The caregivers of 61 eligible children (6 months to 12 years old) completed a 20-item (OSA-20) health-related quality-of-life survey after polysomnography was performed to psychometrically validate the OSA-20. Excellent test-retest reliability was obtained for the individual survey items (R>0.74). Construct validity was shown by significant correlation of the mean survey score with the respiratory distress index (R = 0.43) and adenoid size (R = 0.43). Two items with poor validity were dropped, reducing the survey to 18 items (OSA-18). The relationship between the OSA-18 summary score and respiratory distress index remained significant when adjusted for tonsil size, adenoid size, body mass index, and child age. On the basis of the total survey score, the impact of OSAS on quality of life was small for 20 children (33%), moderate for 19 (31%), and large for 22 (36%). The OSA-18 is a practical means of office-based determination of quality-of-life impact for obstructive sleep apnea syndrome in children.