Evaluating the Acceptance and Usability of an Independent, Noncommercial Search Engine for Medical Information: Cross-Sectional Questionnaire Study and User Behavior Tracking Analysis - Lisa Specht; Raphael Scheible; Martin Boeker; Erik Farin-Glattacker; Nikolas Kampel; Marina Schmölz; Andrea Schöpf-Lazzarino; Stefan Schulz; Christian Schlett; Fabian Thomczyk; Sebastian Voigt-Radloff; Constanze Wegner; et al. (JMIR Human Factors)