Even at the disease onset, about 70% of patients with multiple sclerosis (MS) suffer from cognitive impairment that impacts quality of life. Currently, some speed processing tests are used, such as SDMT ( symbol digit modalities test ), CSCT (information treatment speed evaluation) and WAIS-IV (Weschler Adult Intelligence Scale ). Their inconvenient are the improvement of scores in test-retest, and some difficulties doing the tests due to motor or visual impairment that might be reported. The XO test is fast, cheap and easy to use during medical consult by neurologists. It seems to be correlated to results of speed processing tests, and probably to some executive functions tests too. Asthenia, anxiety, depression and pain are likely to have a negative influence on tests results. Screening every patients with a short test aims to detect patients with cognitive impairment earlier. After a positive screening test, and to better characterize cognitive impairment, they will undergo a neuropsychological test battery. Depending on the alteration, adapted workstation, financial support, technical and human helps will be implemented in order to improve the daily-living of patients.

This study aims to approve the XO as a screening test of cognitive impairment in MS patients. We will study the relationship between XO test, and SDMT, CSCT, WAIS-IV, and also with questionnaires about pain, asthenia (FSS, Fatigue Severity Scale), anxiety and depression (HAD, Hospital Anxiety and Depression ). The XO test will be standardized using a healthy population.

Even at the disease onset, about 70% of patients with multiple sclerosis (MS) suffer from cognitive impairment that impacts quality of life. Currently, some speed processing tests are used, such as SDMT, CSCT and WAIS-IV. Their inconvenient are the improvement of scores in test-retest, and some difficulties doing the tests due to motor or visual impairment that might be reported. The XO test is fast, cheap and easy to use during medical consult by neurologists. It seems to be correlated to results of speed processing tests, and probably to some executive functions tests too. Asthenia, anxiety, depression and pain are likely to have a negative influence on tests results. Screening every patients with a short test aims to detect patients with cognitive impairment earlier. After a positive screening test, and to better characterize cognitive impairment, they will undergo a neuropsychological test battery. Depending on the alteration, adapted workstation, financial support, technical and human helps will be implemented in order to improve the daily-living of patients.

This study aims to approve the XO as a screening test of cognitive impairment in MS patients. We will study the relationship between XO test, and SDMT, CSCT, WAIS-IV, and also with questionnaires about pain, asthenia (FSS), anxiety and depression (HAD). The XO test will be standardized using a healthy population. 140 multiple sclerosis patients (90 relapsing remitting, and 50 progressive) and 400 healthy controls must be recruited.

Multiple sclerosis patients included must :

• Be men or women aged 18 or more
• Be diagnosed with Multiple Sclerosis (MacDonald criteria, 2017)
• Absence of relapse in the previous month
• Be mother-tongue French, or speaking French fluently
• Be covered by French social security

Healthy controls included must :

• Be men or women aged 18 or more
• Suffer from no pathology that might be incompatible with the study

People who can't be included :

• Patients or controls declining participation to the study, or legally protected, pregnant or breastfeeding women
• Patients suffering from another neurological disease, psychiatric disorder, or developmental abnormalities that were diagnosed before multiple sclerosis
• Patients with cranial trauma, relapse that ended less than 1 month before, or depression in the last 3 months
• Patients with severe motor or visual disabilities There are 4 centers. This is a prospective cohort study, in which data will be collected during a single appointment.

The score obtained doing XO test is the dependent variable that will be compared to the variables due to speed processing and executive functions tests. Test-retest of XO test will also be assessed. The percentage of wrong answers doing XO test will be investigated.

The study is going to last 18 months. Every patient (140) and healthy control (400) will fill in all the tests and questionnaires, except FSS (fatigue severity scale), in a random order during a single appointment. The FSS will be filled in by patients only. All 400 healthy controls will be divided in 20 groups of 20 people, due to gender, age (5 classes: 18-33, 34-43, 44-54, 55-64, and more than 65 years old), and level of education (graduated or not). 60 of them will undergo the XO test at the beginning and again at the end of the appointment to investigate the test-retest effect.

Inclusion criteria :

• Multiple sclerosis patients included must :
• Be men or women aged 18 or more
• Be diagnosed Multiple Sclerosis (MacDonald criteria, 2017)
• No relapse in the previous month
• Be mother-tongue French, or speaking French fluently
• Be covered by French social security

Healthy controls included must :

• Be men or women aged 18 or more
• Suffer from no pathology that might be incompatible with the study

Exclusion criteria :

• - Patients or controls declining participation to the study, or legally protected, pregnant or breastfeeding women
• Patients suffering from another neurological disease, psychiatric disorder, or developmental abnormalities that were diagnosed before multiple sclerosis
• Patients with cranial trauma, relapse that ended less than 1 month before, or depression less than 3 months
• Patients with severe motor or visual disabilities