Development and validation of a new questionnaire measuring treatment satisfaction in patients with non-valvular atrial fibrillation: SAFUCA®.

OBJECTIVE: To develop a new questionnaire with good psychometric properties to measure satisfaction with medical care in patients with non-valvular atrial fibrillation. METHOD: The initial instrument was composed of 37 items, arranged in 6 dimensions: efficacy, ease and convenience, impact on daily activities, satisfaction with medical care, undesired effects of medication, and overall satisfaction. Items and dimensions were extracted from reviewing existing instruments, 3 focus groups with chronic patients, and a panel of 8 experts. Additionally, 3 visual analog scales measuring quality of life, effectiveness, and overall satisfaction were administered. A convenience sample of 119 patients was used for item reduction. Classic psychometric theory and item analysis techniques were used (exploratory factor and confirmatory factor analysis, test-retest, and correlation with visual scales). A validation sample of 230 patients was used to assess convergent validity, and an additional 220 patients sample was used to discriminate between treatment and compliance groups. RESULTS: The questionnaire was reduced in length to 25 items, but the impact dimension had split in treatment inconvenience and treatment control. Overall reliability was high (α = 0.861) with acceptable dimensional reliabilities (α = 0.764-0.908). Individual dimensions correlated to varying degrees. Test-retest correlations were high (r = 0.784-0.965), and correlations with visual and already validated scales were substantial. Differences were detected between antivitamin K and new-oral-anticoagulant treatments in several dimensions (p < 0.05). Treatment satisfaction was related with compliance. CONCLUSION: This new 25-item questionnaire has good psychometric properties for measuring satisfaction with medical care in patients with this condition. It is capable of detecting differences between different treatments.