Essential tremor (ET) is one of the most common movement disorders, with a prevalence of 4.6% among people over 65 years of age. The diagnosis remains clinical. A clinical follow-up of 3 years is required to reduce the chances of further development of other neurological signs (eg, dystonia, parkinsonism, or ataxia). Misdiagnosis is common, with frequent misclassification with respect to other movement disorders, especially Parkinson's disease. Various studies have suggested that up to 37-50% of ET cases have other neurological disorders. These results have a number of potential clinical implications. One is that misdiagnosis is the beginning of errors in treatment. In addition, many of these diseases have a family component. There are as yet no specific biomarkers or imaging procedures to diagnose ET.

Parkinson's disease is the second most frequent neurodegenerative disease, with an incidence between 13.4 and 20.5 per 100,000 inhabitants and a prevalence between 100 and 1,000 cases per 100,000 inhabitants. A peculiar element is the deterioration of the calligraphy. The letter is usually small, poorly formed, imprecise, insecure and these alterations can be very early, sometimes preceding the onset of the rest of the symptoms by years. Dysgraphia (difficulty writing due to impaired coordination) is a well-known motor symptom, but one that has been poorly evaluated since its assessment is difficult.

Our proposal consists of creating a software that analyzes the characteristics of the writing (a
typical sentence and the copy of a spiral) and based on some parameters, after analyzing the results, gives a diagnostic orientation on the type of tremor that the subject presents.

It is foreseeable that we will find objective differences in the graph of patients with different types of tremor. If the results are positive, this technology opens a new perspective for the objective diagnosis and follow-up of these patients. The development of these methods favors the diagnostic process at a lower cost, more sustainable, of high quality, non-invasive and easily adaptable to users. From a social and economic point of view, they can be very valuable and beneficial in really complex environments.