The psychological study of chronically ill and disabled children: are healthy siblings appropriate controls?

This study examined the appropriateness of siblings as controls in the psychological assessment of children with chronic illness or disability. Findings from 304 cases and 360 randomly selected controls were compared to findings from a subset of 206 case-sibling pairs. Cases were children 6 to 18 years of age with cystic fibrosis, cerebral palsy, myelodysplasia, and multiple handicaps, selected from specialty clinics in two teaching hospitals in the Cleveland area. Results from both data sets were in agreement on major findings indicating that children with cystic fibrosis are not at increased risk for psychopathology, whereas children in the remaining three diagnostic groups show a substantial excess in Mentation Problems and Isolation. The comparisons with matched siblings underestimated pathology in the disabled children in Regressive-Anxiety and aggressive behavior.