 Hi everyone. My name is Megan Knitzer. I am honored to present my research to you today and I hope you will enjoy this presentation. This presentation will focus on sound level monitoring earphones with smartphone feedback as an intervention to promote healthy listening behaviors in young adults. Myself, Professor David Swannable, Dr. Faima Malamat-Ashmal and Professor Venayam were part of this research team. Historically, the focus of noise-induced hearing loss has largely been related to occupational noise exposure and to hearing loss in the elderly arising from lifelong exposure to noise. With the increased use of personal audio systems, recreational noise-induced hearing loss has become a major public health concern, especially among adolescents and young adults. The World Health Organization estimates that more than a billion adolescents and young adults are at risk of acquiring recreational noise-induced hearing loss due to the unsafe use of personal audio systems. Among the younger generation, aged 12 to 35 years, approximately 50 percent are exposed to dangerous sound levels due to their personal audio systems. Although recreational noise-induced hearing loss is a totally preventable condition, it still remains a challenge to persuade young people to adopt safe listening habits. Educational programs alone have not been effective in changing listening behavior in personal audio system users. What may be more effective is an intervention that does not only consist of information, but also provides individuals with tangible cues. The use of technology is a promising development in hearing health intervention. Technology-based interventions offer the opportunity to reach larger audiences in cost-effective ways. New technologies such as DbTrack, which was used in this study, allow users to monitor personal sound exposure on their own devices by using sound-level monitoring earphones with an accompanying smartphone application. The DbTrack Western sound-level monitoring earphones on noise-canceling earphones was built in microphones to measure in-ear sound exposure. The accompanying DbTrack smartphone application records listening activity measured by the earphones, in other words, listening duration and listening intensity, and calculates an accurate sound dose on a daily and weekly basis. The app team provides real-time feedback based on listening behaviors, for example, notifications of intensity levels, volume warnings, remaining safe listening time, daily and weekly sound dosages, and sound dose warnings. The sound exposure limits of the DbTrack application are based on the World Health Organization and international telecommunication union standard for safe listening devices and systems. Prior to the Who ITU standard, there were no established standards specifically for the use of personal audio systems. The Who ITU standard is more conservative in terms of sound allowance when compared to many other standards established for occupational noise exposure. This study was conducted in two phases. Phase one aimed to determine the accuracy and the reliability of the DbTrack We Stone sound-level monitoring earphones, and phase two aimed to determine the effect of sound-level monitoring earphones with smartphone feedback and hearing health information as an intervention to promote healthy listening behaviors in young adults. In both phases of the study, the in-ear microphone of each pair of earphones was calibrated using a DbTrack Calibrator. In phase one experiment one, the accuracy and intra-device reliability of the earphones were determined by conducting repeated measures using seven pairs of sound-level monitoring earphones as well as an occluded ear simulator coupler with a sound-level meter. In experiment two, the within-subject reliability of the earphones was determined by comparing the in-ear sound levels of 19 participants measured by the earphones during test-free test conditions. The second phase of the study was conducted using a single-group pretest post-test design. Forty young adults reported high sound exposure through their personal audio systems participated in the study. Participants completed an online survey regarding sound exposure through personal audio systems. Thereafter, they were required to use the sound-level monitoring earphones and customized version of the DbTrack app for four weeks. During the first two weeks, the participants' in-ear sound levels were measured by the earphones and recorded in the application with the application's smartphone feedback feature being disabled. This was the pretest condition. The application monitored all audio output from the device via the earphones including music, videos and games. The DbTrack app synced the recorded listening behaviors to the participants' profiles on the secure DbTrack cloud-based portal. I used this tool to monitor each participants' listening activity and to identify possible singing problems. At the end of the first two weeks, a brief information guide on hearing health was provided electronically to the participants. During the last two weeks, the smartphone feedback was automatically enabled on the application which allowed the participants to monitor the listening activity. This was the post-test condition. Participants completed a second online survey with questions regarding feedback on the study. Results of phase one experiment one showed that the maximum LQ difference between the earphones and SLM was less than one DbZ for both the test and retest conditions. The maximum LQ difference between repeated measures across earphones was also less than one DbZ. Nineteen young adults participated in experiment two of phase one of the study including 10 females and nine males between 20 and 35 years of age. Results showed that the mean LQ difference between repeated measures across participants was less than 0.6 Dba and the maximum difference was less than 1.4 Dba. The sound label monitoring earphones were therefore well within the recommended American National Institute standard for personal noise dosing meters of plus minus two Db when compared to a reference measurement and when compared to each other. Forty young adults including 25 males and 15 females between 18 and 35 years of age participated in phase two of the study. The survey regarding sound exposure through personal audio systems revealed that two-thirds of participants were motivated or very motivated to develop safe listening behaviors. There was a statistically significant decrease in the average daily intensity and sound dose measured by the earphones during pre-test and post-test conditions with a small and medium effect size respectively. Sound dose was the most important variable in which we needed to see change and we were pleased to see that the intervention had the largest effect on sound dose out of all three variables based on the effect size calculations. The post-study survey revealed that smartphone feedback and hearing health information motivated 95 percent of participants to change their listening behavior. 90 percent of participants reported that the smartphone feedback contributed the most. In conclusion this study has large implications. Currently we do not know of any public health intervention that can help prevent young adults from acquiring a recreational noise induced hearing loss through their personal audio systems. It was also the first study to investigate the effect of sound level monitoring earphones with smartphone feedback and hearing health information on listening behaviors in young adults. The study's preliminary data indicate that DB Track Western sound level monitoring earphones with a calibrated in-ear microphone can reliably and accurately measure personal audio systems sound exposure. Feedback on sound exposure using accurate sound level monitoring earphones with an accompanying application can potentially promote safe listening behavior in young adults and reduce the risk of acquiring a recreational noise induced hearing loss. The main study limitations was the small sample size and the high variability in results. Possible sampling bias since non-probability sampling was used. Real ear measurements could have been conducted in addition to the real ear coupler measurements. And then most of the data collection for phase 2 of the study took place during COVID-19 pandemic and lockdown period. This affected participants' daily routines as well as their listening behaviors. And the study was terminated earlier due to the pandemic allow a smaller sample size than initially anticipated. This may explain small effect sizes or marginal significance. Participants with high sound dose percentages received multiple notifications from the application during the post-discondition, which they might have become accustomed to over time. Only Android technology was used in the study, which does not allow for the device's internal compresses to be switched off. So although the audio route with the least processing was used, this might have contributed to the high variability of results between participants. This research should be expanded using a larger sample over a longer period of time, as it might decrease variability among participants and lessen the impact of internal and external factors on listening behaviors. A longer study period can be used to determine whether the effects of the intervention are sustained and including samples of different ages, especially teen ages, could inform preventative strategies in this group. Furthermore, notifications delivered by the application could be tailored by means of altering the frequency of notifications to prevent users from becoming disinterested in the application's feedback. Thank you for listening. This research has been published in ear and hearing for those who are interested to give it a read. Feel free to ask me any questions or to send me an email.