Evaluating Medical Devices Remotely: Current Methods and Potential Innovations.

OBJECTIVE: We present examples of laboratory and remote studies, with a focus on studies appropriate for medical device design and evaluation. From this review and description of extant options for remote testing, we provide methods and tools to achieve research goals remotely. BACKGROUND: The FDA mandates human factors evaluation of medical devices. Studies show similarities and differences in results collected in laboratories compared to data collected remotely in non-laboratory settings. Remote studies show promise, though many of these are behavioral studies related to cognitive or experimental psychology. Remote usability studies are rare but increasing, as technologies allow for synchronous and asynchronous data collection. METHOD: We reviewed methods of remote evaluation of medical devices, from testing labels and instruction to usability testing and simulated use. Each method was coded for the attributes (e.g., supported media) that need consideration in usability studies. RESULTS: We present examples of how published usability studies of medical devices could be moved to remote data collection. We also present novel systems for creating such tests, such as the use of 3D printed or virtual prototypes. Finally, we advise on targeted participant recruitment. CONCLUSION: Remote testing will bring opportunities and challenges to the field of medical device testing. Current methods are adequate for most purposes, excepting the validation of Class III devices. APPLICATION: The tools we provide enable the remote evaluation of medical devices. Evaluations have specific research goals, and our framework of attributes helps to select or combine tools for valid testing of medical devices.

Cationic lipids percentage and processing temperature are critical in designing siRNA lipid nanoparticles.

To design a clinically viable small interfering RNA (siRNA) formulation, it is essential to understand the in vivo siRNA delivery mechanism during the product development. However, majority of reported siRNA delivery studies are based on testing only isolated factors, with ambiguous interpretation of often in vitro transfection results. Correlating physicochemical properties with in vivo transfection efficiency thus represents an important step towards rational design of siRNA delivery systems. In this study, design of experiments studies were applied to probe formulation attributes and process parameters, with in vivo activities evaluated as a primary response along with physicochemical properties. Statistical analysis was performed to identify the significance of each input factor towards the in vivo transfection efficiency using a Positive Readout System. The interactions between these factors were also analyzed. Our results indicated that among the formulation factors evaluated, the percentage of cationic lipid is of most significant effect. During the process, temperature stands out as the most significant factor impacting the in vivo activities. These results shed light on our design of siRNA lipid nanoparticle formulations in the early development stage.