['Array comparative genomic hybridization is an emerging test used clinically to identify the etiology of children with developmental delay, yet little data are available regarding how physicians use these results. This pilot study evaluated how positive test results were used to influence patient management.', 'We surveyed 14 physicians of 48 patients who had copy number changes detected by microarray technology.', "Of 48 patients, 34 (70.8%) had 65 management changes after receiving the test result (with individual patients having 1-3 changes). Most commonly, physicians provided patients' families with a recurrence risk for affected subsequent pregnancies (35% of patients). Patients avoided other forms of testing (35%) and had improved access to services (25%). In 27% of patients, physicians altered medical management by referring patients to a specialist or recommending medical screening. Patients with known syndromes had multiple changes, but patients with novel copy number changes also had recommendations made based on the array result."] Do how physicians use array comparative genomic hybridization results to guide patient management in children with developmental delay?