Recommendations for additional imaging in radiology reports: multifactorial analysis of 5.9 million examinations.

Purpose: To quantify the rates of recommendation for additional imaging (RAI) in a large number of radiology reports of different modalities and to estimate the effects of 11 clinically relevant factors.

Materials And Methods: This HIPAA compliant research was approved by the institutional review board under an expedited protocol for analyzing anonymous aggregated radiology data. All diagnostic imaging examinations (n = 5 948 342) interpreted by radiologists between 1995 and 2008 were studied.