The COMiT'ID Study: Developing Core Outcome Domains Sets for Clinical Trials of Sound-, Psychology-, and Pharmacology-Based Interventions for Chronic Subjective Tinnitus in Adults

The Current State of Tinnitus Diagnosis and Treatment: a Multidisciplinary Expert Perspective

Tinnitus, the perception of sound without an external source, affects 15% of the population, with 2.4% experiencing significant distress. In this review, we summarize the current state of knowledge about tinnitus management with a particular focus on the translation into clinical practice. In the first section, we analyze shortcomings, knowledge gaps, and challenges in the field of tinnitus research. Then, we highlight the relevance of the diagnostic process to account for tinnitus heterogeneity and to identify all relevant aspects of the tinnitus in an individual patient, such as etiological aspects, pathophysiological mechanisms, factors that contribute most to suffering, and comorbidities. In the next section, we review available treatment options, including counselling, cognitive-behavioral therapy (CBT), hearing aids and cochlear implants for patients with a relevant hearing loss, sound generators, novel auditory stimulation approaches, tinnitus retraining therapy (TRT), pharmacological treatment, neurofeedback, brain stimulation, bimodal stimulation, Internet- and app-based digital approaches, and alternative treatment approaches. The evidence for the effectiveness of the various treatment interventions varies considerably. We also discuss differences in current respective guideline recommendations and close with a discussion of how current pathophysiological knowledge, latest scientific evidence, and patient perspectives can be translated in patient-centered care.

Psychometric evaluation of the 4C tinnitus management questionnaire for patients with tinnitus alone or tinnitus combined with hyperacusis

OBJECTIVE

To assess the psychometric properties of a new questionnaire evaluating patients' confidence in managing their tinnitus, the 4C tinnitus management questionnaire (4C), which was designed to be used in the process of cognitive behavioural therapy.

DESIGN

Retrospective cross-sectional based on patient records.

STUDY SAMPLES

99 consecutive patients who sought help for tinnitus (with or without hyperacusis) from an audiology clinic in the UK. Pure tone average (PTA) hearing thresholds, Uncomfortable Loudness Levels (ULLs), and responses to the 4C questionnaire, Tinnitus Handicap Inventory (THI), Hyperacusis Questionnaire (HQ), and Screening for Anxiety and Depression in Tinnitus (SAD-T) questionnaire were gathered from the records of patients held at the audiology department.

RESULTS

Cronbach's alpha for the 4C was 0.91, indicating high internal consistency. Exploratory factor analysis suggested a one-factor solution. Discriminant validity was supported by weak correlations between 4C scores and PTA across ears and ULLmin (the across-frequency average ULL for the ear with lower average ULL). Convergent validity was supported by moderate correlations between 4C scores and scores for the THI, HQ, and SAD-T.

CONCLUSIONS

The 4C is an internally consistent questionnaire with high convergent and discriminant validity, which can be used to assess patients' confidence in managing their tinnitus.

[Analysis of items on the short forms of the tinnitus questionnaire: Mini-TQ-12 and Mini-TQ-15]

BACKGROUND

A brief but reliable measurement of tinnitus-related distress is crucial for understanding and treatment options for this often very limiting symptom. Several self-report questionnaires are used in German-speaking countries and several short versions exist for the German translation of the Tinnitus Questionnaire (TQ).

OBJECTIVE

In the present work, the frequently used Mini-TQ-12 questionnaire and the newly developed Mini-TQ-15 questionnaire will be investigated with regard to reliability, item difficulty, sensitivity (discriminatory power), and predictive power of the items in order to facilitate a decision for one or the other questionnaire in different examination contexts.

METHODS

Data from 1409 patients with chronic tinnitus who completed the German 52-item version of the TQ and additional psychological tests (ADS‑L, BSF, PHQ, ACSA and SWOP) at the Tinnitus Centre of the Charité Universitaetsmedizin Berlin, Germany, were retrospectively analyzed. We performed external validation of items from different versions of the TQ (original version, Mini-TQ-12, and Mini-TQ-15).

RESULTS

The items of the Mini-TQ-12 and the Mini-TQ-15 predicted specifically the total score. Both short questionnaires are of comparable quality in terms of reliability and item construction (difficulty, discriminatory power).

CONCLUSION

Both questionnaires have a very good item quality and are clinically more efficient to use than the long-form TQ. If a similarity of the factor structure to the original questionnaire is required for research questions, the use of the Mini-TQ-15 is recommended.

Psychometric evaluation of the tinnitus impact questionnaire using patients seeking help for tinnitus or tinnitus with hyperacusis

OBJECTIVE

To evaluate the psychometric properties of the Tinnitus Impact Questionnaire (TIQ), whose questions focus on assessing the impact of tinnitus on the patient's day to day activities, mood, and sleep, and not on hearing difficulties.

DESIGN

This was a retrospective cross-sectional study.

STUDY SAMPLE

Data were included for 172 adult patients who attended a tinnitus and hyperacusis clinic in the UK within a six-month period and who had completed the TIQ.

RESULTS

Two items whose scores were very highly correlated with those for other items were removed, leaving seven items. Exploratory factor analysis suggested a single factor for the TIQ. A multiple causes multiple indicator model showed significant but very small direct effects of age on TIQ scores for two items, after adjustment for gender. The TIQ had excellent internal consistency, with Cronbach's alpha = 0.89. The total TIQ score was moderately to strongly correlated with scores for the Tinnitus Handicap Inventory, Screening for Anxiety and Depression-Tinnitus questionnaire, Hyperacusis Questionnaire, and Hyperacusis Impact Questionnaire, indicating convergent validity. The TIQ score was weakly correlated with the pure-tone average hearing threshold, indicating discriminant validity.

CONCLUSIONS

The TIQ is a brief, valid and internally consistent questionnaire for assessing the impact of tinnitus.

New horizons in hearing conditions

Hearing conditions such as hearing loss, tinnitus and hyperacusis are highly prevalent in the population and can severely impact communication and quality of life. Hearing is affected by multiple factors, including heredity, noise exposure, age, sex, ear disorders and lifestyle factors. Globally, hearing loss affects over 80% of adults aged 80 years and older, is often experienced in combination with other long-term health conditions and is a mid-life risk factor for dementia. To form a themed collection, we searched Age and Ageing for articles on hearing conditions published from 2000 onwards. This resulted in 22 articles included within the collection. They examined a range of important topics related to hearing healthcare and research, including noise-induced hearing loss, health service quality and safety, psychological and psychosocial consequences of hearing loss and co-morbidities of hearing loss. All articles reported on hearing loss; there were no published articles with a primary focus on other hearing conditions such as tinnitus or hyperacusis, on the health of older people from the Deaf community or on users of Cochlear implants, suggesting key gaps in knowledge and targets for future research. This New Horizons article highlights novel directions in research and practice and takes a forward look at how research into hearing conditions may develop in years to come. It highlights opportunities for the growth of patient-centred research and hearing healthcare supported by the better integration of health and care services as well as cross-speciality working to include common co-morbid health conditions.

Cognitive Behavioral Group Therapy for Chronic Tinnitus in a German Tertiary Clinical Real-World Setting

Cognitive behavioral therapy (CBT) was shown to be effective in reducing tinnitus-related distress in numerous controlled trials. Real-world data from tinnitus treatment centers are an important addition to controlled trials for demonstrating the ecological validity of the results from the randomized controlled trials. Thus, we provided the real-world data of 52 patients participating in CBT group therapies during the time period from 2010 to 2019. The groups consisted of five to eight patients with typical CBT content such as counseling, relaxation, cognitive restructuring, attention training, etc. applied through 10-12 weekly sessions. The mini tinnitus questionnaire, different tinnitus numeric rating scales and the clinical global impression were assessed in a standardized way and were analyzed retrospectively. All outcome variables showed clinically relevant changes from before to after the group therapy, which were still evident in the follow-up visit after three months. Amelioration of distress was correlated to all numeric rating scales, including tinnitus loudness but not annoyance. The observed positive effects were in a similar range as effects of controlled and uncontrolled studies. Somewhat unexpected was the observed reduction in loudness, which was associated with distress and the missing association of changes in distress with annoyance as it is generally assumed that standard CBT concepts reduce annoyance and distress, but not tinnitus loudness. Apart from confirming the therapeutic effectiveness of CBT in real-world settings, our results highlight the need for a clear definition/operationalization of outcome measures when investigating psychological interventions of tinnitus.

Establishing a Core Domain Set for early-phase clinical trials of electrical stimulation interventions for tinnitus in adults: protocol for an online Delphi study

BACKGROUND

Tinnitus is the awareness of a sound in the ear or head in the absence of an external source. It affects around 10-15% of people and current treatment options are limited. Experimental treatments include various forms of electrical stimulation of the brain. Currently, there is no consensus on the outcomes that should be measured when investigating the efficacy of this type of intervention for tinnitus. This study seeks to address this by establishing a Core Domain Set: a common standard of what specific tinnitus-related complaints are critical and important to assess in all clinical trials of electrical stimulation-based interventions for tinnitus.

METHODS

A two-round online survey will be conducted, followed by a stakeholder consensus meeting to identify a Core Domain Set. Participants will belong to one of two stakeholder groups: healthcare users with lived experience of tinnitus, and professionals with relevant clinical, commercial, or research experience.

DISCUSSION

This study will establish a Core Domain Set for the evaluation of electrical stimulation-based interventions for tinnitus via an e-Delphi study. The resulting Core Domain Set will act as a minimum standard for reporting in future clinical trials of electrical stimulation interventions for tinnitus. Standardisation will facilitate comparability of research findings.

Ginkgo biloba for tinnitus

BACKGROUND

Tinnitus is a symptom defined as the perception of sound in the absence of an external source. In England alone there are an estimated ¾ million general practice consultations every year where the primary complaint is tinnitus, equating to a major burden on healthcare services. Clinical management strategies include education and advice, relaxation therapy, tinnitus retraining therapy (TRT), cognitive behavioural therapy (CBT), sound enrichment using ear-level sound generators or hearing aids, and drug therapies to manage co-morbid symptoms such as insomnia, anxiety or depression.  OBJECTIVES: To assess the effects of Ginkgo biloba for tinnitus in adults and children.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; CENTRAL (2022, Issue 6); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 7 June 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting adults and children with acute or chronic subjective tinnitus. We included studies where the intervention involved Ginkgo biloba and this was compared to placebo, no intervention, or education and information. Concurrent use of other medication or other treatment was acceptable if used equally in each group. Where an additional intervention was used equally in both groups, we analysed this as a separate comparison. The review included all courses of Ginkgo biloba, regardless of dose regimens or formulations, and for any duration of treatment.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were tinnitus symptom severity measured as a global score on a multi-item tinnitus questionnaire and serious adverse effects (bleeding, seizures). Our secondary outcomes were tinnitus loudness (change in subjective perception), tinnitus intrusiveness, generalised depression, generalised anxiety, health-related quality of life and other adverse effects (gastrointestinal upset, headache, allergic reaction). We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

This review included 12 studies (with a total of  1915 participants). Eleven studies compared the effects of Ginkgo biloba with placebo and one study compared the effects of Ginkgo biloba with hearing aids to hearing aids alone. All included studies were parallel-group RCTs. In general, risk of bias was high or unclear due to selection bias and poor reporting of allocation concealment and blinding of participants, personnel and outcome assessments. Due to heterogeneity in the outcomes measured and measurement methods used, only limited data pooling was possible.  Ginkgo biloba versus placebo When we pooled data from two studies for the primary outcome tinnitus symptom severity, we found that Ginkgo biloba may have little to no effect (Tinnitus Handicap Inventory scores) at three to six months compared to placebo, but the evidence is very uncertain (mean difference (MD) -1.35 (scale 0 to 100), 95% confidence interval (CI) -8.26 to 5.55; 2 studies; 85 participants) (very low-certainty). Ginkgo biloba may result in little to no difference in the risk of bleeding or seizures, with no serious adverse effects reported in either group (4 studies; 1154 participants; low-certainty). For the secondary outcomes, one study found that there may be little to no difference between the effects of Ginkgo biloba and placebo on tinnitus loudness measured with audiometric loudness matching at 12 weeks, but the evidence is very uncertain (MD -4.00 (scale -10 to 140 dB), 95% CI -13.33 to 5.33; 1 study; 73 participants) (very low-certainty). One study found that there may be little to no difference between the effects of Ginkgo biloba and placebo on health-related quality of life measured with the Glasgow Health Status Inventory at three months (MD -0.58 (scale 0 to 100), 95% CI -4.67 to 3.51; 1 study; 60 participants) (low-certainty). Ginkgo biloba may not increase the frequency of other adverse effects (gastrointestinal upset, headache, allergic reaction) at three months compared to placebo (risk ratio 0.91, 95% CI 0.52 to 1.60; 4 studies; 1175 participants) (low-certainty). None of the studies reported the other secondary outcomes of tinnitus intrusiveness or changes in depressive symptoms or depression, anxiety symptoms or generalised anxiety. Gingko biloba with concurrent intervention versus concurrent intervention only One study compared Ginkgo biloba with hearing aids to hearing aids only. It assessed the mean difference in the change in Tinnitus Handicap Inventory scores and tinnitus loudness using a 10-point visual analogue scale (VAS) at three months. The study did not report adverse effects, tinnitus intrusiveness, changes in depressive symptoms or depression, anxiety symptoms or generalised anxiety, or health-related quality of life. This was a single, very small study (22 participants) and for all outcomes the certainty of the evidence was very low. We were unable to draw meaningful conclusions from the numerical results.

AUTHORS' CONCLUSIONS

There is uncertainty about the benefits and harms of Ginkgo biloba for the treatment of tinnitus when compared to placebo. We were unable to draw meaningful conclusions regarding the benefits and harms of Ginkgo biloba when used with concurrent intervention (hearing aids). The certainty of the evidence for the reported outcomes, assessed using GRADE, ranged from low to very low. Future research into the effectiveness of Ginkgo biloba in patients with tinnitus should use rigorous methodology. Randomisation and blinding should be of the highest quality, given the subjective nature of tinnitus and the strong likelihood of a placebo response. The CONSORT statement should be used in the design and reporting of future studies. We also recommend the use of validated, patient-centred outcome measures for research in the field of tinnitus.

Effectiveness and cost effectiveness of digital hearing aids in patients with tinnitus and hearing loss: a randomised feasibility trial (THE HUSH Trial)

Background

Education and advice is provided for tinnitus management in all UK audiology clinics. Sound therapy, including provision of hearing aids may be offered, but this is often dependent on a clinician’s decision rather than UK policy. This inconsistent management reflects a lack of evidence around the effectiveness of hearing aids for tinnitus. This open-label, two-arm multicentre randomised controlled feasibility trial gathered data around recruitment, acceptability and outcome assessments to determine the feasibility of conducting a large randomised controlled trial investigating the effectiveness of hearing aids for tinnitus management.

Methods

Adults referred to audiology for tinnitus, with an aidable hearing loss were recruited at five UK audiology clinics. They were randomised 1:1 to either education and advice (treatment as usual (TAU), n = 41) or TAU plus hearing aids (n = 42). Outcomes were collected by questionnaires 12 weeks after randomisation. After participation, interviews were conducted with a subset of both participants and clinicians from each trial centre.

Results

Eighty three participants from five sites were randomised. Non-aidable hearing loss was the main reason for ineligibility to participate in the trial reported by the sites. Seventy three percent of participants returned the 12-week questionnaires, with return rates by site ranging from 61 to 100%. Fifteen out of 33 participants (45%) reported using hearing aids for the clinician-recommended time, or longer, during the day. The Tinnitus Functional Index (TFI) was the outcome measure most responsive to change. The majority of participants also agreed it was relevant to their tinnitus and hearing loss. Qualitative data demonstrated that the trial was acceptable to participants. Feedback from clinicians revealed a potential lack of equipoise. It also highlighted the differences in referral and treatment pathways between departments and differences in audiometric criteria for fitting hearing aids. Health economic measures were well completed for those returned. No change in health-related quality of life was observed. Costs were higher in the intervention arm, but self-reports of healthcare service use indicated participant confusion in treatment pathways.

Conclusions

This feasibility trial is the first step towards obtaining high quality evidence to determine potential clinical effectiveness and cost effectiveness of hearing aids for tinnitus versus usual care. A definitive trial was deemed to be feasible, with some modifications based on feasibility findings and using the TFI as the primary outcome.

This trial was funded by the National Institute for Health Research, Research for Patient Benefit Programme (PB-PG-0816–20,014) and registered with ISRCTN (ISRCTN14218416).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-022-01188-9.

ICF domains covered by the Tinnitus Questionnaire and Tinnitus Functional Index

PURPOSE

Tinnitus frequently causes disability as it affects daily living, which is objectified using several tinnitus questionnaires. To what extent they cover domains of the International Classification of Functioning, Disability and Health (ICF) is currently unknown. Therefore, this study aims to investigate which ICF domains are measured by two questionnaires and to describe the health status of somatic tinnitus patients in ICF terms.

MATERIALS AND METHODS

All questions of the Tinnitus Questionnaire (TQ) and Tinnitus Functional Index (TFI) were linked to the ICF using linking rules. A count-based method was used to link all individual answers of 80 tinnitus patients, to the ICF categories.

RESULTS

Most of the linked questions concerned "body functions". TFI covered more categories of "activity and participation" than TQ. Patients reported severe impairments in "mental functions", "sensory functions and pain", and "sleep functions". Additionally, severe limitations were scored in "focusing attention".

CONCLUSIONS

The TFI and TQ measure distinct domains but can be used complementary or solely, depending on the research question. The TFI identifies a broad spectrum of problems, where the TQ focuses on the psychological impact of tinnitus. Somatic patients in our study reported impairments and disabilities in all covered domains, especially in "onset of sleep" and "sound detection".Implications for RehabilitationThe Tinnitus Functional Index (TFI) and the Tinnitus Questionnaire (TQ) cover different domains of the International Classification of Functioning, Disability and Health.The TFI identifies problems in "body functions" and "activity and participation".The TQ focuses on the psychological impact of tinnitus.

The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) study: International consensus on outcome measures for trials of interventions for adults with single-sided deafness

Background

Single-sided deafness (SSD) has functional, psychological, and social consequences. Interventions for adults with SSD include hearing aids and auditory implants. Benefits and harms (outcome domains) of these interventions are until now reported inconsistently in clinical trials. Inconsistency in reporting outcome measures prevents meaningful comparisons or syntheses of trial results. The Core Rehabilitation Outcome Set for Single-Sided Deafness (CROSSSD) international initiative used structured communication techniques to achieve consensus among healthcare users and professionals working in the field of SSD. The novel contribution is a set of core outcome domains that experts agree are critically important to assess in all clinical trials of SSD interventions.

Methods

A long list of candidate outcome domains compiled from a systematic review and published qualitative data, informed the content of a two-round online Delphi survey. Overall, 308 participants from 29 countries were enrolled. Of those, 233 participants completed both rounds of the survey and scored each outcome domain on a 9-point scale. The set of core outcome domains was finalised via a web-based consensus meeting with 12 participants. Votes involved all stakeholder groups, with an approximate 2:1 ratio of professionals to healthcare users participating in the Delphi survey, and a 1:1 ratio participating in the consensus meeting.

Results

The first round of the survey listed 44 potential outcome domains, organised thematically. A further five outcome domains were included in Round 2 based on participant feedback. The structured voting at round 2 identified 17 candidate outcome domains which were voted on at the consensus meeting. Consensus was reached for a core outcome domain set including three outcome domains: spatial orientation, group conversations in noisy social situations, and impact on social situations. Seventy-seven percent of the remaining Delphi participants agreed with this core outcome domain set.

Conclusions

Adoption of the internationally agreed core outcome domain set would promote consistent assessment and reporting of outcomes that are meaningful and important to all relevant stakeholders. This consistency will in turn enable comparison of outcomes reported across clinical trials comparing SSD interventions in adults and reduce research waste. Further research will determine how those outcome domains should best be measured.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06702-1.

A randomized single-blind controlled trial of a prototype digital polytherapeutic for tinnitus

Objective

This randomized single-blind controlled trial tested the hypothesis that a prototype digital therapeutic developed to provide goal-based counseling with personalized passive and active game-based sound therapy would provide superior tinnitus outcomes, and similar usability, to a popular passive sound therapy app over a 12 week trial period.

Methods

The digital therapeutic consisted of an app for iPhone or Android smartphone, Bluetooth bone conduction headphones, neck pillow speaker, and a cloud-based clinician dashboard to enable messaging and app personalization. The control app was a popular self-help passive sound therapy app called White Noise Lite (WN). The primary outcome measure was clinically meaningful change in Tinnitus Functional Index (TFI) between baseline and 12 weeks of therapy. Secondary tinnitus measures were the TFI total score and subscales across sessions, rating scales and the Client Oriented Scale of Improvement in Tinnitus (COSIT). Usability of the US and WN interventions were assessed using the System Usability Scale (SUS) and the mHealth App Usability Questionnaire (MAUQ). Ninety-eight participants who were smartphone app users and had chronic moderate-severe tinnitus (>6 months, TFI score > 40) were enrolled and were randomly allocated to one of the intervention groups. Thirty-one participants in the USL group and 30 in the WN group completed 12 weeks of trial.

Results

Mean changes in TFI for the USL group at 6 (16.36, SD 17.96) and 12 weeks (17.83 points, SD 19.87) were clinically meaningful (>13 points reduction), the mean change in WN scores were not clinically meaningful (6 weeks 10.77, SD 18.53; 12 weeks 10.12 points, SD 21.36). A statistically higher proportion of USL participants achieved meaningful TFI change at 6 weeks (55%) and 12 weeks (65%) than the WN group at 6 weeks (33%) and 12 weeks (43%). Mean TFI, rating and COSIT scores favored the US group but were not statistically different from WN. Usability measures were similar for both groups.

Conclusions

The USL group demonstrated a higher proportion of responders than the WN group. The usability of the USL therapeutic was similar to the established WN app. The digital polytherapeutic demonstrated significant benefit for tinnitus reduction supporting further development.

Daily Contributors of Tinnitus Loudness and Distress: An Ecological Momentary Assessment Study

Background

Tinnitus is a heterogeneous condition which may be associated with moderate to severe disability, but the reasons why only a subset of individuals is burdened by the condition are not fully clear. Ecological momentary assessment (EMA) allows a better understanding of tinnitus by capturing the fluctuations of tinnitus symptoms, such as distress and loudness, and psychological processes, such as emotional arousal, overall stress, mood, and concentration and how these variables interact over time. Whether any of those variables have an influence over the next day, that is, whether any of these variables are auto- or cross-correlated, is still unanswered.

Objectives

Assess whether behavioral and symptom-related data from tinnitus users from the TrackYourTinnitus (TYT) mobile app have an impact on tinnitus loudness and distress on subsequent days.

Methods

Anonymized data was collected from 278 users of the iOS or Android TYT apps between 2014 and 2020. Tinnitus-related distress, tinnitus loudness, concentration level, mood, emotional arousal, and overall stress level were assessed using either a slider or the Wong-Baker Pain FACES scale via a daily survey. Three modeling strategies were used to investigate whether tinnitus loudness and distress are affected by previous days symptoms or psychological processes: auto- and cross correlations, regressions with elastic net regularization, and subgrouping within group iterative multiple model estimation (S-GIMME).

Results

No autocorrelation or cross-correlation was observed at the group level between the variables assessed. However, application of the regression models with elastic net regularization identified individualized predictors of tinnitus loudness and distress for most participants, with the models including contemporaneous and lagged information from the previous day. S-GIMME corroborated these findings by identifying individualized predictors of tinnitus loudness and distress from the previous day.

Discussion

We showed that tinnitus loudness and tinnitus distress are affected by the contemporaneous and lagged dynamics of behavioral and emotional processes measured through EMA. These effects were seen at the group, and individual levels. The relevance EMA and the implications of the insights derived from it for tinnitus care are discussed, especially considering current trends toward the individualization of tinnitus care.

Effect of electrical stimulation with a cochlear implant on tinnitus impact: protocol of an individual patient data meta-analysis

INTRODUCTION

Tinnitus is the perception of sound without an external stimulus, often experienced as a ringing, buzzing sound. While several studies have shown a reduction in tinnitus distress following cochlear implantation, others showed an increase or no change after implantation. At this stage, clinicians have little certainty when counselling their patients prior to implantation regarding tinnitus post-implantation. To help clinicians to counsel cochlear implant (CI) candidates on the risk of developing or improving tinnitus after implantation, we aim to assess the effect of electrical stimulation with a CI on tinnitus impact for individual adult patients with tinnitus. We will also apply prediction models to individual patient data (IPD) of clinical trials to find predictive factors of the effect of electrical stimulation on tinnitus impact.

METHOD AND ANALYSIS

The IPD meta-analysis is a follow-up project of the systematic review on cochlear implantation in patients with tinnitus as a primary complaint. First, the systematic searches will be updated to date. Methodological quality of eligible studies will be assessed using the Risk of Bias In Non-randomised Studies of Intervention tool (ROBINS-I). Based on a data-sharing agreement, authors of the eligible studies will be invited to share their deidentified and complete IPD. The primary outcome is the effect of electrical stimulation with a CI on tinnitus impact 1 month or more post-implantation. IPD meta-analysis will be used to assess the primary outcome, while differentiating the tinnitus impact questionnaires. Second, linear regression analyses will be used to model the effect of electrical stimulation on tinnitus impact based on relevant predictors.

ETHICS AND DISSEMINATION

The Medical Research Involving Human Subject Act does not apply, and ethical approval is not required. The study results will be made accessible to the public in a peer-review open access journal.

PROSPERO REGISTRATION NUMBER

CRD42022319367, review ongoing.

Reevaluating the Use of Sound Therapy for Tinnitus Management: Perspectives on Relevant Systematic Reviews

PURPOSE

Tinnitus is a highly prevalent condition that can severely reduce health functioning. In spite of extant clinical practice guidelines (CPGs), implementation of these CPGs is relatively uncommon. As a result, patients seeking professional services for tinnitus often have no assurance of receiving evidence-based care. The purpose of this tutorial was to clarify the evidence for sound therapy so that it may be included in future CPGs for tinnitus.

METHOD

"Best clinical evidence" is obtained from high-quality systematic reviews, which are generally considered the highest level of evidence. Our review of recent, comprehensive, high-quality systematic reviews of interventions for tinnitus concludes that cognitive behavioral therapy is the only effective intervention, though the strength of evidence was generally rated as low in these reviews. Although trials of sound therapy for tinnitus have been included in these reviews, they have been rated as having high risk of bias (RoB) and not included in syntheses or rated as insufficient strength of evidence.

RESULTS

Conclusions from these and other reviews have influenced recommendations made in CPGs for tinnitus. These conclusions, however, can make it appear that an intervention for tinnitus is not effective, even if the opposite is true. We contend that the strict inclusion criteria for these reviews are counterproductive and have the effect of obscuring decades of evidence demonstrating the clinical effectiveness of sound therapies for tinnitus. Ultimately, this process has resulted in many patients not receiving sound therapy, despite what should be sufficient evidence that this is an effective form of intervention.

CONCLUSION

If we rely on systematic reviews using contemporary RoB assessment criteria for studies published prior to these reporting guidelines, then we risk excluding important conclusions regarding interventions that could help patients in need.

Prevention of Noise-Induced Hearing Loss Using Investigational Medicines for the Inner Ear: Previous Trial Outcomes Should Inform Future Trial Design

Significance: Noise-induced hearing loss (NIHL) is an important public health issue resulting in decreased quality of life for affected individuals, and significant costs to employers and governmental agencies. Recent Advances: Advances in the mechanistic understanding of NIHL have prompted a growing number of proposed, in-progress, and completed clinical trials for possible protections against NIHL via antioxidants and other drug agents. Thirty-one clinical trials evaluating prevention of either temporary or permanent NIHL were identified and are reviewed. Critical Issues: This review revealed little consistency in the noise-exposed populations in which drugs are evaluated or the primary outcomes used to measure NIHL prevention. Changes in pure-tone thresholds were the most common primary outcomes; specific threshold metrics included both average hearing loss and incidence of significant hearing loss. Changes in otoacoustic emission (OAE) amplitude were relatively common secondary outcomes. Extended high-frequency (EHF) hearing and speech-in-noise perception are commonly adversely affected by noise exposure but are not consistently included in clinical trials assessing prevention of NIHL. Future Directions: Multiple criteria are available for monitoring NIHL, but the specific criterion to be used to define clinically significant otoprotection remains a topic of discussion. Audiogram-based primary outcome measures can be combined with secondary outcomes, including OAE amplitude, EHF hearing, speech-in-noise testing, tinnitus surveys, and patient-reported outcomes. Standardization of test protocols for the above primary and secondary outcomes, and associated reporting criterion for each, would facilitate clinical trial design and comparison of results across investigational drug agents. Antioxid. Redox Signal. 36, 1171-1202.

Defining a Patient-Centred Core Outcome Domain Set for the Assessment of Hearing Rehabilitation With Clients and Professionals

Background

A variety of outcome domains are currently measured for the assessment of hearing rehabilitation. To date, there is no consensus about which outcome domains should be measured, when they should be measured, and how they should be measured. In addition, most studies seeking to develop core outcome sets and measures for hearing rehabilitation services have primarily focussed on the opinions and expertise of researchers, and, to a lesser extent, clinicians, rather than also involving clients of those services. The principles of experience-based co-design suggest that health services, researchers, and policymakers should come together with clients and their families to design health services and define what metrics should be used for their success.

Objectives

This study aimed to seek views and consensus from a range of key stakeholders to define which client-centred self-report outcome domains should be measured, when they should be measured, and how they should be measured, in a national publicly funded hearing rehabilitation scheme. In addition, the study aimed to identify current and future potential mechanisms and systems to standardise the collection of data and reporting of outcomes, to enable comparison across clients and hearing service providers.

Methods

Two stakeholder groups participated in a three-round online Delphi process: (1) 79 professional stakeholders involved in the delivery of hearing services in Australia, and (2) 64 hearing rehabilitation services’ clients identified by not-for-profit consumer organisations. An initial set of in-person workshops scoped the key issues upon which to develop the initial open-ended questions and subsequent Likert-scale statements addressing these issues. These statements were then distributed to both groups in an online survey. The respondent ratings were summarised, and the summary was returned to respondents along with a second round of the survey. This process was then repeated once more. The five most important outcome domains from both groups were then combined, and a consensus workshop of seven professionals and three client advocates agreed on the top four ranked domains.

Results

A range of potential outcome domains were identified as relevant indicators of successful hearing rehabilitation. Communication ability, personal relationships, wellbeing, and participation restrictions were identified as a core outcome domain set that should be measured as a minimum for patients receiving hearing rehabilitation. There was little agreement on the preferred timepoints for collection of outcome measures, with respondents expressing the view that this should be established by research once a set of outcome measures has been selected. However, there was broad agreement that measurements of these domains should be collected at baseline (before the provision of hearing rehabilitation) and no earlier than 3 months following the completion of rehabilitation. Potential benefits and issues with the development of a national outcomes database/collection system were also identified and prioritised, with participants highlighting the importance of valid, high-quality, trustworthy, and comprehensive data collection.

Conclusion

These results provide a Core Outcome Domain Set for the self-reported evaluation of hearing rehabilitation and provide important background information for the design of methods to implement them across hearing healthcare systems. However, the wide range of outcome domains identified as potentially providing important additional information and the lack of specific measures to address these domains strongly suggest that there is still more research to be done. Ongoing stakeholder engagement will continue to be vital for future implementation. In addition, further research is required to determine the optimal time following hearing rehabilitation to utilise any particular outcome measure.

Systematic Evaluation of the T30 Neurostimulator Treatment for Tinnitus: A Double-Blind Randomised Placebo-Controlled Trial with Open-Label Extension

Tinnitus is often triggered by cochlear damage and has been linked with aberrant patterns of neuronal activity. Acoustic Coordinated Reset (CR^®) Neuromodulation is a sound therapy hypothesised to reduce tinnitus symptoms by desynchronising pathological brain activity using a portable acoustic device (the T30 neurostimulator). We report results of a pivotal trial to test the efficacy of this intervention. This two-centre, double-blind randomised controlled trial with long-term open-label extension, was undertaken between February 2012 and February 2014 in the UK. Participants were 100 adults with tinnitus as a primary complaint, recruited through hearing clinics and media advertisements. Intervention was the device programmed either with the proprietary sound sequence or placebo algorithm, fit by one of five trained audiologists. Minimisation software provided group allocation (1:1 randomisation), with groups matched for age, gender, hearing loss and tinnitus severity. Allocation was masked from participants and assessors during the trial. The primary measure of efficacy was change in tinnitus symptom severity between groups, measured using the Tinnitus Handicap Questionnaire at 12 weeks. Secondary outcomes were other measures of tinnitus symptom severity, health-related quality of life, and perceptual characteristics (pitch, loudness, bandwidth) at 12 weeks, and Tinnitus Handicap Questionnaire at 36 weeks (open-label extension). A statistician blinded to the allocation conducted an intention-to-treat analysis that employed linear regressions on minimisation variables, trial centre and intervention group, with multiple imputations for missing data. The study was registered on clinicaltrials.gov (NCT01541969). We screened 391 individuals and assigned interventions to 100 eligible participants. The primary outcome was not statistically significant between groups (mean group = −0.45, 95% CI −5.25 to 4.35; p = 0.85), nor were any of the secondary outcomes. Four adverse events occurred during the trial. Analysis of tinnitus symptom severity data collected across the 24-week open-label extension showed no statistically significant within-group changes after 12, 24, or 36 weeks treatment with the proprietary sound sequence. While individual participants may benefit from sound therapy, Acoustic CR^® Neuromodulation did not lead to group-mean reductions on tinnitus symptom severity or other measures compared to placebo, or over time.

Best Practices in the Development, Translation, and Cultural Adaptation of Patient-Reported Outcome Measures for Adults With Hearing Impairment: Lessons From the Cochlear Implant Quality of Life Instruments

This manuscript summarizes available evidence-based best practices in the development, translation, and cultural adaptation of one type of outcome measure for adults with hearing impairment, patient-reported outcome measures (PROMs). It presents the development of the Cochlear Implant Quality of Life (CIQOL) instruments and the ongoing translation and cultural adaptation of the CIQOL-35 Profile from English to French as case studies and discusses useful lessons for selecting, developing, translating, culturally adapting, and using PROMs. Relevant best practice guides are introduced, described and their steps are illustrated with examples. Future trends in hearing-related PROMs, including computerized adaptive testing, patient-reported experience measures (PREMs), economic evaluation and allocation of scarce resources, and PROMs in low-resource settings, are discussed. The manuscript concludes on the lessons that can be learned from implementation science for the successful and sustainable integration of PROMs in clinical practice.

The global hearing therapeutic pipeline: 2021

Hearing loss is a serious condition affecting more than 1.5 billion people globally. Many affected people benefit from the use of devices, such as hearing aids, but these do not restore natural hearing, and many users still struggle to follow speech in the presence of background noise. Consequently, there is rapid growth in work to discover therapeutics to address this need. Our analysis of the therapeutic pipeline for inner ear and central processing disorders identified 23 assets in clinical trials and 56 in preclinical development, of which 25% have entered the pipeline in the past three years. The innovative potential of this pipeline is encouraging, but there are translational hurdles to be overcome. We highlight challenges for the pipeline and comment on opportunities to support and strengthen it.

Use of open-ended questionnaires to examine the effects of tinnitus and its relation to patient-reported outcome measures

OBJECTIVE

The primary aim of the study was to examine the automated linguistic analysis of the open-ended problem (PQ) and life-effects (LEQ) questionnaires to understand the psychological effects of tinnitus.

DESIGN

The study used a cross-sectional design. Participants completed online questionnaires which included demographic questions, several standardised patient-reported outcome measures (PROMs), and two open-ended questions focussing on PQ and LEQ related to tinnitus. The response to open-ended questions was analysed using the Linguistic Inquiry Word Count (LIWC) software to identify the frequency of text on various linguistic dimensions relevant to tinnitus.

STUDY SAMPLE

336 individuals with tinnitus.

RESULTS

The study results point to two broad findings. First, although PQ and LEQ have some similarities with PROMs (e.g. the linguistic dimension negative emotions having a weak positive correlation with anxiety and depression), no correlation with the number of dimensions suggests that the open-ended questions identify additional elements that are not captured in PROMs. Second, more linguistic dimensions from the PQ correlate with PROMs compared to LEQ suggesting that the current PROMs are problem-oriented.

CONCLUSIONS

The study results support the idea that the use of open-ended questions in addition to PROMs may help optimise the efforts in examining the effects of chronic conditions such as tinnitus.

Inclusion of participants from low-income and middle-income countries in core outcome sets development: a systematic review

OBJECTIVE

Our study aims to describe differences or similarities in the scope, participant characteristics and methods used in core outcome sets (COS) development when only participants from high-income countries (HICs) were involved compared with when participants from low-income and middle-income countries (LMICs) were also involved.

DESIGN

Systematic review.

DATA SOURCES

Annual Core Outcome Measures in Effectiveness Trials systematic reviews of COS which are updated based on SCOPUS and MEDLINE, searches. The latest systematic review included studies published up to the end of 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included studies reporting development of a COS for use in research regardless of age, health condition or setting. Studies reporting the development of a COS for patient-reported outcomes or adverse events or complications were also included.

DATA EXTRACTION AND SYNTHESIS

Data were extracted in relation to scope of the COS study, participant categories and the methods used in outcome selection.

RESULTS

Studies describing 370 COS were identified in the database. Of these, 75 (20%) included participants from LMICs. Only four COS were initiated from an LMIC setting. More than half of COS with LMIC participants were developed in the last 5 years. Cancer and rheumatology were the dominant disease domains. Overall, over 259 (70%) of COS explicitly reported including clinical experts; this was higher where LMIC participants were also included 340 (92%). Most LMIC participants were from China, Brazil and South Africa. Mixed methods for consensus building were used across the two settings.

CONCLUSION

Progress has been made in including LMIC participants in the development of COS, however, there is a need to explore how to enable initiation of COS development from a range of LMIC settings, how to ensure prioritisation of COS that better reflects the burden of disease in these contexts and how to improve public participation from LMICs.

Patient participation in Delphi surveys to develop core outcome sets: systematic review

OBJECTIVES

To describe the design and conduct of core outcome set (COS) studies that have included patients as participants, exploring how study characteristics might impact their response rates.

DESIGN

Systematic review of COS studies published between 2015 and 2019 that included more than one patient, carer or representative as participants (hereafter referred to as patients for brevity) in scoring outcomes in a Delphi.

RESULTS

There were variations in the design and conduct of COS studies that included patients in the Delphi process, including differing: scoring and feedback systems, approaches to recruiting patients, length of time between rounds, use of reminders, incentives, patient and public involvement, and piloting. Minimal reporting of participant characteristics and a lack of translation of Delphi surveys into local languages were found. Additionally, there were indications that studies that recruited patients through treatment centres had higher round two response rates than studies recruiting through patient organisations.

CONCLUSIONS

Variability was striking in how COS Delphi surveys were designed and conducted to include patient participants and other stakeholders. Future research is needed to explore what motivates patients to take part in COS studies and what factors influence COS developer recruitment strategies. Improved reporting would increase knowledge of how methods affect patient participation in COS Delphi studies.

Surrounded by Sound: The Impact of Tinnitus on Musicians

AIM

To investigate the impact of tinnitus on professional musicians in the UK.

BACKGROUND

Tinnitus is the experience of sound when an external source is absent, primarily associated with the ageing process, hearing loss, and noise exposure. Amongst populations exposed to industrial noise, noise exposure and noise-induced hearing loss (NIHL) have been found to be the factors most associated with tinnitus. The risk of NIHL amongst professional musicians is greater than that amongst the general population, meaning they may be at increased risk of tinnitus.

METHODS

Seventy-four professional musicians completed an online survey involving closed and open-ended questions, and completed the Tinnitus fuctional Index (TFI) questionnaire. Descriptive statistics and thematic analysis of open-ended qualitative responses were used to analyse the data.

RESULTS

Three themes were generated from the analysis of the responses to the open-ended questions. These themes were: (1) the impact of tinnitus on the lives of professional musicians, (2) professional musician experience of tinnitus services, support, and hearing health and safety, and (3) the support professional musicians want. The mean global TFI score for professional musicians was 39.05, interpreted as tinnitus being a moderate problem. Comparisons with general population data revealed lower TFI scores for the TFI subscales of 'sense of control' and 'intrusiveness' for professional musicians and higher for auditory difficulties associated with tinnitus amongst professional musicians.

CONCLUSION

Tinnitus can negatively impact on professional musicians' lives. There is a need for bespoke self-help groups, awareness raising, and education to prevent tinnitus and promote hearing health among musicians.

Validation of a Dutch version of the Tinnitus Functional Index in a tertiary referral tinnitus clinic

INTRODUCTION

Tinnitus is a condition with a subjective nature that requires self-report questionnaires for its assessment. Aspects such as quality of life, sleep or intrusiveness have been addressed by multiple tinnitus questionnaires, but the high responsiveness to treatment effects of the Tinnitus Functional Index (TFI) makes this questionnaire part of the standard practice in tinnitus screening. To date, the TFI has been translated to more than 20 languages and used in more than 22 countries. In this study, the TFI was translated to Dutch and validated through a clinical population in the Netherlands.

METHODS

After a back-translation procedure, the Dutch TFI was filled-out by 377 patients in the tinnitus outpatient clinic at the Ear, Nose and Throat (ENT) department of the University Medical Center Groningen, in the Netherlands. Reliability and construct validity of the questionnaire were assessed by correlations with one other tinnitus questionnaire (Tinnitus Handicap Inventory, THI) and with three psychological functioning questionnaires (Rand-36, Cantril's ladder and the Hospital Anxiety and Depression Scale (HADS)). The eight-factor structure of the Dutch TFI was tested by means of exploratory factor analysis using three different models (ICM-CFA, ESEM and ESEM-CFA).

RESULTS

The Dutch TFI showed a high internal consistency (α = 0.95), and construct validity was proven by moderate-to high-convergent correlations with the THI (r = 0.47-0.79) and by moderate convergent (r = 0.55-0.67) and good-to moderate-divergent (r = 0.12-0.47) correlations with the psychological functioning questionnaires. The eight-factor structure of the TFI was confirmed for the Dutch version by the three models.

CONCLUSION

The Dutch version of the TFI is a reliable instrument for screening tinnitus impact in a clinical population, and its psychometric properties are comparable to the original TFI and other validated tinnitus questionnaires.

Hearing Aid Fitting in Tinnitus: A Scoping Review of Methodological Aspects and Effect on Tinnitus Distress and Perception

Current evidence on efficacy of hearing aids (HAs) on tinnitus perception and annoyance is considered insufficient due to the heterogeneity of tinnitus characteristics and of methods used in the relevant clinical studies. This is a scoping review focused on the methodological aspects of clinical studies evaluating the value of HA fitting as part of tinnitus management over the past 10 years. Thirty-four studies were included in the review, showing important heterogeneity in almost all aspects of inclusion criteria, comparators, outcome measures, follow-up time and HA fitting procedures. Although all studies show that HA fitting has a positive impact on tinnitus perception in patients with hearing loss, the methodological heterogeneity does not allow robust conclusions. Future studies taking into account the different nature and goals of each tinnitus therapeutic modality and adapting their methods, endpoints and timelines according to them could lay the groundwork for obtaining high-quality evidence on whether and how HA fitting shall be implemented in tinnitus management strategies.

Intervention Planning for the Tinnitus E-Programme 2.0, an Internet-Based Cognitive Behavioral Intervention for Tinnitus

Purpose The purpose of this study is to comprehensively describe the intervention planning process for the Tinnitus E-Programme 2.0, an Internet-based cognitive behavioral intervention for tinnitus. Method Theory-, evidence-, and person-based approaches to intervention development were used. In Phase 1, quantitative systematic reviews were used to identify potentially effective intervention techniques and design features. Primary mixed-methods research involving adults with tinnitus explored the acceptability of the first version of the intervention. In Phase 2, person-based guiding principles highlighted key intervention design objectives and features to address needs of the intervention's target group (identified in Phase 1) to maximize its acceptability, feasibility of delivery, and effectiveness. Theory-based "behavioral analysis" and "logic modeling" comprehensively described intervention content and potential mechanisms of action. From this planning work, a prototype intervention was developed. Results The intervention design objectives outlined in the guiding principles were to (a) normalize tinnitus, (b) support users to maintain a regular relaxation practice, (c) minimize the worsening of users' tinnitus sensation, and (d) ensure the intervention is accessible to those with hearing loss. Behavioral analysis and logic modeling identified intervention processes (e.g., illness perceptions, beliefs about consequences, skills, goals) and purported mediators (acceptance of tinnitus, negative thinking, use of the cognitive skills tools for managing negative thoughts, and practicing regular relaxation) hypothesized to facilitate reductions in tinnitus symptom severity. Conclusions The guiding principles highlight key design objectives and features to consider when developing interventions for tinnitus. The logic model offers hypothesized mechanisms of action that can be tested in future process analyses.

Multidisciplinary Tinnitus Research: Challenges and Future Directions From the Perspective of Early Stage Researchers

Tinnitus can be a burdensome condition on both individual and societal levels. Many aspects of this condition remain elusive, including its underlying mechanisms, ultimately hindering the development of a cure. Interdisciplinary approaches are required to overcome long-established research challenges. This review summarizes current knowledge in various tinnitus-relevant research fields including tinnitus generating mechanisms, heterogeneity, epidemiology, assessment, and treatment development, in an effort to highlight the main challenges and provide suggestions for future research to overcome them. Four common themes across different areas were identified as future research direction: (1) Further establishment of multicenter and multidisciplinary collaborations; (2) Systematic reviews and syntheses of existing knowledge; (3) Standardization of research methods including tinnitus assessment, data acquisition, and data analysis protocols; (4) The design of studies with large sample sizes and the creation of large tinnitus-specific databases that would allow in-depth exploration of tinnitus heterogeneity.

What Tinnitus Therapy Outcome Measures Are Important for Patients?- A Discrete Choice Experiment

Introduction: The therapeutic rationale varies among tinnitus therapies. A recent study identified which outcome measures should be used for different types of interventions. What patients consider the most important outcome measure in tinnitus therapy is unclear.

Objectives: To study the preference of the tinnitus patient for different outcome measures in tinnitus therapy.

Methods: A discrete choice experiment was conducted. Participants were provided with two alternatives per choice set (nine choice sets total). Each choice-set consisted of four attributes (tinnitus loudness, tinnitus acceptance, quality of sleep and concentration). With a difference in one of three levels (increased, similar or decreased after treatment) between the alternatives. Results were analyzed with a mixed logit model. Preference heterogeneity was explored with covariates, correlating attributes and a latent class analysis.

Results: One hundred and twenty-seven participants took part. In the mixed logit models we found that the choice for a tinnitus therapy was significantly affected by all levels of the outcomes, except for a similar level in concentration and tinnitus acceptance. Tinnitus loudness was considered the most important outcome measure relative to the other attributes. Preference heterogeneity was not explained by correlating attributes. The latent class analysis identified two classes. The first class was similar to the mixed logit analysis, except for a non-significance of similar quality of sleep and tinnitus acceptance. The second class showed a statistical significant preference only for increased tinnitus acceptance and similar quality of sleep.

Conclusion: Based on this study, tinnitus patients consider loudness the most important outcome measure. However, there is a variance in preference as indicated by the latent class analysis. This study underlines the importance of research into tinnitus heterogeneity. Next, this study highlights the need for research into tinnitus therapies that focus on diminishing tinnitus loudness.

All for One and One for All? - Examining Convergent Validity and Responsiveness of the German Versions of the Tinnitus Questionnaire (TQ), Tinnitus Handicap Inventory (THI), and Tinnitus Functional Index (TFI)

BACKGROUND

Measurement of tinnitus-related distress and treatment responsiveness is key in understanding, conceptualizing and addressing this often-disabling symptom. Whilst several self-report measures exist, the heterogeneity of patient populations, available translations, and treatment contexts requires ongoing psychometric replication and validation efforts.

OBJECTIVE

To investigate the convergent validity and responsiveness of the German versions of the Tinnitus Questionnaire [TQ], Tinnitus Handicap Inventory [THI], and Tinnitus Functional Index [TFI] in a large German-speaking sample of patients with chronic tinnitus who completed a psychologically anchored 7-day Intensive Multimodal Treatment Programme.

METHODS

Two-hundred-and-ten patients with chronic tinnitus completed all three questionnaires at baseline and post-treatment. Intraclass correlation coefficients determined the convergent validity of each questionnaire's total and subscale scores. Treatment responsiveness was investigated by [a] comparing treatment-related change in responders vs. non-responders as classified by each questionnaire's minimal clinically important difference-threshold, and [b] comparing agreement between the questionnaires' responder classifications.

RESULTS

The total scores of all three questionnaires showed high agreement before and after therapy (TQ | THI: 0.80 [Pre], 0.83 [Post], TQ | TFI: 0.72 [Pre], 0.78 [Post], THI | TFI: 0.76 [Pre] 0.80 [Post]). All total scores changed significantly with treatment yielding small effect sizes. The TQ and TFI yielded comparable (19.65 and 18.64%) and the THI higher responder rates (38.15%). The TQ | THI and TQ | TFI showed fair, and the THI | TFI moderate agreement of responder classifications. Independent of classification, responders showed significantly higher change rates than non-responders across most scores. Each questionnaire's total change score distinguished between responders and non-responders as classified by the remaining two questionnaires.

CONCLUSION

The total scores of all three questionnaires show high convergent validity and thus, comparability across clinical and research contexts. By contrast, subscale scores show high inconsistency. Whilst the TFI appears well suited for research purposes, the THI may be better suited to measure psychological aspects of tinnitus-related distress and their changes with accordingly focused treatment approaches.

Emerging Topics in the Behavioral Neuroscience of Tinnitus

This volume has highlighted the many recent advances in tinnitus theory, models, diagnostics, therapies, and therapeutics. But tinnitus knowledge is far from complete. In this chapter, contributors to the Behavioral Neuroscience of Tinnitus consider emerging topics and areas of research needed in light of recent findings. New research avenues and methods to explore are discussed. Issues pertaining to current assessment, treatment, and research methods are outlined, along with recommendations on new avenues to explore with research.

Systematic review of international Delphi surveys for core outcome set development: representation of international patients

OBJECTIVES

A core outcome set (COS) describes a minimum set of outcomes to be reported by all clinical trials of one healthcare condition. Delphi surveys are frequently used to achieve consensus on core outcomes. International input is important to achieve global COS uptake. We aimed to investigate participant representation in international Delphi surveys, with reference to the inclusion of patients and participants from low and middle income countries as stakeholders (LMICs).

DESIGN

Systematic review.

DATA SOURCES

EMBASE, Medline, Web of Science, COMET database and hand-searching.

ELIGIBILITY CRITERIA

Protocols and studies describing Delphi surveys used to develop an international COS for trial reporting, published between 1 January 2017 and 6 June 2019.

DATA EXTRACTION AND SYNTHESIS

Delphi participants were grouped as patients or healthcare professionals (HCPs). Participants were considered international if their country of origin was different to that of the first or senior author. Data extraction included participant numbers, country of origin, country income group and whether Delphi surveys were translated. We analysed the impact these factors had on outcome prioritisation.

RESULTS

Of 90 included studies, 69% (n=62) were completed and 31% (n=28) were protocols. Studies recruited more HCPs than patients (median 60 (IQR 30-113) vs 30 (IQR 14-66) participants, respectively). A higher percentage of HCPs was international compared with patients (57% (IQR 37-78) vs 20% (IQR 0-68)). Only 31% (n=28) studies recruited participants from LMICs. Regarding recruitment from LMICs, patients were under-represented (16% studies; n=8) compared with HCPs (22%; n=28). Few (7%; n=6) studies translated Delphi surveys. Only 3% studies (n=3) analysed Delphi responses by geographical location; all found differences in outcome prioritisation.

CONCLUSIONS

There is a disproportionately lower inclusion of international patients, compared with HCPs, in COS-development Delphi surveys, particularly within LMICs. Future international Delphi surveys should consider exploring for geographical and income-based differences in outcome prioritisation.

PROSPERO REGISTRATION NUMBER

CRD42019138519.

Tinnitus and stress in adults: a scoping review

OBJECTIVE

Tinnitus and stress are recurrently reported together. The strength and direction of this relationship is not clear. The aim of this review is to catalogue the evidence of this relationship, how it has been described in adults and which instruments were used.

DESIGN

Five-stage framework was followed. An online search of databases and published journals were conducted. The main inclusion criteria were original studies published in English and conducted in an adult human population, in which both tinnitus and stress were measured using different instruments.

STUDY SAMPLES

5699 records were identified in the searching stage and 50 studies were eligible for data extraction.

RESULTS

Measurements of perceived stress were most frequently used. Tinnitus patients tend to report louder and more bothersome tinnitus when they are stressed, but not all tinnitus patients associated stress with the onset or the severity of their tinnitus. Any positive correlation reported between stress and tinnitus levels varied in strength according to the used instrument. Post-intervention changes in stress and tinnitus levels showed inconsistency.

CONCLUSION

There is considerable room for further research to study the relationship between stress and tinnitus. We highlight principal issues that should be considered in future studies.

Protocol for a multi-centre randomised controlled stand-alone feasibility trial to assess potential effectiveness and cost-effectiveness of digital hearing aids in patients with tinnitus and hearing loss (the HUSH trial)

Background

The most common management strategy for tinnitus provided in the UK audiology clinics is education and advice. This may also be combined with some form of sound therapy (e.g. digital hearing aids). While education and advice is generally provided by all clinics, there is a marked variability in provision of hearing aids that depends very much on clinical decisions. A recent Cochrane review concluded a lack of evidence to support or refute hearing aid use as a routine intervention for people with tinnitus and hearing loss. This lack of evidence is reflected in the inconsistency of tinnitus management in the UK. The aim of the HUSH trial is to determine the feasibility of conducting a definitive randomised controlled trial (RCT) of the effectiveness and cost-effectiveness of hearing aids for adults with tinnitus and hearing loss.

Methods

This is a multicentre randomised controlled feasibility trial. Up to 100 adults, aged 18 and over, presenting to 5 UK audiology clinics with a complaint of tinnitus and measurable hearing loss are being randomised to receive either (i) education and advice (treatment as usual) or (ii) education and advice with digital hearing aids. Feasibility outcomes are being collected around recruitment, retention, patient and healthcare professional acceptability and clinical outcome assessment. Outcomes are being collected via postal questionnaire at 12 weeks post baseline. A nested interview study will supplement clinical and other outcome data, providing a detailed understanding of participants' and audiologists' experience of both tinnitus management and the research processes.

Discussion

This feasibility trial will help us to (i) determine if it is feasible to conduct a multicentre RCT comparing treatment as usual and treatment as usual plus digital hearing aids; (ii) optimise the design of a future definitive, multicentre RCT; and (iii) inform which outcome(s) is/are relevant for patients. This work presents an important first step in determining the effectiveness of hearing aids as a tinnitus management strategy.

Trial registration

ISRCTN, ISRCTN14218416. Registered on 30 July 2018.

Core Rehabilitation Outcome Set for Single Sided Deafness (CROSSSD) study: protocol for an international consensus on outcome measures for single sided deafness interventions using a modified Delphi survey

BACKGROUND

Single-sided deafness (SSD) describes the presence of a unilateral severe to profound sensorineural hearing loss. SSD disrupts spatial hearing and understanding speech in background noise. It has functional, psychological and social consequences. Potential options for rehabilitation include hearing aids and auditory implants. Benefits and harms of these interventions are documented inconsistently in the literature, using a variety of outcomes ranging from tests of speech perception to quality of life questionnaires. It is therefore difficult to compare interventions when rehabilitating SSD. The Core Rehabilitation Outcome Set for Single Sided Deafness (CROSSSD) study is an international initiative that aims to develop a minimum set of core outcomes for use in future trials of SSD interventions.

METHODS/DESIGN

The CROSSSD study adopts an international two-round online modified Delphi survey followed by a stakeholder consensus meeting to identify a patient-centred core outcome domain set for SSD based on what is considered critical and important for assessing whether an intervention for SSD has worked.

DISCUSSION

The resulting core outcome domain set will act as a minimum standard for reporting in future clinical trials and could have further applications in guiding the use of outcome measures in clinical practice. Standardisation will facilitate comparison of research findings.

Cognitive behavioural therapy for tinnitus

BACKGROUND

Tinnitus affects up to 21% of the adult population with an estimated 1% to 3% experiencing severe problems. Cognitive behavioural therapy (CBT) is a collection of psychological treatments based on the cognitive and behavioural traditions in psychology and often used to treat people suffering from tinnitus.

OBJECTIVES

To assess the effects and safety of CBT for tinnitus in adults.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the ENT Trials Register; CENTRAL (2019, Issue 11); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 25 November 2019.

SELECTION CRITERIA

Randomised controlled trials (RCTs) of CBT versus no intervention, audiological care, tinnitus retraining therapy or any other active treatment in adult participants with tinnitus.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Our primary outcomes were the impact of tinnitus on disease-specific quality of life and serious adverse effects. Our secondary outcomes were: depression, anxiety, general health-related quality of life, negatively biased interpretations of tinnitus and other adverse effects. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We included 28 studies (mostly from Europe) with a total of 2733 participants. All participants had had tinnitus for at least three months and their average age ranged from 43 to 70 years. The duration of the CBT ranged from 3 to 22 weeks and it was mostly conducted in hospitals or online. There were four comparisons and we were interested in outcomes at end of treatment, and 6 and 12 months follow-up. The results below only refer to outcomes at end of treatment due to an absence of evidence at the other follow-up time points. CBT versus no intervention/wait list control Fourteen studies compared CBT with no intervention/wait list control. For the primary outcome, CBT may reduce the impact of tinnitus on quality of life at treatment end (standardised mean difference (SMD) -0.56, 95% confidence interval (CI) -0.83 to -0.30; 10 studies; 537 participants; low certainty). Re-expressed as a score on the Tinnitus Handicap Inventory (THI; range 0 to 100) this is equivalent to a score 10.91 points lower in the CBT group, with an estimated minimal clinically important difference (MCID) for this scale being 7 points. Seven studies, rated as moderate certainty, either reported or informed us via personal communication about serious adverse effects. CBT probably results in little or no difference in adverse effects: six studies reported none and in one study one participant in the CBT condition worsened (risk ratio (RR) 3.00, 95% CI 0.13 to 69.87). For the secondary outcomes, CBT may result in a slight reduction in depression (SMD -0.34, 95% CI-0.60 to -0.08; 8 studies; 502 participants; low certainty). However, we are uncertain whether CBT reduces anxiety, improves health-related quality of life or reduces negatively biased interpretations of tinnitus (all very low certainty). From seven studies, no other adverse effects were reported (moderate certainty). CBT versus audiological care Three studies compared CBT with audiological care. CBT probably reduces the impact of tinnitus on quality of life when compared with audiological care as measured by the THI (range 0 to 100; mean difference (MD) -5.65, 95% CI -9.79 to -1.50; 3 studies; 444 participants) (moderate certainty; MCID = 7 points). No serious adverse effects occurred in the two included studies reporting these, thus risk ratios were not calculated (moderate certainty). The evidence suggests that CBT may slightly reduce depression but may result in little or no difference in anxiety or health-related quality of life (all low certainty) when compared with audiological care. CBT may reduce negatively biased interpretations of tinnitus when compared with audiological care (low certainty). No other adverse effects were reported for either group (moderate certainty). CBT versus tinnitus retraining therapy (TRT) One study compared CBT with TRT (including bilateral sound generators as per TRT protocol). CBT may reduce the impact of tinnitus on quality of life as measured by the THI when compared with TRT (range 0 to 100) (MD -15.79, 95% CI -27.91 to -3.67; 1 study; 42 participants; low certainty). For serious adverse effects three participants deteriorated during the study: one in the CBT (n = 22) and two in the TRT group (n = 20) (RR 0.45, 95% CI 0.04 to 4.64; low certainty). We are uncertain whether CBT reduces depression and anxiety or improves health-related quality of life (low certainty). CBT may reduce negatively biased interpretations of tinnitus. No data were available for other adverse effects. CBT versus other active control Sixteen studies compared CBT with another active control (e.g. relaxation, information, Internet-based discussion forums). CBT may reduce the impact of tinnitus on quality of life when compared with other active treatments (SMD -0.30, 95% CI -0.55 to -0.05; 12 studies; 966 participants; low certainty). Re-expressed as a THI score this is equivalent to 5.84 points lower in the CBT group than the other active control group (MCID = 7 points). One study reported that three participants deteriorated: one in the CBT and two in the information only group (RR 1.70, 95% CI 0.16 to 18.36; low certainty). CBT may reduce depression and anxiety (both low certainty). We are uncertain whether CBT improves health-related quality of life compared with other control. CBT probably reduces negatively biased interpretations of tinnitus compared with other treatments. No data were available for other adverse effects.

AUTHORS' CONCLUSIONS

CBT may be effective in reducing the negative impact that tinnitus can have on quality of life. There is, however, an absence of evidence at 6 or 12 months follow-up. There is also some evidence that adverse effects may be rare in adults with tinnitus receiving CBT, but this could be further investigated. CBT for tinnitus may have small additional benefit in reducing symptoms of depression although uncertainty remains due to concerns about the quality of the evidence. Overall, there is limited evidence for CBT for tinnitus improving anxiety, health-related quality of life or negatively biased interpretations of tinnitus.

Defining Symptom Concepts in Chronic Subjective Tinnitus: Web-Based Discussion Forum Study

Background

A minimum standard based upon consensus decision making recommends a core set of tinnitus-specific health complaints (outcome domains) that should be assessed and reported in all clinical trials as this enables comparisons to be made across studies as well as data pooling for meta-analysis.

Objective

This study aimed to further clarify how the outcome domain concepts should be defined for 5 of the core set: tinnitus intrusiveness, sense of control, acceptance of tinnitus, concentration, and ability to ignore. This step requires a clear and fully elaborated definition for each outcome domain, moving from an abstract or a vague concept to an operationalized and measurable health-related construct, so that a suitable measurement instrument can then be identified.

Methods

A series of 5 focus group–style semistructured discussions were conducted via a Web-based discussion forum, each open for 2 weeks and ending with a vote. The participants included 148 tinnitus experts who completed a preceding e-Delphi survey that had generated the original set of minimum standards. The participants were health care users living with tinnitus, health care professionals, clinical researchers, commercial representatives, and funders.

Results

The Web discussions led to a revision of all 5 original plain language definitions that had been used in the preceding e-Delphi survey. Each revised definition was voted by 8 to 53 participants and reached the prespecified threshold of 70% consensus for all except tinnitus intrusiveness. Although a single definition was not agreed upon for tinnitus intrusiveness, the majority of participants shared the view that the concept should be sufficiently broad to encapsulate a range of subdomains. The examples included tinnitus awareness, unpleasantness, and impact on different aspects of everyday life. Thematic analysis of the 5 Web-based discussion threads gave important insights into expert interpretations of each core outcome domain, generating an operationalized and measurable health construct in each case.

Conclusions

The qualitative data gathered during the Web-based discussion forum provided an important in-depth understanding of the health concepts that had raised a debate during earlier face-to-face meetings. The descriptive summaries and definitions provide sufficient operationalization of those concepts to proceed to the second stage of core outcome set development that is to identify and evaluate suitable measurement instruments. This study supports the use of Web-based peer discussion forums in defining health concepts.

Why Is There No Cure for Tinnitus?

Tinnitus is unusual for such a common symptom in that there are few treatment options and those that are available are aimed at reducing the impact rather than specifically addressing the tinnitus percept. In particular, there is no drug recommended specifically for the management of tinnitus. Whilst some of the currently available interventions are effective at improving quality of life and reducing tinnitus-associated psychological distress, most show little if any effect on the primary symptom of subjective tinnitus loudness. Studies of the delivery of tinnitus services have demonstrated considerable end-user dissatisfaction and a marked disconnect between the aims of healthcare providers and those of tinnitus patients: patients want their tinnitus loudness reduced and would prefer a pharmacological solution over other modalities. Several studies have shown that tinnitus confers a significant financial burden on healthcare systems and an even greater economic impact on society as a whole. Market research has demonstrated a strong commercial opportunity for an effective pharmacological treatment for tinnitus, but the amount of tinnitus research and financial investment is small compared to other chronic health conditions. There is no single reason for this situation, but rather a series of impediments: tinnitus prevalence is unclear with published figures varying from 5.1 to 42.7%; there is a lack of a clear tinnitus definition and there are multiple subtypes of tinnitus, potentially requiring different treatments; there is a dearth of biomarkers and objective measures for tinnitus; treatment research is associated with a very large placebo effect; the pathophysiology of tinnitus is unclear; animal models are available but research in animals frequently fails to correlate with human studies; there is no clear definition of what constitutes meaningful change or "cure"; the pharmaceutical industry cannot see a clear pathway to distribute their products as many tinnitus clinicians are non-prescribing audiologists. To try and clarify this situation, highlight important areas for research and prevent wasteful duplication of effort, the British Tinnitus Association (BTA) has developed a Map of Tinnitus. This is a repository of evidence-based tinnitus knowledge, designed to be free to access, intuitive, easy to use, adaptable and expandable.

One Size Does Not Fit All: Developing Common Standards for Outcomes in Early-Phase Clinical Trials of Sound-, Psychology-, and Pharmacology-Based Interventions for Chronic Subjective Tinnitus in Adults

Good practice in clinical trials advocates common standards for assessing and reporting condition-specific complaints ("outcome domains"). For tinnitus, there is no common standard. The Core Outcome Measures in Tinnitus International Delphi (COMiT'ID) study created recommendations that are relevant to the most common intervention approaches for chronic subjective tinnitus in adults using consensus methods. Here, the objectives were to examine why it is important to tailor outcome domain selection to the tinnitus intervention that is being evaluated in the clinical trial and to demonstrate that the COMiT'ID recommendations are robust. The COMiT'ID study used an online three-round Delphi method with three separate surveys for sound-, psychology-, and pharmacology-based interventions. Survey data were analyzed to assess quality and confidence in the consensus achieved across surveys and stakeholder groups and between survey rounds. Results found participants were highly discriminatory in their decision-making. Of the 34 outcome domains reaching the prespecified consensus definition in the final round, 17 (50%) were unique to one intervention, while only 12 (35%) were common to all three. Robustness was demonstrated by an acceptable level of agreement across and within stakeholder groups, across survey rounds, across medical specialties (for the health-care practitioners), and across health-care users with varying tinnitus duration. There were few dissenting voices, and results showed no attrition bias. In conclusion, there is compelling evidence that one set of outcomes does not fit all therapeutic aims. Our analyses evidence robust decisions by the electronic Delphi process, leading to recommendations for three unique intervention-specific outcome domain sets. This provides an important starting point for standardization.

Betahistine for tinnitus

BACKGROUND

Tinnitus is a symptom defined as the perception of sound in the absence of an external source. In England alone there are an estimated ¾ million general practice consultations every year where the primary complaint is tinnitus, equating to a major burden on healthcare services. Clinical management strategies include education and advice, relaxation therapy, tinnitus retraining therapy, cognitive behavioural therapy, sound enrichment using ear-level sound generators or hearing aids, and drug therapies to manage co-morbid symptoms such as sleep difficulties, anxiety or depression. As yet, no drug has been approved for tinnitus by a regulatory body. Nonetheless, over 100,000 prescriptions for betahistine are being filled every month in England, and nearly 10% of general practitioners prescribe betahistine for tinnitus.

OBJECTIVES

To assess the effects of betahistine in patients with subjective idiopathic tinnitus.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL, via the Cochrane Register of Studies); Ovid MEDLINE; Ovid Embase; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 23 July 2018.

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting patients of any age with acute or chronic subjective idiopathic tinnitus were included. We included studies where the intervention involved betahistine and this was compared to placebo, no intervention or education and information. We included all courses of betahistine, regardless of dose regimens or formulations and for any duration of treatment.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Our primary outcomes included tinnitus loudness and significant adverse effects (upper gastrointestinal discomfort). Our secondary outcomes included tinnitus symptom severity as measured by the global score on a multi-item tinnitus questionnaire, depressive symptoms, symptoms of generalised anxiety, health-related quality of life, other adverse effects (e.g. headache, drowsiness, allergic skin reactions (pruritis, rashes) and exacerbation of tinnitus) and tinnitus intrusiveness. We used GRADE to assess the quality of evidence for each outcome; this is indicated in italics.

MAIN RESULTS

This review included five studies (with a total of 303 to 305 participants) comparing the effects of betahistine with placebo in adults with subjective idiopathic tinnitus. Four studies were parallel-group RCTs and one had a cross-over design. The risk of bias was unclear in all of the included studies.Due to heterogeneity in the outcomes measured and measurement methods used, very limited data pooling was possible. When we pooled the data from two studies for the primary outcome tinnitus loudness, the mean difference on a 0- to 10-point visual analogue scale at one-month follow-up was not significant between betahistine and placebo (-0.16, 95% confidence interval (CI) -1.01 to 0.70; 81 participants) (very low-quality evidence). There were no reports of upper gastrointestinal discomfort (significant adverse effect) in any study.As a secondary outcome, one study found no difference in the change in the Tinnitus Severity Index between betahistine and placebo (mean difference at 12 weeks 0.02, 95% CI -1.05 to 1.09; 50 participants) (moderate-quality evidence). None of the studies reported the other secondary outcomes of changes in depressive symptoms or depression, anxiety symptoms or generalised anxiety, or health-related quality of life as measured by a validated instrument, nor tinnitus intrusiveness.Other adverse effects that were reported were not treatment-related.

AUTHORS' CONCLUSIONS

There is an absence of evidence to suggest that betahistine has an effect on subjective idiopathic tinnitus when compared to placebo. The evidence suggests that betahistine is generally well tolerated with a similar risk of adverse effects to placebo treatments. The quality of evidence for the reported outcomes, using GRADE, ranged from moderate to very low.If future research into the effectiveness of betahistine in patients with tinnitus is felt to be warranted, it should use rigorous methodology. Randomisation and blinding should be of the highest quality, given the subjective nature of tinnitus and the strong likelihood of a placebo response. The CONSORT statement should be used in the design and reporting of future studies. We also recommend the development of validated, patient-centred outcome measures for research in the field of tinnitus.

Sound therapy (using amplification devices and/or sound generators) for tinnitus

BACKGROUND

Tinnitus affects 10% to 15% of the adult population, with about 20% of these experiencing symptoms that negatively affect quality of life. In England alone there are an estimated ¾ million general practice consultations every year where the primary complaint is tinnitus, equating to a major burden on healthcare services. Clinical management strategies include education and advice, relaxation therapy, tinnitus retraining therapy (TRT), cognitive behavioural therapy (CBT), sound enrichment using ear-level sound generators or hearing aids, and drug therapies to manage co-morbid symptoms such as insomnia, anxiety or depression. Hearing aids, sound generators and combination devices (amplification and sound generation within one device) are a component of many tinnitus management programmes and together with information and advice are a first line of management in audiology departments for someone who has tinnitus.

OBJECTIVES

To assess the effects of sound therapy (using amplification devices and/or sound generators) for tinnitus in adults.

SEARCH METHODS

The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL, via the Cochrane Register of Studies); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 23 July 2018.

SELECTION CRITERIA

Randomised controlled trials (RCTs) recruiting adults with acute or chronic subjective idiopathic tinnitus. We included studies where the intervention involved hearing aids, sound generators or combination hearing aids and compared them to waiting list control, placebo or education/information only with no device. We also included studies comparing hearing aids to sound generators, combination hearing aids to hearing aids, and combination hearing aids to sound generators.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Our primary outcomes were tinnitus symptom severity as measured as a global score on multi-item tinnitus questionnaire and significant adverse effects as indicated by an increase in self-reported tinnitus loudness. Our secondary outcomes were depressive symptoms, symptoms of generalised anxiety, health-related quality of life and adverse effects associated with wearing the device such as pain, discomfort, tenderness or skin irritation, or ear infections. We used GRADE to assess the quality of evidence for each outcome; this is indicated in italics.

MAIN RESULTS

This review included eight studies (with a total of 590 participants). Seven studies investigated the effects of hearing aids, four combination hearing aids and three sound generators. Seven studies were parallel-group RCTs and one had a cross-over design. In general, risk of bias was unclear due to lack of detail about sequence generation and allocation concealment. There was also little or no use of blinding.No data for our outcomes were available for any of our three main comparisons (comparing hearing aids, sound generators and combination devices with a waiting list control group, placebo or education/information only). Data for our additional comparisons (comparing these devices with each other) were also few, with limited potential for data pooling.Hearing aid only versus sound generator device onlyOne study compared patients fitted with sound generators versus those fitted with hearing aids and found no difference between them in their effects on our primary outcome, tinnitus symptom severity measured with the Tinnitus Handicap Inventory (THI) at 3, 6 or 12 months (low-quality evidence). The use of both types of device was associated with a clinically significant reduction in tinnitus symptom severity.Combination hearing aid versus hearing aid onlyThree studies compared combination hearing aids with hearing aids and measured tinnitus symptom severity using the THI or Tinnitus Functional Index. When we pooled the data we found no difference between them (standardised mean difference -0.15, 95% confidence interval -0.52 to 0.22; three studies; 114 participants) (low-quality evidence). The use of both types of device was again associated with a clinically significant reduction in tinnitus symptom severity.Adverse effects were not assessed in any of the included studies.None of the studies measured the secondary outcomes of depressive symptoms or depression, anxiety symptoms or generalised anxiety, or health-related quality of life as measured by a validated instrument, nor the newly developed core outcomes tinnitus intrusiveness, ability to ignore, concentration, quality of sleep and sense of control.

AUTHORS' CONCLUSIONS

There is no evidence to support the superiority of sound therapy for tinnitus over waiting list control, placebo or education/information with no device. There is insufficient evidence to support the superiority or inferiority of any of the sound therapy options (hearing aid, sound generator or combination hearing aid) over each other. The quality of evidence for the reported outcomes, assessed using GRADE, was low. Using a combination device, hearing aid or sound generator might result in little or no difference in tinnitus symptom severity.Future research into the effectiveness of sound therapy in patients with tinnitus should use rigorous methodology. Randomisation and blinding should be of the highest quality, given the subjective nature of tinnitus and the strong likelihood of a placebo response. The CONSORT statement should be used in the design and reporting of future studies. We also recommend the use of validated, patient-centred outcome measures for research in the field of tinnitus.