Development of two instruments measuring social support for siblings of children with cancer

The literature on childhood cancer provides a very limited understanding of healthy siblings' perceptions of supportive interventions during the childhood cancer experience. The purpose of this article is to discuss the development of the Nurse-Sibling Social Support Questionnaire (NSSSQ). Instrument methodology for the study involved item development, face and content validation, and internal consistency reliability as described by Hockenberry-Eaton, Manteuffel, and Bottomley (1997). Item development for the research instrument evolved from an extensive review of the literature and clinical experience of the principal investigator. Content validity of the instrument was accomplished by five experienced pediatric oncology nurses according to the methodology described by Lynn (1986). Using the content validity index, each nurse rated each item as either 4 or 5, indicating 100% agreement among experts that these items measured the concept of social support. Readability for the instrument was determined by using a computerized program. Results showed that readability was concordant with the grade school level for all items. Twenty-five school-age siblings of children with cancer and their mothers were asked to complete the questionnaire. Instrument completion was accomplished in less than 1 hour. The NSSSQ showed high internal consistencies (alpha coefficients >.90). Results indicated that siblings' perceptions of social support differed from those of their mothers. Siblings perceive emotional and instrumental support as greater in importance, whereas mothers perceive emotional and informational support as more beneficial to siblings. Support issues for siblings of children with cancer have been difficult to assess because of the lack of appropriate instruments. This study finding provides exploratory evidence to suggest that the new instrument can help measure siblings' perceptions of social support during the childhood cancer experience.