1. US Food and Drug Administration. Guidance for industry: qualification process for drug development tools. http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM230597.pdf. Published January 2014. Accessed March 2, 2014.
2. US Food and Drug Administration. Guidance for industry: patient-reported outcome measures. Use in medical product development to support labeling claims development tools. http://www.fda.gov/downloads/Drugs/GuidanceComplianceRegulatoryInformation/Guidances/UCM193282.pdf. Published December 2009. Accessed May 30, 2013.
3. US Food and Drug Administration. Clinical outcome assessment qualification program. http://www.fda.gov/Drugs/DevelopmentApprovalProcess/DrugDevelopmentToolsQualificationProgram/ucm284077.htm. Accessed March 2, 2014.
4. US Food and Drug Administration. Critical Path Initiative. http://www.fda.gov/ScienceResearch/SpecialTopics/CriticalPathInitiative/default.htm. Accessed March 2, 2014.
5. Coons SJ, Kothari S, Monz BU, Burke LB. The Patient-Reported Outcome (PRO) Consortium: filling measurement gaps for PRO endpoints to support labeling claims Clin Pharmaco Ther. 2011;90:743–748.