Transcultural Adaptation and Validation of a Spanish Version of the Myasthenia Gravis Composite Scale (P3.131)

Objective: To validate and make a transcultural adaptation of a Spanish version of the MGC, for application in our population. Background: MG is an autoimmune disease that affects different structures of the muscular endplate. The main signs and symptoms reveal the fatigability and weakness of the affected muscles. Myasthenia Gravis Composite Scale (MGC) is a scale to evaluate severity and follow up patients with MG, which is validated in an English version. It used is recommended for clinical practice and trials. Methods: 35 MG patients were included since 01-02-2015 to 01-6-2015. Through an adaptation process, a pilot Spanish questionary was made, pre tested and revised by experts in MG, an evaluation of the confiability (test, re-test) and a validation of the concurrent criteria. Sample calculation: Confiability test- re test: 35 patients. Expected sensibility of 99[percnt], alfa error of 0.05 and estimated correlation of 0.7. Questionary adaptation: author authorization, 3 independent and blinded translations, creation of an unique version, test-re test, internal consistency.Validity: correlation between MGC and MG-ADL (Gold Standard Results: The population included in the validation study do not have significant differences with the population included in the original design. All items showed kappa agreement higher than 0.8 (pu003c0.0001). The fiability of each item had a with the total score obtained a high Cronbach alfa. The total score agreement was 97,1[percnt] by using Bland Altman method Conclusions: The results of adaptation, confiability and validation criteria of the Spanish version of MGC were satisfactory.The MGC scale is an useful tool to evaluate patients with MG. Disclosure: Dr. rugiero has nothing to disclose. Dr. Bettini has nothing to disclose. Dr. genco has nothing to disclose. Dr. araoz has nothing to disclose. Dr. posadas martinez has nothing to disclose. Dr. dawidowski has nothing to disclose. Dr. perez has nothing to disclose. Dr. Cristiano has received personal compensation for activities with Bayer, Biogen Idec, Merck, and Novartis.