... scales and, where applicable, an exploration of the scales obtained in our sample, based on exploratory factor analysis The aim was to simplify and reduce the number of items of each scale according ... technical support Author details Facultad de Psicolog a, Universidad Nacional de Educación a Distancia, Madrid, Spain 2Unidad de Reumatolog a, Instituto Provincial de Vallejo et al Health and Quality ... Garc a- Campayo J, Pascual A, Alda M, Marzo J, Magallón R, Fortes S: The Spanish version of the fibrofatigue scales: validation of a questionnaire for the observer’s assessment of fibromyalgia...