Development and initial evaluation of a measure of self-management for adults with antineutrophil cytoplasmic antibody-associated small-vessel vasculitis

Abstract

Objective
To develop a measure of illness self-management for adults living with antineutrophil cytoplasmic antibody (ANCA)–associated small-vessel vasculitis (ANCA-SVV) and to gather evidence of its reliability and validity.

Methods
Development of the Vasculitis Self-Management Scale (VSMS) was guided by previous research on self-management in other chronically ill populations, a review of the current treatment literature for ANCA-SVV, interviews with patients, and consultation with experts. A total of 205 patients living with ANCA-SVV or a closely related condition then completed the VSMS, along with measures of sociodemographic and clinical variables, social desirability bias, and general adherence to medical recommendations, using a self-administered mailed questionnaire. A principal components analysis was conducted on the VSMS items. Internal consistency reliability and construct validity of the resulting subscales were assessed. Forty-four patients completed the VSMS a second time, for the purpose of assessing test–retest reliability.

Results
Analyses suggested an 8-factor solution. The final VSMS consisted of 43 items representing these 8 behavioral domains. Correlations among the 8 domains were null to modest in magnitude. The internal consistency reliability of the 8 subscales ranged from minimally acceptable (α = 0.67) to excellent (α = 0.94), and correlations between subscale scores at time 1 and time 2 suggested good temporal stability. Preliminary evidence for validity was mixed.

Conclusion
These findings suggest that the VSMS is a promising method for assessing illness self-management in adults with ANCA-SVV. More research exploring the validity of the measure is warranted.