Probe tube placement is an important skill audiologists must learn to make real-ear measurements in an audiology clinic. With current evidence-based guidelines recommending insertion of the probe tube within 5 mm of the tympanic membrane (TM) for proper acoustical measurements, students must be well trained to ensure they are capable to perform this placement in clinical practice. This is not always the case as it has been found that real-ear measurements are not performed in a clinic as often as required. To address this, a simulator consisting of a 3D-printed ear model and an optical tracking system was developed to provide a training system for students to practice probe tube placement and to provide a method to evaluate competency before starting clinical practicum placements. Two simulators were developed, an adult model and a pediatric model.
To assess the face and content validity of the two probe tube placement simulators (adult and pediatric) and define barriers and facilitators to implementing this system into an educational setting.
Participants followed the setup and operating instructions designed to guide them through each functionality of the simulator. A questionnaire was used to assess face and content validity, applicability to an educational setting, and to determine perceived barriers and facilitators to using the probe tube simulators for training purposes. Five additional probe tube placements with each simulator were performed in which distance-to-TM was recorded.
Twelve participants with significant probe tube placement experience.
Participants rated each question in the questionnaire from 0% to 100% depending on their level of agreement. Averages and standard deviations (SDs) were compiled and presented for each section (face validity, content validity, and applicability to an educational setting). Final facilitators and barriers for the simulator were compiled and the top answers of each are presented. The five quantitative probe tube placement measurements for each participant were averaged, SDs were calculated, and contacts with the TM while placing the probe tube were recorded.
The average face validity score over all questions for the adult model was 65% (SD = 18.2) whereas the pediatric model received a score of 64% (16.4). The overall content validity average score was 78.7% (17) and applicability to an educational setting had an average score of 80% (5.33). The average distance-to-TM across all trials and participants was 3.74 mm (1.82) for the adult model and 2.77 mm (0.94) for the pediatric model with only one participant exceeding the recommended maximum of 5 mm. Listed shortcomings of the current simulator included realism of the 3D-printed ear, ease of insertion of an otoscope tip into the ear, ability to visualize the ear canal "landmarks" and the TM, and foam tip insertion experience.
Results were generally very positive for the simulator, and future iterations will look to improve the flexibility and texture of the ear, as well as the otoscopic view of the ear canal and TM.