Cost-effectiveness evaluations of interventions to prevent or treat spin a bifida require quality of life information measured as preference scores. Preference scores of care givers also may be relevant. This study tested whether the preference scores of children with spin a bifida and their care givers would decrease as disability in the child increased. Families of children aged 0–17 with spin a bifida (N=98) were iden ti fied using a birth defect surveillance sys tem in the state of Arkansas. Primary care giv ers of chil dren with spin a bifida identified other families with an unaffected child (N=49). Preference scores for child health states were determined using the Health Utilities Index – Mark 2 (HUI2). Care giver preference scores were determined using the Quality of Well-Being (QWB) scale. Children with spin a bifida were categorized into three disability levels according to the location of the childs lesion. Mean preference scores declined for both affected children and the primary care giver as disability in the child increased. In multivariate analysis, the preference score of the child was a significant and positive predictor of the primary care givers preference score. A more modest association was found for care giver health preference scores by lesion location. The findings can inform cost-effec tiveness evaluations of interventions to treat or prevent spin a bifida.