Measuring self-care independence in children with cystic fibrosis: the Self-Care Independence Scale (SCIS)

Abstract

We describe the development and psychometric properties of a survey tool designed to evaluate children's level of independence in their cystic fibrosis (CF) treatment. Children's self-care autonomy is important to measure and may have a direct effect on children's active involvement in their treatment and their adherence. Existing instruments that evaluate children's independence in their CF treatment fail to yield practical information that can help research and patient management. The Self-Care Independence Scale (SCIS) is a 44-item questionnaire that is completed by parents. The SCIS was completed by the parents of 76 patients with CF (ages 4-17 years). Youths completed two structured interviews, which screened patients for average or higher cognitive functioning (an inclusion criterion) and measured their CF treatment knowledge. Parents completed two other self-report questionnaires. Results indicated that the SCIS has acceptable internal consistency and good test-retest reliability. The construct validity of the SCIS was supported by positive correlations between patient age, number of years since diagnosis, and SCIS total scores. The concurrent validity of the SCIS was supported by correlations between a measure of nonillness-specific dependence and a measure of patient self-care knowledge. Children's SCIS total scores per age group are presented. This study supports the SCIS as a psychometrically sound measure of self-care independence in CF. This measure has several uses. For example, the SCIS may be a screening tool for adolescents who are preparing to transition to adult CF centers and who will need to assume more independence in their self-care. The SCIS may also be used to evaluate educational programs that promote self-care knowledge and skill in children with CF.