Contemporary and Systematic Review of Smartphone Apps for Tinnitus Management and Treatment

: Tinnitus is a complex and heterogeneous psycho-physiological disorder responsible for 1 causing a phantom ringing or buzzing sound albeit the absence of an external sound source. It 2 has a direct inﬂuence on affecting the quality of life of its sufferers. Despite being around for a 3 while, there hasn’t been a cure for tinnitus, and the usual course of action for its treatment involves 4 use of tinnitus retaining and sound therapy, or Cognitive Behavioral Therapy (CBT). One positive 5 aspect about these therapies is that they can be administered face-to-face as well as delivered via internet or smartphone. Smartphones are especially helpful as they are highly personalized devices, 7 and offer a well-established ecosystem of apps, accessible via respective marketplaces of differing 8 mobile platforms. Note that current therapeutic treatments such as CBT have shown to be effective 9 in suppressing the tinnitus symptoms when administered face-to-face, their effectiveness when 10 being delivered using smartphones is not known so far. A quick search on the prominent market 11 places of popular mobile platforms (Android and iOS) yielded roughly 250 smartphone apps offering 12 tinnitus-related therapies and tinnitus management. As this number is expected to steadily increase 13 due to high interest in smartphone app development, a contemporary review of such apps is crucial. 14 In this paper, we aim to review scientiﬁc studies validating the smartphone apps, particularly to 15 test their effectiveness in tinnitus management and treatment. We use the PRISMA guidelines for 16 systematic identiﬁcation of studies on major scientiﬁc literature sources and delineate the outcomes 17 of identiﬁed studies. 18

patients in maintaining and mitigating their health problems [27][28][29]. Similarly, for tinnitus there exists 48 a plethora of smartphone apps to help patients in mitigating and managing their tinnitus symptoms 49 [30]. Although there hasn't been a cure or treatment for tinnitus, the usual course of action for treatment 50 of tinnitus involves use of tinnitus retaining, sound, or cognitive behavioral therapies [1]. Although 51 the current mode of tinnitus treatment involves face-to-face administration of the aforementioned 52 therapies, however, they can also be administered using smartphones. 53 Consequently, in recent years, there has been a notable interest in development of smartphone 54 apps aiming at helping patients for management and treatment of their tinnitus [30]. However, 55 the quality and clinical effectiveness of these smartphone apps within the context of tinnitus is 56 still questionable. Although existing literature poses many articles reviewing healthcare apps in 57 a more general context [31], a very limited literature exists with specific focus on tinnitus. While 58 Internet or smartphone based CBT has been critically reviewed [32,33], and its effectiveness has been  abstract, secondarily, full-text assessment.

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Inclusion criteria: 1) manuscripts with English language, 2) published in peer-reviewed scientific 85 journal, 3) manuscript clearly addressing the subject matters of tinnitus, CBT, or self-help.

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Exclusion criteria: 1) non-peer reviewed articles, 2) no qualitative or quantitative analysis of any 87 tinnitus smartphone app, 3) manuscripts reporting on technical details about development of the 88 app, but with missing clinical evaluation.

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From Figure 1, after removal of duplicates, n = 210 records were identified in the identification 90 phase. Next, the titles and abstracts screening of these 210 selected records for eligibility resulted in the 91 feasibility of n = 39 records for further evaluation. The full-texts of the selected 39 records were then 92 assessed for further suitability, resulting in a rejection of additional 32 records, due to several reasons: 93 5 out of the 32 records were not subjected to a peer-review process, 14 records did not perform any 94 qualitative or quantitative analysis of the respective app, or did not reference any app and 13 records 95 did not show any meaningful overlap with the content, aim and scope of this review. The review 96 selection process yielded a total of n = 7 records, whereas 1 additional article was added through a 97 manual review of references, the total number of included records was therefore n = 8.

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In an additional step, we opted to search for relevant literature in aforementioned literature  apps. Finally, a total of 37 valid tinnitus apps were identified. The names of the identified apps were 110 then used to cross-search any additional study on all previously mentioned scientific literature sources.

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The overall process did not yield any new literature study, and therefore, the total number of records 112 reviewed in this article remain n = 8.

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The list of commercially available apps for tinnitus in Google's Play Store and Apple's App Store, 115 searched through respective app market places and independent third-party mHealth app libraries 116 are given in Table 1 (Sound Therapy and Tinnitus Management) and evaluation, and reviewed in this article are marked with a dagger ( †).

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An arbitrary categorical distribution of the 36 identified commercially available smartphone apps 123 with 2 major categories and types is depicted in Figure 2. Based on the app title and description 124 in the app store, we identified 2 main categories: (1) Sound Therapy (23 apps), and (2) CBT (13 125 apps). In the 'Sound Therapy' main category, 7 apps offered tinnitus masking, while 5 apps offered 126 tinnitus habituation (habituation is the process of gradually enabling tinnitus sufferers' to find ways to 127 emotionally and psychologically cope with tinnitus sounds to find relief). Similarly, 4 apps provided 128 acoustic neuromodulation, 4 apps offered distraction from tinnitus using customized sounds, 2 apps 129 1 https://www.nhs.uk/apps-library/ Accessed: 15/01/2020  'CBT' apps for tinnitus made up the second main category, in which 7 apps provided CBT self-help, 3 131 apps were CBT chatbots, 2 apps offered CBT-Acceptance and Commitment Therapy (ACT), and 1 app 132 used Visual CBT for tinnitus relief.

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The initial screening of 210 articles and full-text assessment of 39 articles yielded a total of 8 134 articles that fulfilled the review criteria and were included in the analysis. All 8 scientific studies are 135 profiled and delineated in Table 3, along-with the characteristics of the study, and the strategy adopted 136 to validate the smartphone app. Furthermore, Table 3 reports on the final outcomes and results of 137 the study. All 8 studies reviewed in this article reported the qualitative analysis using questionnaires

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The aim of this study was to systematically identify and review scientific studies reporting on 145 smartphone apps used for the management and treatment of tinnitus. The literature identification 146 process resulted in inclusion of 8 scientific studies, for which Table 3  tinnitus retaining and sound therapy, tinnitus masking, conventional drug delivery, and even brain Tested as an alternative CBT delivery method. Test for prediction of depression severity using PHQ-9, (Generalized Anxiety Disorder) GAD-7, & Positive and Negative Affect Scale.
Depression scores of users using the app decreased significantly in comparison to book users. Both groups had lower GAD-7 scores.

Lim [51]
Woebot In terms of sound-related therapies for tinnitus management and treatment,