Objective: To validate a translated Italian version of the Fibrofatigue Scale (FFS).
Methods: The Italian version of FFS was administered to 60 patients affected by fibromyalgia (FM) (57 patients were interviewed again 10 days later) together with the Italian version of the Fibromyalgia Impact Questionnaire (FIQ), the Stanford Health Assessment Questionnaire (HAQ) and the Medical Outcome Survey Short Form-36 (SF-36). All patients were asked about the severity of pain today (10-cm visual analogue scale) and the duration of symptoms. Test-retest reliability was assessed using Spearman correlations. Internal consistency was evaluated with Cronbach's alpha of reliability. Construct validity of the FFS was evaluated by correlations among the FFS, the FIQ and the subscales of the SF-36.
Results: Mean duration of symptoms was 7.6 years, and mean age of participants was 56.3 years. Test-retest reliability was between 0.70 and 0.95 for the single items as well as for the total FFS and other components. Internal consistency was 0.90 for the overall FFS. Significant correlations were obtained between the FFS items and the SF-36.
Conclusions: The Italian FFS is a reliable and valid instrument for detecting and measuring functional disability and symptoms severity in Italian patients with FM.