Assessing Bias in Clinical Trials of Medical Devices

• Activity Number: 393
• Type: Topic Contributed
• Date/Time: Tuesday, July 31, 2012 : 2:00 PM to 3:50 PM
• Sponsor: Biopharmaceutical Section
• Author(s): Alvin Van Orden*+
• Companies: FDA/CDRH
• Keywords: Blinding ; Medical Devices ; Bias ; Clinical Trials

Abstract

Blinding is an essential part in establishing the quality of evidence presented in clinical trials of medical devices. It prevents biases caused by the knowledge of treatment assignment among study subjects, investigators, as well as outcome evaluators. It also maintains the compliance and retention of the study subjects. Doubts are often raised if the subject can feel the device working or if the adverse events hint the subject as to the treatment being received. Therefore, an appropriate assessments can provide valuable support evidence of successful blinding to ease concerns when the study results are interpreted. In this presentation, we will discuss some general regulatory considerations about designing, implementing and assessing blinding in medical device studies. Then, we will present a case study where the blinding assessment established the effectiveness of the masking. In a trial where the effectiveness of the device was marginal, it was important to establish that the small effect was not a product of the lack of blinding.