Despite being effective, the majority of people who would benefit from using hearing aids do not access them. For those who do obtain hearing aids, around 20% do not wear them regularly. People often do not use their hearing aids because they continue to experience difficulties when listening to and understanding speech in noisy situations.

Conventional hearing aids must be programmed and adjusted by a trained audiologist with specialist equipment and therefore provide limited user-control over the hearing aid's functionality. In comparison to conventional hearing aids, Smartphone-connected hearing aids enable patients to adjust their programmes themselves in different situations using a Smartphone application. Smartphone-connectivity can supplement clinical practices, as patients can adjust their hearing aids without the need to visit the clinic. This has the potential to empower patients to be actively involved in their own hearing healthcare.

A systematic review assessing the effectiveness of alternative listening devices showed that there is no published high-quality research assessing the clinical effectiveness of Smartphone-connected hearing aids. Furthermore, a usability research study has shown that patients want to personalise and adjust their own HA programmes to meet their individual needs. Having carried out the early development work, the next step would be to carry out a study to evaluate smartphone-connected hearing aids, in accordance with the MRC guidelines on developing and evaluating complex interventions.

This study will assess the benefits of a smartphone application, eAdjust that has been developed for use with Phonak Audeo B90-Direct hearing aids. The eAdjust app connects to the hearing aid via Bluetooth, and enables hearing aid users to fine-tune their hearing aids via their smartphone. The benefits of the eAdjust app will be assessed in the real-world as well as in the laboratory. A mixed methods approach will be taken, using both behavioural and patient reported outcomes.

Inclusion Criteria:

• Adults aged ≥18 years.

• With hearing loss type: symmetric (not more than 20 dB difference) and sensorineural.

• With mild to severe hearing loss in the categories: N2, N3, N4, N5, S2 and S3.

• No disturbing tinnitus.

• No contraindications against wearing hearing aids (e.g. ear disease or motor impairment).

• Hearing aid user:

  1. First-time (using hearing aids < 3 months)
  2. Existing (using hearing aids > 6 months)

• Owns an iPhone (v5 and IOS 10 or higher) and uses functions of her/his smartphone which exceed calling and writing text messages.

• Willing to wear test hearing aids, to use the eAdjust App, to take notes about experiences and to perform various tasks during the study period.

• English as a first spoken language or a good understanding of English. It is important that participants can understand the content of the resources and work with the interactive elements, as well as be able to answer outcome questionnaires, to ensure valid data are collected.

Exclusion Criteria:

- Unable to complete the questionnaires without assistance due to age-related problems (e.g. cognitive decline or dementia), to ensure valid data are collected.

Hearing aid users (first-time and existing) will be recruited from Nottingham Audiology Adult Service, Nottingham University Hospitals NHS Trust (secondary care). Immediately following the patient's hearing assessment appointment, a member of the patient's usual care team (audiologist) will identify eligible patients.