## 4 Video Otoscope with an Integrated Scanner Prototype Validation
The first part of the questionnaire collects detailed information about the condition of the patient's outer ear, allowing audiologists and other healthcare professionals to assess the specific characteristics of the EEC and eardrum, which are essential for comparing the performance of the conventional otoscope and the new device. Analysis of the physical aspects of the ear, such as the length and diameter of the EEC and the presence of cervumen and/or foreign bodies in the EEC, or pathologies, are critical for determining the effectiveness of the otoscope in a variety of conditions. The questionnaire then consists of short closed-answer questions, which assess aspects such as the difficulty in handling the video otoscope, the ability to adjust to the curvature of the EEC, and the learning curve to identify barriers to its effective use. The authors believe that the design of a device should be guided by the needs and limitations of the end users--based on the principle of user-centered design. The questionnaire collects direct audiologist feedback, allowing for improvements based on real user experiences. The usability of a medical device is fundamental to ensuring that healthcare professionals can use it efficiently and safely without compromising the quality of care. Questions are performed to assess the efficiency of the video otoscope and explore its comfort, stability, and ease of use. These aspects include the following: (i) the fixation of the equipment in the patient's external auditory canal, (ii) the depth of insertion, and (iii) the clarity/sharpness of the image obtained, all of which determine the success of the clinical examination. The Likert scale used in the questions makes it possible to capture subjective levels of satisfaction and difficulty, translating qualitative opinions into quantitative data that can be analyzed statistically, from difficulty in handling to overall satisfaction with the equipment. These measurements are useful for identifying patterns in the user experience, allowing for iterative device validation based on empirical feedback. In addition, open questions are inserted into the questionnaire so that professionals can identify specific limitations that could be improved in the device. This qualitative information offers a more detailed view of the areas that need adjustment, whether related to ergonomics, equipment performance, or comfort during prolonged use. According to the Technology Acceptance Theory [45], perceived usefulness and ease of use are key determinants of technology adoption. Collecting criticisms and suggestions helps the researcher to align the device according to the users' expectations. The patient's perspective was also taken into account through a questionnaire using a Likert scale, where \(1\) corresponds to very dissatisfied/very difficult and \(5\) to very satisfied/very easy, whose questions focus on the new device's satisfaction, comfort, and ergonomics. The degree of satisfaction using the video otoscope compared to conventional otoscopy was also taken into account. As with the questionnaire aimed at healthcare professionals, the open questions were considered an opportunity for device optimization in future versions. In this first validation phase, \(11\) health professionals answered the questionnaire, with a minimum of one year's professional experience and a maximum of \(28\) years, with an average of \(7.9\) (SD \(\pm\) 10.08) years of experience (Figure 7). This variation in the length of professional experience was intentional to understand new professionals' adherence to the technology and, on the other hand, to see if the technology could be a barrier for professionals with more years of experience with ingrained habits of using conventional otoscopy. Each professional underwent two evaluations (right and left ear) for \(22\) experiences with the new device.