IMPORTANCE Adolescent idiopathic scoliosis, a lateral curvature of the spine of unknown cause with a Cobb angle of at least 10°, occurs in children and adolescents aged 10 to 18 years. Idiopathic scoliosis is the most common form and usually worsens during adolescence before skeletal maturity. Severe spinal curvature may be associated with adverse long-term health outcomes (eg, pulmonary disorders, disability, back pain, psychological effects, cosmetic issues, and reduced quality of life). Early identification and effective treatment of mild scoliosis could slow or stop curvature progression before skeletal maturity, thereby improving long-term outcomes in adulthood. OBJECTIVE To update the 2004 US Preventive Services Task Force (USPSTF) recommendation on screening for idiopathic scoliosis in asymptomatic adolescents. EVIDENCE REVIEW The USPSTF reviewed the evidence on the benefits and harms of screening for and treatment of adolescent idiopathic scoliosis. FINDINGS The USPSTF found no direct evidence on screening for adolescent idiopathic scoliosis and health outcomes and no evidence on the harms of screening. The USPSTF found inadequate evidence on treatment with exercise and surgery. It found adequate evidence that treatment with bracing may slow curvature progression in adolescents with mild or moderate curvature severity (Cobb angle <40° to 50°); however, evidence on the association between reduction in spinal curvature in adolescence and long-term health outcomes in adulthood is inadequate. The USPSTF found inadequate evidence on the harms of treatment. Therefore, the USPSTF concludes that the current evidence is insufficient and that the balance of benefits and harms of screening for adolescent idiopathic scoliosis cannot be determined. CONCLUSIONS AND RECOMMENDATION The USPSTF concludes that the current evidence is insufficient to assess the balance of benefits and harms of screening for adolescent idiopathic scoliosis in children and adolescents aged 10 to 18 years. (I statement).