1. CMS. Hospital outpatient quality reporting (OQR) specifications manual. V6.0b. Available at: http://qualitynet.org/dcs/ContentServer?c=Page&pagename=QnetPublic%2FPage%2FQnetTier2&cid=1196289981244. Accessed May 14, 2014.
2. QualityNet. Imaging efficiency measures. Available at: http://qualitynet.org/dcs/ContentServer?c=Page&pagename=QnetPublic%2FPage%2FQnetTier2&cid=1228695266120. Accessed April 27, 2014.
3. Agency for Healthcare Research and Quality. NQF-endorsed measure. Imaging efficiency: percentage of abdomen CT studies that are performed with and without contrast out of all abdomen CT studies performed. Available at: http://www.qualitymeasures.ahrq.gov/content.aspx?id=34198. Accessed April 27, 2014.
4. QualityNet. OP-14: simultaneous use of brain CT and sinus CT. Available at: https://www.qualitynet.org/dcs/BlobServer?blobkey=id&blobnocache=true&blobwhere=1228889985173&blobheader=multipart%2Foctet-stream&blobheadername1=Content-Disposition&blobheadervalue1=attachment%3Bfilename%3DOP-14_Technical_Specif_030813.pdf&blobcol=urldata&blobtable=MungoBlobs. Accessed April 27, 2014.
5. Agency for Healthcare Research and Quality. NQF-endorsed measure. Imaging efficiency: ratio of thorax CT studies that are performed with and without contrast out of all thorax CT studies performed. Available at: http://www.qualitymeasures.ahrq.gov/content.aspx?id=34199. Accessed April 27, 2014.