1. Congress of the United States Congressional Budget Office. Research on the comparative effectiveness of medical treatments: issues and options for an expanded federal role. 2007. http://www.cbo.gov/sites/default/files/12-18-comparativeeffectiveness.pdf . Accessed 5 May 2014.
2. Fairbrother G, O’Brien E, Pradhananga R, Chalkidou K. Improving quality and efficiency in health care through comparative effectiveness analyses: an international perspective. 2014. http://www.academyhealth.org/files/publications/2014CERImprovingQuality.pdf . Accessed 3 June 2015.
3. Goodman CS. Introduction to health technology assessment. Bethesda, MD: National Library of Medicine (US). 2014. http://www.nlm.nih.gov/nichsr/hta101/HTA_101_FINAL_7-23-14.pdf . Accessed 12 June 2015.
4. Kernick D. An introduction to the basic principles of health economics for those involved in the development and delivery of headache care. Cephalalgia. 2005;25(9):709–14.
5. U.S. Congress, Office of Technology Assessment. Protecting Privacy in Computerized Medical Information, OTA-TCT-576. Washington, DC: U.S. Government Printing Office, 1993.