OBJECTIVEThe purpose of this study was to assess the frequency of pediatric CT in 40 less-resourced countries and to determine the level of appropriateness in CT use.MATERIALS AND METHODSData on the increase in the number of CT examinations during 2007 and 2009 and appropriate use of CT examinations were collected, using standard forms, from 146 CT facilities at 126 hospitals.RESULTSThe lowest frequency of pediatric CT examinations in 2009 was in European facilities (4.3%), and frequencies in Asia (12.2%) and Africa (7.8%) were twice as high. Head CT is the most common CT examination in children, amounting to nearly 75% of all pediatric CT examinations. Although regulations in many countries assign radiologists with the main responsibility of deciding whether a radiologic examination should be performed, in fact, radiologists alone were responsible for only 6.3% of situations. Written referral guidelines for imaging were not available in almost one half of the CT facilities. Appropriateness criteria for CT examinations in children did not always follow guidelines set by agencies, in particular, for patients with accidental head trauma, infants with congenital torticollis, children with possible ventriculoperitoneal shunt malfunction, and young children (< 5 years old) with acute sinusitis. In about one third of situations, nonavailability of previous images and records on previously received patient doses have the potential to lead to unnecessary examinations and radiation doses.CONCLUSIONWith increasing use of CT in children and a lack of use of appropriateness criteria, there is a strong need to implement guidelines to avoid unnecessary radiation doses to children.