C o p y r i g h t I n f o r m a U K L i m i t e d 2 0 0 8 N o t f o r S a l e o r C o m e r c i a l D i s t r i b u t i o n U n a u t h o r i z e d u s e p r o h i b i t e d . A u t h o r i s e d u s e r s c a n d o w n l o a d , A B S T R A C TObjective: Development of an instrument for characterization of symptom patterns and severity in patients with cryopyrin-associated periodic syndromes (CAPS). Methods: Two generations of daily health assessment forms (DHAFs) were evaluated in this study. The first-generation DHAF queried 11 symptoms. Analyses of results obtained with that instrument identified five symptoms included in a revised second-generation DHAF that was tested for internal consistency and test-retest reliability. This DHAF was also assessed during the initial portion of a phase 3 clinical study of CAPS treatment.Results: Forty-eight CAPS patients provided data for the first-generation DHAFs. Five symptoms (rash, fever, joint pain, eye redness/pain, and fatigue) were included in the revised second-generation DHAF. Symptom severity was highly variable during all study phases with as many as 89% of patients reporting at least one symptom flare, and percentages of days with flares reaching 58% during evaluation of the second-generation instrument. Mean composite key symptom scores (KSSs) computed during evaluation of the second-generation DHAF correlated well with Physician's Global Assessment of Disease Activity (r ¼ 0.91, p50.0001) and patient reports of limitations of daily activities (r ¼ 0.68, p50.0001). Test-retest reliability and Cronbach's 's were high (0.93 and 0.94, respectively) for the second-generation DHAF. Further evaluation of this DHAF during a baseline period and placebo treatment in a phase 3 clinical study of CAPS patients indicated strong correlations between baseline KSS and Physician's Global Assessment of Disease Activity. Cronbach's 's at baseline and test-retest reliability were also high. Potentially important study limitations include small sample size, the lack of a standard tool for CAPS symptom assessment against which to validate the DHAF, and no assessment of the instrument's responsivity to CAPS therapy.Conclusions: The DHAF is a new instrument that may be useful for capturing symptom patterns and severity in CAPS patients and monitoring responses to therapies for these conditions.