Clinical and analytical considerations in the study of health status in device trials for heart failure

Measures of health status (including symptoms, functional status, or quality of life) assess patients' experiences of their disease, and may therefore be used to quantify the benefits and risks of treatment. The aim of this article is to provide recommendations to regulatory agencies and research sponsors regarding the use of health status measures in medical device trials.

A workshop jointly planned by the Heart Failure Society of America and the US Food and Drug Administration was convened in October 2003 in Washington, DC. A Working Group to address health status measures initiated its collaboration at the workshop and continued its efforts throughout the next year. The Working Group recommended assessment of health status in all studies of heart failure therapy. Standardized instruments known to be valid, reliable, responsive to changes, and available in the languages of target populations should be used. Minimizing bias may be accomplished by using blinded, independent evaluators; collecting multiple health status measures; using valid statistical methods; and creating a health status resource bank.

Assessment of health status should be part of any device trial and should occur regardless of whether the device is intended as destination or bridging therapy. Health status endpoints should be chosen, collected, and analyzed with the same level of scientific rigor as traditional clinical endpoints. Regulatory agencies should require use of analytic methods that handle the complexity of health status data in addition to usual protocol protections.