Potentially useful outcome measures for clinical research in pediatric neurosurgery

The choice of outcome (or outcomes) and their measurement are critical for a sound clinical trial. Surgeons have traditionally measured simple outcomes such as death, duration of survival, or tumor recurrence but have recently developed more sophisticated measures of the effect of an intervention. Many outcome measures require a lengthy maturation process, which includes a determination of the instrument's validity, reliability, and sensitivity; thus, using established instruments rather than creating new ones is recommended. The authors illustrate several guidelines for the determination of appropriate outcome measures by using examples from their experience and describe several outcome measures that can be used in pediatric neurosurgery. These include general outcome measures such as the Pediatric Evaluation of Disability Inventory and the Functional Independence Measure for Children, which measure physical function and independence in chronically ill and disabled children as well as disease-specific measures for hydrocephalus (Hydrocephalus Outcome Questionnaire), cerebral palsy (gross motor function and performance measures), head injury (Pediatric Cerebral Performance Category and Children's Coma Scale), and oncology (Pediatric Cancer Quality-of-Life Inventory).