Quantitative Myasthenia Gravis Score: a Brazilian multicenter study for translation, cultural adaptation and validation

ABSTRACT

Objective

To perform the translation, cross-cultural adaptation and validation of the Quantitative Myasthenia Gravis Score (QMGS) to Brazilian Portuguese in accordance with international ethical standards.

Methods

The following steps were taken: (1) implementation of the translation protocol and transcultural adaptation, (2) validation of the adapted content, and (3) assessment of reliability. To check intra- and inter-observer reproducibility, each patient underwent two interviews with interviewer-A and one with B. The QMGS was compared to the Myasthenia Gravis Composite Scale and Myasthenia-specific Quality of Life Questionnaire.

Results

Our study group consisted of 30 patients, with a mean age of 47.6±11.4 years and a mean duration of illness of 11.33±8.49 years. Correlation between the QMGS and MGC was very strong (r = 0.928; p < 0.001) and substantial between the QMGS and MG-QOL 15 (r = 0.737; p < 0.001).

Conclusion

The Brazilian Portuguese translation, and validation of the QMGS was successfully performed.

RESUMO

Objetivo

O objetivo foi realizar a tradução e validação do teste quantitativo para Miastenia Gravis (QMGS) para Português do Brasil, de acordo com as diretrizes internacionais.

Métodos

Foram realizadas as etapas de implementação do protocolo de tradução e adaptação transcultural, validação do conteúdo adaptado e avaliação da confiabilidade. Para verificar a reprodutibilidade intra e inter-observador cada paciente foi submetido a duas entrevistas por um entrevistador-A e um B. O QMGS foi comparado ao MG Composite Scale e Myasthenia-specific Quality of Life Questionnaire.

Resultados

O estudo inclui 30 pacientes, com a média de idade de 47,6±11,4 anos e tempo médio de doença de 11,33±8,49 anos. A correlação entre QMGS e MGC apresentou-se muito forte (r = 0,928; p < 0,001) e substancial entre QMGS e MG-QOL 15 (r = 0,737; p < 0,001).

Conclusão

A tradução, e validação do QMGS para o português do Brasil foi realizada com sucesso.

myasthenia gravis - cross-cultural comparison - translations - validation studies

miastenia gravis - comparação transcultural - traduções - estudos de validação

• References

• 1 Meriggioli MN, Sanders DB. Autoimmune myasthenia gravis: emerging clinical and biological heterogeneity. Lancet Neurol. 2009;8(5):475-90. https://doi.org/10.1016/S1474-4422(09)70063-8
• 2 Hoch W, McConville J, Helms S, Newsom-Davis J, Melms A, Vicent A. Auto-antibodies to the receptor tyrosine kinase MuSK in patients with myasthenia gravis without acetylcholine receptor antibodies. Nat Med. 2001;7(3):365-8. https://doi.org/10.1038/85520
• 3 Higuchi O, Hamuro J, Motomura M, Yamanashi Y. Autoantibodies to low-density lipoprotein receptor-related protein 4 in myasthenia gravis. Ann Neurol. 2011;69(2):418-22. https://doi.org/10.1002/ana.22312
• 4 Zhang B, Shen C, Bealmear B, Ragheb S, Xiong WC, Lewis RA. Autoantibodies to agrin in myasthenia gravis patients. PLoS One. 2014;9(3):e91816. https://doi.org/10.1371/journal.pone.0091816
• 5 Carr AS, Cardwell CR, McCarron PO, McConville J. A systematic review of population based epidemiological studies in Myasthenia Gravis. BMC Neurol 2010;10(1):46. https://doi.org/10.1186/1471-2377-10-46
• 6 Jaretzki A 3rd, Barohn RJ, Ernstoff RM, Kaminski HJ, Keesey JC, Penn AS et al. Myasthenia gravis: recommendations for clinical research standards. Neurology. 2000;55(1):16-23. https://doi.org/10.1212/WNL.55.1.16
• 7 Benatar M, Sanders DB, Burns TM, Cutter GR, Guptill JT, Baggi F et al. Recommendations for Myasthenia Gravis Clinical Trials. Muscle Nerve. 2012;45(6);6:909-17. https://doi.org/10.1002/mus.23330
• 8 Besinger UA, Toyka KV, Hömberg M, Heininger K, Hohlfeld R, Fateh-Moghadam A Myasthenia gravis: long-term correlation of binding and bungarotoxin blocking antibodies against acetylcholine receptors with changes in disease severity. Neurology. 1983;33(10):1316-21. https://doi.org/10.1212/WNL.33.10.1316
• 9 Tindall RS, Rollins JA, Phillips JT, Greenlee RG, Wells L, Belendiuk G. Preliminary results of a doubleblind, randomized, placebo-controlled trial of cyclosporine in myasthenia gravis. N Engl J Med. 1987;316(12):719-24. https://doi.org/10.1056/NEJM198703193161205
• 10 Tindall RS, Phillips JT, Rollins JA, Wells L, Hall K. A clinical therapeutic trial of cyclosporine in myasthenia gravis. Ann N Y Acad Sci. 1993;681 Myasthenia Gr:539-51. https://doi.org/10.1111/j.1749-6632.1993.tb22937.x
• 11 Barohn RJ, McIntire D, Herbelin L, Wolfe GI, Nations S, Bryan WW. Reliability testing of the quantitative myasthenia gravis score. Ann NY Acad Sci. 1998;13(841):769-2. https://doi.org/10.1111/j.1749-6632.1998.tb11015.x
• 12 Sharshar T, Chevret S, Mazighi M, Chillet P, Huberfeld G, Berreotta C et al. Validity and reliability of two muscle strength scores commonly used as endpoints in assessing treatment of myasthenia gravis. J Neurol. 2000;247(4):286-90. https://doi.org/10.1007/s004150050585
• 13 Bedlack RS, Simel DL, Bosworth H, Samsa G, Tucker-Lipscomb B, Sanders DB. Quantitative myasthenia gravis score: assessment of responsiveness and longitudinal validity. Neurology. 2005;64(11):1968-70. https://doi.org/10.1212/01.WNL.0000163988.28892.79
• 14 Oliveira EF, Urbano JJ, Santos IR, et al. Brazilian translation, crosscultural adaptation and validation of the MG composite scale and quantitative myasthenia gravis testing form: a multicentric study protocol. Man Ther Posturology Rehabil J. 2016;14:1-5. https://doi.org/10.17784/mtprehabjournal.2016.14.342
• 15 Guillemin F, Bombardier C, Beaton D. Cross-cultural adaptation of health-related quality of life measures: literature review and proposed guidelines. J Clin Epidemiol.1993;46 (12):1417-32. https://doi.org/10.1016/0895-4356(93)90142-N
• 16 Guillemin F. Cross-cultural adaptation and validation of health status measures. Scand J Rheumatol. 1995;24(2):61-3. https://doi.org/10.3109/03009749509099285
• 17 Oliveira EF, Lima VC, Perez EA, Polaro MN, Valério BC, Pereiro JR et al. Brazilian-Portuguese translation, cross-cultural adaptation and validation of myasthenia gravis composite scale: a multicentric study. Arq Neuropsiquiatr. 2016;74(11):914-20. https://doi.org/10.1590/0004-282x20160129
• 18 Mourão AM, Araújo CM, Barbosa LSM, Gomez RS, Burns TM, Lemos SMA et al. Brazilian cross-cultural translation and adaptation of the’Questionnaire of Life Quality Specific for Myasthenia Gravis - 15 items’. Arq Neuropsiquiatr. 2013;71(12):955-8. https://doi.org/10.1590/0004-282X20130180
• 19 Sadjadi R, Conaway M, Cutter G, Sanders DB, Burns TM. Psychometric evaluation of the myasthenia gravis composite using Rasch analysis. Muscle Nerve. 2012;45(6):820-5. https://doi.org/10.1002/mus.23260
• 20 Burns TM, Conaway MR, Cutter GR, Sanders DB. Construction of an efficient evaluative instrument for Myasthenia gravis: the MG composite. Muscle Nerve. 2008;38(6):1553-62. https://doi.org/10.1002/mus.21185
• 21 Burns TM, Grouse CK, Conaway MR, Sanders DB. Construct and concurrent validation of the MG-QOL15 in the practice setting. Muscle Nerve. 2010;41(2):219-26. https://doi.org/10.1002/mus.21609
• 22 Pereira CAC. Diretrizes para testes de função pulmonar. J Pneumol. 2002;28(supl 3):S1-82.
• 23 Figueiredo IM, Sampaio RF, Mancini MC, Silva FCM, Souza MAP. Test of grip strength using the Jamar dynamometer. Acta Fisiatr. 2007;14(2):104-10. https://doi.org/10.5935/0104-7795.20070002
• 24 Barnett C, Katzberg H, Nabavi M, Bril V. The quantitative myasthenia gravis score: comparison with clinical, electrophysiological, and laboratory markers. J Clin Neuromuscul Dis. 2012;13(4):201-5. https://doi.org/10.1097/CND.0b013e31824619d5
• 25 Barnett TC, Bril V, Davis AM. Performance of individual items of the quantitative myasthenia gravis score. Neuromuscul Disord. 2013;23(5):413-7. https://doi.org/10.1016/j.nmd.2013.02.008