF] Al-Aly | Tumor necrosis factor-α blockade, cardiovascular outcomes, and survival in rheumatoid arthritis[END_REF] 2011

? þ þ þ þ þ ? Cardenas &al. [37] 2016 ? þ þ þ þ þ ? Choy &al. � [38] 2017 ? þ þ þ þ þ þ Curtis &al. [17] 2015 ? þ þ þ þ þ þ Geborek &al. � [49] 2002 À þ þ þ þ þ ? Gottenberg &al. [18] 2016 ? þ þ þ þ þ ? (Continued )

MI risk with TCZ vs other bDMARD

The analysis of MI risk included eight studies (four RCT and four cohorts).

Stroke risk with TCZ vs other bDMARD

Five studies were included for stroke event (two RCT and three cohorts).

Comparison of CHF

There was not enough data available to perform a network meta-analysis.

Discussion

We performed the first network meta-analysis comparing the cardiovascular outcomes of TCZ and other biologics. However, we found a lower risk of MACE with RTX in the RCT NMA, which is not significant when we included only cohorts or both designs. This study showed that TCZ has similar cardiovascular outcomes comparing with other bDMARD and csDMARD. TCZ significantly increases lipids levels more than TNFi [START_REF] Gabay | Comparison of lipid and lipid-associated cardiovascular risk marker changes after treatment with tocilizumab or adalimumab in patients with rheumatoid arthritis[END_REF], ABA and RTX [50]. This is one of the reasons why TCZ was initially used with a particular attention in patient with a high cardiovascular risk. Despite this increase, our results show the cardiovascular safety profile of TCZ comparing to the other biologics, especially when we included only RCT in the NMA. We also found less myocardial infarction with TCZ than ABA and TNFi in observational studies. This beneficial effect on myocardial infarction could be explained by the fact that TCZ decreases more lipoprotein A levels, and SAA-HDL than adalimumab in the ADACTA study [START_REF] Gabay | Comparison of lipid and lipid-associated cardiovascular risk marker changes after treatment with tocilizumab or adalimumab in patients with rheumatoid arthritis[END_REF]. Indeed, lipoprotein-A has been associated with MI [51] and the HDL linkage by SSA protein could be responsible for HDL-C loss anti atherogenic function [START_REF] Gabay | Comparison of lipid and lipid-associated cardiovascular risk marker changes after treatment with tocilizumab or adalimumab in patients with rheumatoid arthritis[END_REF]50,52,53]. Furthermore, inflammatory cytokines, particularly IL-1 and IL-6 seem to play a determinant role in the atherosclerotic process. Recently, the CANTOS trial performed in general population shown a significantly lower rate of recurrent cardiovascular events with canakinumab than placebo [START_REF] Ridker | Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease[END_REF]. A cohort study found an improvement of the endothelial function in high risk patients with RA with TCZ but not with TNFi [START_REF] Bacchiega | Interleukin 6 Inhibition and Coronary Artery Disease in a High-Risk Population: A Prospective Community-Based Clinical Study[END_REF]. IL-6 seems strongly involved in the coronary heart disease (CHD), especially via the trans-signaling pathway [START_REF] Morieri | Interleukin-6 "Trans-Signaling" and Ischemic Vascular Disease: The Important Role of Soluble gp130[END_REF][START_REF] Anderson | IL-6 and its receptors in coronary artery disease and acute myocardial infarction[END_REF][START_REF] Vela ´squez | Circulating levels of interleukin 6 soluble receptor and its natural antagonist, sgp130, and the risk of myocardial infarction[END_REF]. Mendelian randomization studies showed that IL-6 up-regulation increases CHD risk [START_REF] Hartaigh | Evaluation of 9 biomarkers for predicting 10-year cardiovascular risk in patients undergoing coronary angiography: findings from the LUdwigshafen RIsk and Cardiovascular Health (LURIC) study[END_REF][START_REF] Niu | Association of interleukin-6 circulating levels with coronary artery disease: a meta-analysis implementing mendelian randomization approach[END_REF]. Conversely, the variant Asp358 causes an increase in the soluble IL-6 receptor (IL-6Rs) and is associated with a reduced risk of coronary artery disease [START_REF]Interleukin-6 receptor pathways in coronary heart disease: a collaborative meta-analysis of 82 studies[END_REF][START_REF] Jansen | Mendelian randomization studies in coronary artery disease[END_REF]. Indeed, in a placebo-RCT in general population with MI, a single dose of TCZ decreases more troponin levels than placebo at day 3 [START_REF] Kobayashi | Association of tocilizumab treatment with changes in measures of regional left ventricular function in rheumatoid arthritis, as assessed by cardiac magnetic resonance imaging[END_REF]. In an observational study Kobayashi & al. found that TCZ treatment in RA patients significantly increased left ventricular ejection fraction and decreased left ventricular mass index comparing to healthy controls [START_REF] Kobayashi | Tocilizumab Treatment Increases Left Ventricular Ejection Fraction and Decreases Left Ventricular Mass Index in Patients with Rheumatoid Arthritis without Cardiac Symptoms: Assessed Using 3.0 Tesla Cardiac Magnetic Resonance Imaging[END_REF]. Finally, in highrisk population of CHD, high IL-6 levels were associated with MI risk, cardiovascular death and all causes death [START_REF] Chen | Interleukin-6, but not C-reactive protein, predicts the occurrence of cardiovascular events after drug-eluting stent for unstable angina[END_REF]. This systematic review and meta-analysis have several strengths. Indeed, we performed an exhaustive review, through four international databases, and two international meetings databases. The included studies showed high quality. RCT were at low risk of bias except for which who were open-label. However, one of these had MACE as primary outcome with an openlabel design. Furthermore this study is not published and was found in the 2016 ACR meetings abstract [START_REF] Giles | Comparative Cardiovascular Safety of Tocilizumab Vs Etanercept in Rheumatoid Arthritis: Results of a Randomized, Parallel-Group, Multicenter, Noninferiority, Phase 4 Clinical Trial[END_REF]. Most of the cohort studies were at "moderate risk of bias" only because of their non-randomized design. We realized a network meta-analysis which allowed us to make indirect comparisons of multiple treatments and thus to analyze a large amount of studies including placebo RCT. Due to multiple comparators, heterogeneity had to be measured which was possible with this technique. Furthermore, we used random effects model even if the heterogeneity test was no statistically significant because it considers fluctuations of sampling and also treatment effect fluctuations due to multiple covariates. Finally, although we restricted our research to English and French languages, no article was excluded because of the language.

? þ þ þ þ þ þ Iannone &al. � [40] 2018 À þ þ þ þ þ ? Jin &al. [31] 2017 þ þ þ þ þ þ ? Kim &al. [15] 2017 þ þ þ þ þ þ þ Kim &al. � [33] 2018 þ þ þ þ þ þ þ Sakai &al. [47] 2015 ? þ þ þ þ þ ? Zhang &al. � [14] 2016 þ þ þ þ þ þ ? RTX,
However, our studies showed some limits. The heterogeneity test was significant for MACE outcome which was controlled by using a random effects model. The transivity hypothesis has not been tested, which is a limitation of the study. Unfortunately, the baseline CV risk was not specified in the included studies, we were unable to carry out an analysis to determine whether this risk was an effect modifier.

Our network meta-analysis illustrates the indication bias in observational studies. Indeed, the beneficial effect of TCZ for MI could be explained by a lesser use of TCZ in high CV risk patients because of the cholesterol increase under treatment. The fact that TCZ is under used in high-risk CV patients is not supported by the literature, the indication bias due to the prudent use of TCZ in high-risk patients is therefore purely hypothetical, not supported by the indirect), TCZ-tocilizumab; csDMARDs-conventional synthetic disease-modifying antirheumatic drugs; TNFitumor necrosis factor inhibitor; ABA-abatacept; RTX-rituximab. https://doi.org/10.1371/journal.pone.0220178.g003 literature, but remains likely. Another explanation is that observational studies were designed to study cardiovascular events, with high sample sizes, unlike RCTs.

Conclusion

Despite these limits, our study showed a good cardiovascular safety profile of TCZ compared to other bDMARD, with potential benefit on MI compared to other bDMARD. Further studies are needed to corroborate these data.

Supporting information

Fig 1 .

 1 Fig 1. Flow chart of the systematic literature review. PubMed/Medline, Web of science, Cochrane library, Science direct and ACR, Annual College of Rheumatology; EULAR, European League Against Rheumatism databases. https://doi.org/10.1371/journal.pone.0220178.g001

Fig 2 .Fig 3 .

 23 Fig 2. NMA with RCT on major adverse cardiac events, myocardial infarction and stroke with TCZ vs other treatments. comparison-Treatment comparison, k-Number of studies providing direct evidence, prop-Direct evidence proportion, nma-Estimated treatment effect (RR) in network meta-analysis, direct-Estimated treatment effect (RR) derived from direct evidence, indirect-Estimated treatment effect (RR) derived from indirect evidence, RoR-Ratio of Ratios (direct versus indirect), p-value-p-value of test for disagreement (direct versus indirect), TCZtocilizumab; csDMARDs-conventional synthetic disease-modifying antirheumatic drugs; TNFi-tumor necrosis factor inhibitor; ABA-abatacept; RTX-rituximab. https://doi.org/10.1371/journal.pone.0220178.g002

Fig 4 .

 4 Fig 4. NMA with both designs (RCT and cohorts) on major adverse cardiac events, myocardial infarction and stroke with TCZ vs other treatments. comparison-Treatment comparison, k-Number of studies providing direct evidence, prop-Direct evidence proportion, nma-Estimated treatment effect (RR) in network meta-analysis, direct -Estimated treatment effect (RR) derived from direct evidence, indirect-Estimated treatment effect (RR) derived from indirect evidence, RoR-Ratio of Ratios (direct versus indirect), p-value-p-value of test for disagreement (direct versus indirect), TCZ-tocilizumab; csDMARDs-conventional synthetic disease-modifying antirheumatic drugs; TNFi-tumor necrosis factor inhibitor; ABA-abatacept; RTX-rituximab. https://doi.org/10.1371/journal.pone.0220178.g004

  The analysis of MACE outcome encompassed 19 studies(11 RCT and 8 cohorts) 12 312 patients were treated by TCZ, 8 123 with RTX, 28 728 with ABA, 45 963 with TNFi and 21 372 with csDMARD. 1 766 MACE were recorded: 125 under TCZ (1.02%), 183 under RTX (2.25%), 656 under ABA (2.28%), 1066 under TNFi (2.32%), 264 under csDMARD (1.24%). First, we included only RCT (n = 11) in the NMA. We found less events with RTX (TCZ vs RTX 5.41 [1.70;17.26]. We found no difference between TCZ and other treatments (1.10 [0.50;2.40] with TNFi, 4.37 [0.43;44.55] with ABA and 1.49[0.77;17.26] with csDMARD) (Fig 2). The results with only observational studies are represented in Fig 3.

When we included both designs (RCT and cohort) we found no difference between TCZ and other treatments: 0.66 [0.42;1.03] with ABA, 1.04 [0.60;1.81] with RTX, 0.78[0.53;1.16] and 0.91 [0.54;1.51] with csDMARD (Fig 4).

Table 2 . Risk of bias assessment (n = 29).

 2

	NS	NS	NS		NS
	TCZ 63.7 87% 27.8% NS 23.59% 14.1% NS NS NS 3 332 2 728 NS 17 17 NS	[14] RTX 2016 64.9 84.4% 30% NS 21.55% 14.84% NS NS NS 7 475 8 424 NS 71 71 NS	TNFi 67.5% 86.7% 27.7% NS 21.19% 15% NS NS NS 35 44 763 NS 359 359 NS	718	ABA 65.6 87% 29.6% NS 22.1% 13.9% NS NS NS 13 18 747 NS 138 138 NS	608	RTX, rituximab; ADA, adalimumab; IFX, infliximab; ETN, etanercept; CTZ, certolizumab pegol; GOL, golimumab; MTX, methotrexate; TNFi, TNF inhibitor; Prevcs, previous csDMARD,	conventional synthetic disease-modifying antirheumatic drugs; PrevB, previous bDMARD biological disease-modifying antirheumatic drugs; PrevCV, previous cardiovascular event; NS, not	specified; PY, patient year	https://doi.org/10.1371/journal.pone.0220178.t001

Table 2 .

 2 (Continued)

	Harrold &al. �	2015
	[30]

  rituximab; ADA, adalimumab; IFX, infliximab; ETN, etanercept; CTZ, certolizumab pegol; GOL, golimumab; MTX, methotrexate; TNFi, TNF inhibitor; csDMARD, conventional synthetic disease-modifying antirheumatic drugs; NS, not specified, PY; patient year; IR incidence rate; RCT randomized controlled trial; ACR, American College of Rheumatology; EULAR, European League Against Rheumatism; + low risk; ? some concerns; -high risk; � , included in NMA

https://doi.org/10.1371/journal.pone.0220178.t002

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ACR Meeting Abstracts

[Internet]

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PLOS ONE | https://doi.org/10.1371/journal.pone.0220178 August 1, 2019

Acknowledgments

BC thanks the French Society of Rheumatology (SFR) because this work has been possible thanks to their financial support.

received financial support from the French society of rheumatology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

All relevant data are within the manuscript and its Supporting Information files.

Author Contributions

Conceptualization: Benjamin Castagne ´, Marie Viprey.

Data curation:

Benjamin Castagne ´, Marie Viprey, Julie Martin. Validation: Marie Viprey, Julie Martin, Anne-Marie Schott, Michel Cucherat, Martin Soubrier.

Writing -original draft: Benjamin Castagne

´.

Writing -review & editing: Julie Martin, Anne-Marie Schott, Michel Cucherat, Martin Soubrier.


Vincent Sarbach-Pulicani
email: vincent.sarbach-pulicani@outlook.com

Profiling Anonymous Authors in the Corsican Autonomist Press of the Interwar Period

Keywords: stylometry, topic modelling, corsican studies, under-ressourced languages, computational history

With the emergence of nationalism in the 19 th century came regionalist movements to assert and claim cultural particularities. Corsica fitted very well within this dynamic and even presented itself as a favourable location for the development of such ideas. The centralization of the state around a strong capital and the policies of assimilation of the indigenous populations on the border with France led certain players to defend these particularisms. It was in this context that the Corsican autonomist newspaper A Muvra was born in May 1920 in Paris, under the impetus of Petru and Matteu Rocca. For almost 19 years, hundreds of authors participated in the writing of this massive dialectal work. This paper presents the results of a research that aimed to carry out author profiling, i.e., to determine the style and subjects covered by an author. The goals of this study were to determine the identity behind certain authors and also to highlight the role pseudonyms played in the newspaper's propaganda. We conducted authorship attribution to achieve the first objective before completing these analyses with topic modelling in order to meet the second one.

Introduction

Corsican studies have focused at length on the Corsican autonomist press of the interwar period, in particular the newspaper A Muvra. Founded in 1920 by Petru Rocca and his brother, they were active for nearly 20 years until the outbreak of the Second World War. During these two decades, several hundred authors contributed to the weekly output of the journal. The historiographical renewal of Corsican autonomism began around the 2000s in order to bring a fresh perspective to the subject. We can cite several important thesis: those by Ysée Rogé [START_REF] Rogé | Le corsisme et l'irrédentisme 1920-1946: histoire du premier mouvement autonomiste corse et de sa compromission par l'Italie fasciste[END_REF], Deborah Paci [START_REF] Paci | Il mito del Risorgimento mediterraneo: Corsica e Malta tra politica e cultura nel ventennio fascista[END_REF], and finally Ange-Toussaint Pietrera [START_REF] Pietrera | Imaginaires nationaux et mythes fondateurs; la construction des multiples socles identitaires de la Corse française à la geste nationaliste[END_REF]. In parallel to these studies, research in late modern history has been particularly flourishing concerning Corsica, especially over the last 20 years. In this regard, the work carried out by Jean-Paul Pellegrinetti is essential. His synthesis on Corsica and the Third Republic is still an authority on the subject [START_REF] Pellegrinetti | La Corse et la République. La vie politique, de la fin du second Empire au début du XXIe siècle[END_REF]. This paper is part of this desire to revitalise historical studies of contemporary Corsica. It also occurs in the context of the increasing development of natural language processing (NLP) for the Corsican language, a central technical issue in our study. For several years, there has been a desire in Corsica to structure and study the evolution of the use of the Corsican language. We can notably mention the work of the linguist Marie-José Dalbera-Stefanaggi with her Nouvel atlas linguistique et ethnographique de la Corse. In the republications of this major work in the 2000s, the author incorporated her work on the creation of a Banque de Données Langue Corse (BDLC). 1 This is the first initiative to lemmatise the Corsican language in its diachrony and diatopy. 2 Since the second part of the 2010s, there has been a significant increase in scholars' thoughts on the tooling of regional languages using NLP [START_REF] Kevers | Outiller une langue peu dotée grâce au TALN: l'exemple du corse et BDLC[END_REF]. Our approach is fully in line with this state of the art. This paper presents is the continuation of a master's thesis written as part of a double degree programme between the École nationale des chartes of Paris and the Università di Pisa [START_REF] Sarbach-Pulicani | Authors profiling in Corsican autonomist press during the interwar pe-riod. Stylometric analysis and topic modeling on "A Muvra[END_REF]. It follows a first thesis that highlighted the major ideological differences between the corsists and the irredentists, despite their obvious proximity. [START_REF] Sarbach-Pulicani | La presse corsiste et irrédentiste des années 1930 : étude comparative et quantitative des revues A Muvra et Corsica antica e moderna entre 1932 et 1939[END_REF] It resulted in the creation a database named Autonomists/Irredentists Database (A/I database). 3 . This work establishes that if the corsists admitted to being part of a common cultural and linguistic entity with Italy, they did not share the same desire for political unification, even if some autonomists came closer to Fascist ideas just before the beginning of the Second World War.

Like any political press, A Muvra has a large number of anonymous authors writing under pseudonyms. While the possibility of individual authors exists, there is also a good chance that these pseudonyms are the result of recurring authors of the journal publishing under their real names. This raises a number of questions about the identity of these anonymous authors as well as the role that a corsist gives to one or more of his pseudonyms. Several preliminary hypotheses can be proposed at this stage, including the deliberate exaggeration of the number of activists, the need for protection against censorship, or the desire to express varying viewpoints. In order to address these inquiries, we will employ two distinct analytical methods. First, we will utilise stylometry to unveil the identities of anonymous authors, and secondly, we will apply topic modelling to gain insights into the themes associated with these pseudonyms. Subsequently, we will engage in an interpretive phase to discern the purpose and characterization an author assigns to their pseudonym. These dual layers of analysis ultimately encapsulate the concept of author profiling, as previously discussed. The analyses and results are all available on a GitHub repository dedicated to this research [START_REF] Sarbach-Pulicani | Stylometry and topic modelling in Corsican language[END_REF].

Datasets construction: starting from scratch

The OCR processing

The main issue surrounding the analysis of such a review is the accessibility of the data. In order to carry out the analyses, the data had to be acquired from the digitised images of the newspapers. Segmentation and OCR presented significant challenges, as well as postprocessing and normalisation (see an example of a front page with Figure 12). We were able to locate two online platforms where our documents are available for download. The images come from two sources: the Bibliothèque nationale de France (BnF) and the Archives départementales de Corse du Sud (ADC). So we used Gallica, the digitization platform of the BnF, and THOT, the platform of the ADC. 4 The fact that these are national institutions means that the digitizations are in the public domain, i.e., open source. After the phase of webscrapping, we got a collection of 375 issues of the Muvra, i.e., approximately 1500 pages from 1921 to 1931.

One of the problems with having images from two different sources is the quality of the images. This raises the question of whether or not it is appropriate to normalise and clean images in order to facilitate OCR processing. The original idea of our research was to clean the documents using binarization with the Otsu method [START_REF] Otsu | A threshold selection method from gray-level histograms[END_REF] followed by a despeckling phase. The "speckling" is a type of noise that corresponds to random clusters of black pixels that impair the intrinsic quality of a binarized image [START_REF] Fracastoro | Deep learning methods for synthetic aperture radar image despeckling: An overview of trends and perspectives[END_REF]. However, the quality of the digitizations, especially from the Archives départementales, varies greatly. While sharpness is not the main problem, it is more a question of stains on the paper or pages damaged by time. This is an inherent problem in the conservation of old newspapers; paper is cheap and not made to last over time. The conservation of these documents is therefore difficult, and this is reflected in the quality of the digitization. Standardising all the images at the same time requires an initial sorting organised according to identical layouts for a gain in OCR quality that is not necessarily guaranteed. So we decided to prefer quantity over quality, even if the normalisation would occur on the raw data.

One of the major challenges in the world of automatic character recognition today is the segmentation of newspapers. Their complex layout requires the training of complex models that are often specific to a type of newspaper. We decided to train a Kraken segmentation model from the XML files in ALTO format available on Gallica, with the help of the eScriptorium platform [START_REF] Kiessling | eScriptorium: an open source platform for historical document analysis[END_REF] and the module ketos. Once the ALTO files were adapted to the good format, we could train the model to segment the images coming from the Archives départementales de Corse du Sud. In order to improve the model, it was necessary to use the tool YALTAi [START_REF] Clérice | You Actually Look Twice At it[END_REF] developed by Thibault Clérice, which allows the use of YOLOv5 [START_REF] Jocher | YOLOv5 by Ultralytics[END_REF], an Ultralytics object detection model, to be adapted for training segmentation models with Kraken. For the text recognition phase, we decided to go for Tesseract-OCR, which includes a Corsican model. We needed to create UZN files readable by this engine in order to follow the coordinates of the image (Figure 1).

Data standardisation

Once we got our raw textual data, we had to classify them according to their language, typology, and author. Then we could perform the cleaning of the textual data, carried out in four main stages:

• The removal of punctuation • Case reduction • Normalization of syntax • Elimination of accents

The most delicate phase in our methodology is the normalisation of the syntax. It is important because, for euphonic reasons, contractions occur in written form in the form of elisions, which reflect the discourse practices of speakers of Corsican. For example, the expression s'è ellu hè ("if he is") becomes s'ell'è in writing. Inversely, restoring the original form of the elision requires taking into account the context of gender and number: ell' can give ellu, ella, elli, or elle. There is also the question of the normalisation rule: should we base ourselves on the syntax of the 20 th century or on the current one? Moreover, a certain number of ambiguities can creep into such a correction, such as the word e, which, depending on the context, can mean either "the" or "and". We should not forget to take into account that Corsican is a "langue par élaboration" or Ausbau language and that, consequently, the syntax has a complexity due to the distinct instantiations according to the authors. In sociolinguistics, this type of language is a variant of a structured language (such as Italian) and set up as a distinct elaborated language [START_REF] Viaut | Marge linguistique territoriale et langues minoritaires[END_REF].

The issue of data normalisation is particularly delicate due to the very nature of our methodology. While topic modelling does not include function words in the analysis because they are meaningless words, stylometry relies mainly on all types of most frequent words. Indeed, to what extent should we normalise the data? Do we lose information if we normalise the syntax of certain terms, or do we gain information? The choices that have been made are recorded in the Python file dedicated to data cleaning. This is nevertheless an important bias for our analysis. Fortunately, the regiolectal diversity of the Corsican language means that the idiomatic features of the authors are characterised by the great variety of the function words used. A thorough normalisation should not alter our analysis too much, even if it constitutes an improvement perspective for our study.

In the end, we obtained a total of 3 corpora of different sizes with a total of almost 1.5 million words (Table 1), with approximately 56.7% of the words in Corsican, 27% in French, and 16.3% in Italian. The main point of improvement in this method of extracting textual data is the balancing of the corpus. While we were able to obtain almost all the articles in the issues on Gallica, the issues on THOT were selected according to our needs, given the variation in the quality of the images. However, this is still quite sufficient for the type of analysis we are carrying out, focusing on a certain number of authors. Details of the samples selected for this study can be found in the appendix (Table 4).

Method proposed: two layers of analysis

The last advances in stylometry have been made with the use of machine learning algorithms.

Recent examples include the work of Jean-Baptiste Camps and Florian Cafiero, who used SVM classifier algorithms to identify the authors of the American conspiracy forum QAnon [START_REF] Cafiero | Who could be behind QAnon? Authorship attribution with supervised machine-learning[END_REF]. This means that we can now tackle the question of the statistical units to be analysed with our algorithms, whether using machine learning techniques or distance metrics. The two French researchers chose to work on character 3-grams because of the "increase robustness", they are "known to reduce sparsity and perform well in attribution studies". In reality, the features to be analysed vary according to the nature of the corpus and the quality of the data. One example is the measurement of verses in poetic works to measure an author's style [START_REF] Beaudouin | Contribution de la métrique à la stylométrie[END_REF] and even the rhymes in mediaeval texts like Mike Kestemont did in 2012 [START_REF] Kestemont | Robust rhymes? The stability of authorial style in medieval narratives[END_REF]. For the previous thesis, we managed to compare the results obtained with the SVM with a metric distance, the Delta score as defined by John Burrow in 2002 [START_REF] Burrows | Delta': a measure of stylistic difference and a guide to likely authorship[END_REF], in order to confirm them considering the limited length of the corpora. The objective of this double layer of analysis was to confirm the results and determine the best possible approach for our corpus. This paper will focus on the machine learning approach, but the results obtained with Burrow's Delta that confirmed the SVM methods are available on the GitHub repository [START_REF] Sarbach-Pulicani | Stylometry and topic modelling in Corsican language[END_REF]. The script being used is the SuperStyl one developed by Jean-Baptiste Camps in 2021 [START_REF] Camps | SUPERvised STYLometry (SuperStyl)[END_REF]. Whatever the authors and pseudonyms tested, we excluded poetic texts part in prose or verse from the stylometric due to their specificities. It is very important to vary the hyperparameters available to us in order to optimise machine learning. To do this, the SuperStyl algorithms allow us great flexibility in the options to be taken into account. After various tests presented in the benchmark (Table 6), we chose those parameters: the statistical units are the most frequent words; we apply the PCA (Principal Component Analysis) for dimensional reduction; the cross-validation is carried out with the "Leave-One Out" method; and we balance the dataset with the "upsampling". This technique consists of isolating a portion of our minority corpus and sampling an equal number of examples from the majority class, as explained by Joseph Barr in 2022 [START_REF] Barr | Upsampling, a comparative study with new ideas[END_REF]. Once the model has been trained, we apply it to the unseen data. In view of the large number of candidates for the second experiment, we initially subdivided them into two groups in order to obtain more precise results before carrying out an analysis on the whole corpus.

Concerning topic modelling, the LDA (Latent Dirichlet Allocation) is a method based on a term-document matrix. This method is based on the assumption that "documents are represented as random mixtures of latent topics, where each topic is characterised by a distribution of words". The LSI (Latent Semantic Indexing), on the other hand, consists of creating a semantic space based on a corpus in which similarities between words or documents are calculated on a statistical scale. Each of these methods has its own advantages and disadvantages that need to be taken into account, hence the importance of the notion of comparability inherent in our study [START_REF] Cvitanic | LDA v. LSA: A comparison of two computational text analysis tools for the functional categorization of patents[END_REF]. In 2020, a group of researchers set out to compare the two methods by training them on a corpus of BBC articles [START_REF] Kalepalli | Effective comparison of LDA with LSA for topic modelling[END_REF]. The results of their research revealed that LSI is more effective when dealing with a large amount of data and fewer iterations than LDA, while the latter is more suitable for smaller corpora. The idea is to present here the most interesting results with an empirical observation of the results obtained as a form of intrinsic evaluation. In the long term, implementing more effective evaluation metrics such as coherence would be very relevant, even if it is not necessary in our case, given that we are modelling general themes rather than assigning a label to each article. To do so, we used the Gensim package for Python, which offers wide possibilities for performing both LSI and LDA techniques. The different experiments presented in the appendix, along with the hyperparameters and methods used, are detailed in the summary table (Table 5). Table 8 serves as a glossary containing pertinent words that were modelled in the course of the experiments.

The vocabulary plays an essential role in topic modelling. The words chosen to be taken into account in topic modelling must not be too numerous, as training the model can be extremely time-consuming. The number of documents and the vocabulary chosen will therefore play a central role among the various biases to be applied. Unlike stylometry, function words are of no interest because they are considered to be empty words, i.e., words without a significant meaning but serve to add details to the sentence [START_REF] Arun | Stopword graphs and authorship attribution in text corpora[END_REF]. We had to create a specific list of stopwords for our Corsican corpus (Table 7) due to the absence of a basic language toolkit [START_REF] Kevers | Towards a Corsican Basic Language Resource Kit[END_REF]. The list creation process occurred in two phases: initially, it involved comparing it with an Italian list that contained overlapping stopwords with Corsican. Following that, it consisted of the examination of various corpora, including the Muvra dataset. This examination led to the identification of the most frequent words, followed by a selection between stopwords. The idea is therefore to remove them in order to reduce the vocabulary. But there is also the case of hapax or infrequent words, as well as frequent words that are not stopwords, such as "corsica" in this case. One solution is to include the notion of statistical entropy in the choice of vocabulary as presented by Susan Dumais in a 1992 article [START_REF] Dumais | Enhancing performance in latent semantic indexing (LSI) retrieval[END_REF] with the following formula:

𝐸 = 1 -∑ 𝑗 𝑝 𝑖,𝑗 𝑙𝑜𝑔(𝑝 𝑖,𝑗 ) 𝑙𝑜𝑔(𝑛𝑑𝑜𝑐𝑠) 𝑎𝑛𝑑 𝑝 𝑖,𝑗 = 𝑡𝑓 𝑖,𝑗 𝑔𝑓 𝑖
In this equation, ndocs represents the number of documents, tf is the frequency of the term i in the document j, and gf is the overall frequency of the term i. The idea is to calculate the entropy of each word in the corpus and to select vocabulary within a defined interval.

Results

The two pseudonyms chosen

The aim is to test our methodology on two different pseudonyms. The first, P. di B., allows us to check the reliability of our tools on a relatively small corpus in Corsican by confirming the identity of the author. The second, Altore, gives us the opportunity to test these tools on a completely unknown author, leaving us free to interpret and choose the candidates.

The pseudonym P. di B. is a name that appears fairly regularly in the writings of the Muvra. A number of articles were published under this pseudonym, and it is generally accepted that it is actually Petru Rocca, as mentioned by Carmine Starace in the pages of his Bibliografia della Corsica [START_REF] Starace | Bibliografia della Corsica, Centro di studi per la Corsica, Istituto per gli studi di politica internazionale[END_REF]. This pseudonym is believed to be the initials of his mother's surname, Maria Saveria Rocca-Pozzo di Borgo. The latter had remained very close to her sons Petru and Matteu, even publishing drawings in the Muvra. Confirming the writings of contemporary actors from this period also makes it possible to verify the rigour of their anthological work. It is also an excellent way of testing our methodology in a more or less reliable setting.

The other pseudonym seen in this paper is Altore. It is directly inspired by the lake of the same name in the Asco valley, in the old Caccia pieve within the region of the same name. Altore is the author of Lettere aiaccine, the letters from Ajaccio, which often appeared on the front page of the newspaper. In this format, he covers all the subjects of society and politics in general in an open, family-friendly letter format. Our corpus contains 62 of these letters, all written in the Corsican language. The difficulty with this part of our study is that we have no information or clues about the real author behind this pseudonym. Nevertheless, its presence on the front pages of many issues at least testifies to the importance attached to this particular section and therefore to its author.

Concerning the candidates, apart from Petru Rocca, who seems obvious to include in the analysis given the information we provided earlier, we decided to choose two other potential authors. The first is Martinu Appinzapalu, a pseudonym of the Corsican priest Dumenicu Carlotti and symbol of the religious aspect of the insular's autonomist struggle at the time, who published numerous articles throughout the paper's existence and was part of the Partitu Corsu d'Azione, the political party attached to the Muvra. The second is Marcellu Alessandri di Chidazzu, one of the authors most involved in the writing and a fervent defender of the irredentist cause.

First experiment: P. di B.

The evaluation of the trained model is presented in the table 2, we got an accuracy of 0.95. We then obtain a file with the predictions of the author of the articles and the results of the decision function that "tells us how close each sample is to the hyperplane separating each class" [START_REF] Cafiero | Psyché'as a Rosetta Stone? Assessing Collaborative Authorship in the French 17th Century Theatre[END_REF]. A negative value means that the sample is outside; a positive value means it is inside. The higher the score, the greater the probability that this sample has been written by the candidate. By applying this function to our study, we get the figure 2. We have also added the identifiers of articles written by P. di B. whose authorship has not been attributed to Petru Rocca. On the whole, however, almost all the articles were attributed to Petru Rocca. Of the 34 articles in the test corpus, 26 are attributed to the director of the Muvra, i.e., 76% of them. But what is even more interesting to study is the behaviour of the curves on the decision function graph. On average, the decision function scores are much higher for Petru Rocca's texts. Petru Rocca is an expert in this field, as nearly five different identities are attributed to him in the various anthologies and studies carried out on him. We find his signature, Petru Rocca or Pierre Rocca, and the pseudonyms Pasquale Manfredi, P. di B, and P. di C. In view of the stylometric results, we can assume that these various identities attributed to him are indeed his own. In order to optimise the performance of our stylometry models, several parameters need to be taken into account, such as the number of k topics, iterations, words, and passes. Petru Rocca writes mainly in Corsican, although he does leave an important place for French. He also writes a little in Italian, but there are too few texts to be relevant. If we can reference 139 articles written by Rocca in total, we performed the LDA on sub-corpora according to language and pseudonym ( Figures 4,[START_REF] Kevers | Outiller une langue peu dotée grâce au TALN: l'exemple du corse et BDLC[END_REF][START_REF] Sarbach-Pulicani | Authors profiling in Corsican autonomist press during the interwar pe-riod. Stylometric analysis and topic modeling on "A Muvra[END_REF][START_REF] Sarbach-Pulicani | La presse corsiste et irrédentiste des années 1930 : étude comparative et quantitative des revues A Muvra et Corsica antica e moderna entre 1932 et 1939[END_REF][START_REF] Sarbach-Pulicani | Stylometry and topic modelling in Corsican language[END_REF]. It is important to note that for reasons of data quantity, we have grouped together in the same sub-corpus the texts signed by Petru Rocca and Pierre Rocca as well as the texts signed by P. di B. and P. di C. We assume that these have the same utility, but this is obviously a point to be improved in further analyses of the question.

The pseudonyms seem to allow Petru Rocca to evoke a wider spectrum of specific subjects that remain around political and cultural current affairs. Similarly, the use of language doesn't seem to be part of any attempt to separate themes, with French and Corsican acting more as a complement to each other, even if the local dialect seems to be used more to address cultural notions. How then to explain the use of several pseudonyms to express himself in his own newspaper? Let's not forget that he is in fact the director of the Muvra. This can be attributed to propaganda objectives. Indeed, even though there are a large number of contributors, there are very few who are really involved in the corsist struggle over the long term. For Rocca, it would be a question of inflating the numbers of contributors a little in order to get a more substantial core of regular authors to appear. It's not all ideology, and there are sometimes simpler justifications to understand the muvrists' approach. This reason can also be seen in the public demonstrations organised by the autonomists. Thus, in 1934, a number of participants are mentioned in the sixth edition of the merendelle d'i pueti còrsi. 5 The list includes Dumenicu Carlotti, Eugeniu Grimaldi, Petru Rocca, and a certain Pasquale Manfredi. In the same way as we confirmed Petru Rocca's authorship of the texts of P. di B., we carried out the stylometric analysis of those of Altore using the SVM classifier. For the candidates, we chose a wide range of possible authors among the most important ones in the Muvra. For this experiment, the first sub-group mentioned above was made up of Ghjanettu Notini, Victor Gianviti, Dumenicu Antone Versini and Marcellu Alessandri. The second was made up of Simon'Ghjuvanni Vinciguerra, Orsu Francescu Piazzoli, Petru Rocca and Dumenicu Carlotti.

Second experiment: Altore

We thus obtain an accuracy of about 0.86 and a model quite good, as seen on the table 3. This test bears witness to another important aspect of stylometry that has not yet really been addressed in this paper: the notion of corpus size as a function of the number of candidates. This echoes the article by Eder Maciej published in 2015 at Oxford University [START_REF] Eder | Does size matter? Authorship attribution, small samples, big problem[END_REF] where he stated that "the effectiveness of attribution depends on corpus size and particularly on the number of authors tested".

The results of the decision function (Figure 3) show us that Ghjanettu Notini is the most likely candidate among the panel of candidates. But stylometry, like any computational method used in the field of digital humanities, also requires more in-depth research with "close reading". Numbers are not proof. Ghjanettu Notini was born on December 4, 1890, in San Petru di Venacu, in the old pieve of Venacu in Corsica's Curtinese region. Interestingly enough, this region of central Corsica is relatively close to Lake Altore. He was a Corsican poet and writer who contributed for many years to the Muvra under the pseudonym U Sampetracciu. Nicknamed the "Corsican Molière", according to Ghjacumu Thiers, he was the founder of the Teatru corsu di A Muvra in the early years of the newspaper and a loyal contributor.

We can notice certain terms that come up frequently on the wordcloud that visualises the results of topic modelling on Altore (Figure 9), such as "corsu" or "corsica". This brings us faceto-face with our vocabulary selection methodology. These words are very frequent but remain essential in the context of a Corsican autonomist newspaper. Nevertheless, certain trends stand out, with political issues omnipresent in these lettere aiaccine. In particular, there is the notion of the French politician and industrialist Paul Lederlin, who was elected Senator for Corsica in 1930. For U Sampetracciu (Figures 10,[START_REF] Kiessling | eScriptorium: an open source platform for historical document analysis[END_REF], we see that the plays written by Ghjanettu Notini are particularly dominant in the detection of topics. This can be seen thanks to the large number of first names, typical of the theatrical style, which incorporates a lot of dialogue. Other elements highlight this, such as the presence of the onomatopoeia "Ah" or the term "scena" (scene). We can also observe the poetic dimension of Notini's work with Topic 3 of the LDA: we find there the lexical field typical of Corsican poems with the importance of the "mamma" (mother).

It seems fairly obvious that the Corsican author seems more inclined to evoke political and topical themes with the pseudonym. He does this in a very particular literary style, that of the open letter, which corresponds quite well to Notini's great talent for writing. However, Notini did not hesitate to raise these intrinsically political issues in his plays. Likewise, his poetry does not appear to be a simple ode to the beauty of Corsica but a complete reworking of the island's poetic traditions through the prism of the lamentu, a poetic style cherished by the muvrists.

Further research

While this research shows promise, it is important to acknowledge its limitations, which are closely intertwined with its strengths. In the long run, it would be pertinent to develop a dedicated OCR model for recognising printed Corsican text. Additionally, exploring the possibility This article has highlighted the constraints of using topic modelling techniques, which may not be the most suitable approach for detecting word characteristics. Considering this, alternative methods like frequency-based analysis could be more appropriate, given our knowledge of the specific vocabulary found in the Muvra dataset. Moreover, the time invested in removing stopwords might have been unnecessary, as demonstrated by the experiments conducted by Alexandra Schoffield and her colleagues [START_REF] Schofield | Pulling Out the Stops: Rethinking Stopword Removal for Topic Models[END_REF]. Lastly, in terms of stylometric analysis, it is essential to conduct it on the entire newspaper corpus to validate the obtained results, and this should coincide with a more careful selection of candidates for analysis.

Conclusion

The dual nature of pseudonym usage can also be clarified by considering how we employ it. An identity can be used to evoke more sensitive subjects that we wouldn't discuss without it. Ghjanettu Notini makes no secret of the fact that he is U Sampetracciu when he writes his plays and poetry. Even if he tackles specific political themes, he never goes too far and effectively protects himself from criticism behind his dramatic work. But it's thanks to his hypothetical identity as Altore that Notini can really express his intentions, with more assertive political discourse and fewer filters. On the contrary, the use of a pseudonym may not have a purely ideological role but a more propagandist one, as in the case of P. di B for Petru Rocca.

Studying a weekly newspaper spanning almost 20 years represents a real technical challenge that forces us to make choices. Confronted with the intricate nature presented by the numerous metadata within our dataset, we had to make choices and apply biases in order to obtain an overview of what computational methods can offer in the study of such a corpus. It would be possible to perform a stylometric analysis on all anonymous authors or topic modelling on every combination of articles, but it would be time-consuming and represent a possible improvement to this research. In addition to determining the authorship of certain pseudonyms and the role of others, the question was also to work on an under-resourced language. The aim is to encourage this type of study in areas other than pure linguistics, as can be done at the Università di Corsica. While the complexity of the subject is a fact, it does not prevent us from obtaining coherent and promising results for the future. With better preparation of the data, as part of a broader project that would include more resources to allocate to the research, this subject has a lot of potential.

Figure 1 :

 1 Figure 1: Newspaper Page OCR Phase Pipeline

Figure 2 :

 2 Figure 2: Value of the Decision Function for P. di B.

Figure 3 :

 3 Figure 3: Value of the Decision Function for Altore

Figure 5 :

 5 Figure 5: LDA Analysis on Petru Rocca

Figure 6 :

 6 Figure 6: LDA Analysis on Pasquale Manfredi

Figure 7 :

 7 Figure 7: LDA Analysis on Pasquale Manfredi

Figure 8 :

 8 Figure 8: LDA Analysis on P. di B.

Figure 9 :

 9 Figure 9: LDA Anaylisis on Altore

Figure 10 :

 10 Figure 10: LSI Analysis on U Sampetracciu

Figure 11 :

 11 Figure 11: LDA Analysis on U Sampetracciu

Figure 12 :

 12 Figure 12: Example of a Muvra Front Page

Table 1

 1 Length of the Different Corpora.

	Corpus	Word count
	Corsican	897965
	French	380457
	Italian	263095
	Total	1541517

Table 2

 2 Detailed Class Scores using SVM for P. di B. -Leave-One-Out -PCA -Word-Tokens -Upsampling.

	Candidate	Precision Recall F1-score Support
	ALESSANDRI	0.96	0.90	0.93	50
	CARLOTTI	0.95	0.97	0.96	89
	ROCCA	0.92	0.96	0.94	50
	macro avg	0.94	0.94	0.94	164
	weighted avg	0.95	0.95	0.94	164

Table 3

 3 Detailed Class Scores for Altore -Leave-One Out -PCA -Word-Tokens -Upsampling

	Candidate	Precision Recall F1-score Support
	VINCIGUERRA	0.92	0.91	0.22	89
	PIAZZOLI	0.83	0.68	0.75	50
	ALESSANDRI	0.95	0.82	0.88	50
	VERSINI	0.96	0.89	0.92	53
	CARLOTTI	0.86	0.96	0.90	89
	ROCCA	0.69	0.88	0.77	25
	NOTINI	0.81	0.74	0.77	81
	GIANVITI	0.76	0.95	0.85	43
	macro avg	0.85	0.85	0.85	480
	weighted avg	0.86	0.86	0.86	480

Table 7

 7 List of Regiolectal and Diachronic Corsican Stopwords

	li	com	le	e	u	a
	la	ancu	unn	ellu	elli	iddu
	cu	ju	ja	cume	ella	elle
	quellu	quelle	quelli	quella	so	aghju
	aghiu	he	simu	avemu	site	hannu
	hanu	pe	par	seraghiu	sera	sara
	oramai	tuttu	chi	quessu	quessa	quesse
	quessi	bellu	bonu	bona	bon	boni
	bone	boni	be	benche	mo	lu
	idda	incu	nostru	vostru	cusi	cun
	st	bi	micca	altru	to	avia
	stu	quandu	dopu	ca	ava	sottu
	pocu	tutt	ind	inde	unu	tantu
	ssu	idde	dui	ghje	fattu	vo
	eiu	gran	bella	eccu	cum	nun
	quantu	nantu	caru	cara	cari	mi
	esse	sti	sta	ste	ti	vi
	ssa	ssu	ssi	sse	che	perche
	dunque	coi	noi	di	da	si
	ci	un	una	ma	nostri	nostra
	nostre	si	qui	ogni	cio	piu
	per	ha	qualchi	ne	in	fa
	tu	tutte	tutta	tutti	era	no
	dinu	dino	sopra	sotto	mio	mo
	so	quand	duve	me	seraghju	po
	voi	non	parchi	ad	de	pa

Table 8

 8 Glossary of Relevant Words Present in the Topics

	Word	Language	Translation	Word	Language	Translation
	affaire	french	business	manu	corsican	hand
	affare	corsican	business	marseglia	corsican	Marseille
	ami	french	friend	matrimoniu	corsican	mariage
	amore	corsican	love	megliu	corsican	better
	article	french	article	merre	corsican	mayor
	babbu	corsican	father, dad	ministru	corsican	minister
	barbare	french	barbarian	minuranze	corsican	minority
	bien	french	good	moda	corsican	mode
	canta	corsican	to sing	mondu	corsican	world
	centrale	corsican	central	monsieur	french	sir
	chemin	french	path	nasitortu	corsican	hook nose
	concours	french	competition	naziunale	corsican	national
	confrere	french	fellow	oghie	corsican	today
	contre	french	against	omu	corsican	man
	core	corsican	heart	paese	corsican	country, village
	corse	french	Corsica/n	parigi	corsican	Paris
	corsu/a/e/i	corsican	Corsican	parti	french	party (political)
	croce	corsican	cross	passager	french	passenger
	cumitatu	corsican	board	patrie	french	homeland
	cummissione	corsican	commission	pays	french	country
	cumpagnu	corsican	comrade	poetes	french	poets
	cumpare	corsican	mate	politique	french	politic
	directeur	french	director	populu	corsican	people
	droit	french	right	postal/aux	french	postal, mailing
	elettori	corsican	electors	presse	french	press
	esprit	french	spirit	prete	corsican	priest
	fede	corsican	faith	prima	corsican	first
	federazione	corsican	federation	primavera	corsican	spring
	fonctionnaire	french	civil servant	prisidente	corsican	president
	français	french	French	prix	french	price
	francese	corsican	French	projet	french	project
	franchi	corsican	franc (currency)	prova	corsican	try
	francia	corsican	France	pueti	corsican	poets
	fuir	french	to run away	pulitica	corsican	politic
	gauche	french	left	raghione	corsican	reason
	giurnale	corsican	journal	razza	corsican	race
	gouvernement	french	government	sangue	corsican	blood
	guerra	corsican	war	santu/a	corsican	saint
	guvernu	corsican	government	scena	corsican	scene
	histoire	french	history	separatisti	corsican	separatists
	honneur	french	honor	sgio, scio	corsican	sir
	ile	french	island	sicondu	corsican	second
	isula	corsican	island	stampa	corsican	press
	italie	french	Italy	statu	corsican	state
	italien/ne	french	Italian	surete	french	security
	jente	corsican	people	teatru	corsican	theatre
	jeune	french	young	temps	french	time
	jornu	corsican	day	varghiolu	corsican	smallpox
	jour	french	day	vergogna	corsican	shame
	legge	corsican	law	vita	corsican	life
	liberta	corsican	liberty	vitesse	french	speed
	lingua	corsican	langage	vole	corsican	to want

https://bdlc.univ-corse.fr/bdlc/corse.php

This database, which includes a wide range of possibilities, was created on the basis of a vast and particularly impressive field survey.

https://heurist.huma-num.fr/heurist/?db=vsp_presse_corsiste_irredentiste

https://gallica.bnf.fr/accueil/en/content/accueil-en?mode=desktop | http://archives.isula.corsica/Internet_THOT/ FrmSommaireFrame.asp

A Muvra, n°527-1934/09/01-10.

Acknowledgments

I would like to thank Jean-Baptiste Camps and Alessandro Lenci for their supervision of this research. Although this paper is the conclusion of a two-year dissertation, it is also the fruit of cooperation with several researchers, including Angelo Mario Del Grosso and Federico Boschetti, members of the CNR Pisa.

Appendix