Reliability and validity of a self-efficacy instrument specific to sickle cell disease

The psychometric properties of a new, 9-item scale measuring disease- specific perceptions of self-efficacy were investigated in a community-based sample of adults (N = 83) with sickle cell disease (SCD). The Sickle Cell Self-Efficacy Scale (SCSES) was comprised of nine questions relating to participants' perceptions of their ability to function on a day-to-day basis and to manage SCD symptomatology (e.g. episodes of pain). The SCSES demonstrated good internal consistency, discriminant validity, and convergent and predictive validity, both with previously validated measures of related constructs as well as with reported SCD symptomatology. Overall, the instrument appears to be reliable and valid for assessing clients' self- efficacy for engaging successfully in day-to-day activities despite having SCD. Future investigators may wish to examine temporal and causal links between alterations in self-efficacy and changes in adjustment to sickle cell disease; the SCSES provides a psychometrically sound tool with which to investigate these phenomena. (C) 2000 Elsevier Science Ltd.