Risk factors for amblyopia in the vision in preschoolers study.

Objective: To evaluate risk factors for unilateral amblyopia and for bilateral amblyopia in the Vision in Preschoolers (VIP) study.

Design: Multicenter, cross-sectional study.

Participants: Three- to 5-year-old Head Start preschoolers from 5 clinical centers, overrepresenting children with vision disorders.