Italy / Humans / Fibromyalgia / Female / Male / Differential Diagnosis / ROC Curve / Psoriatic Arthritis / Middle Aged / Adult / Internal medicine Doppler ultrasonography / Musculoskeletal system / Chi Square Distribution / Sensitivity and Specificity / Pilot Projects / Predictive value of tests / Differential Diagnosis / ROC Curve / Psoriatic Arthritis / Middle Aged / Adult / Internal medicine Doppler ultrasonography / Musculoskeletal system / Chi Square Distribution / Sensitivity and Specificity / Pilot Projects / Predictive value of tests