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21/552 Microsuction compared with irrigation to remove earwax commissioning brief



The aim of the Health Technology Assessment (HTA) Programme is to ensure that high quality research information on the clinical effectiveness, cost-effectiveness and broader impact of healthcare treatments and tests are produced in the most efficient way for those who plan, provide or receive care from NHS and social care services. The commissioned workstream invites applications in response to calls for research on specific questions which have been identified and prioritised for their importance to the NHS, patients and social care.

Research question

What is the clinical and cost-effectiveness of microsuction compared with irrigation to remove earwax?

  • Intervention: Earwax removal by microsuction. 
  • Patient group: Adults with earwax requiring removal (Applicants to specify and justify).
    Applications are encouraged which include recruitment from geographic populations with high disease burden which have been historically underserved by research activity in this field.
  • Setting: Primary care, community, and any other suitable setting. 
  • Comparator: Earwax removal by irrigation.  
  • Study design: A pragmatic randomised controlled trial and cost-effectiveness analysis with an internal pilot phase to test key trial processes such as recruitment and adherence. Clear stop/go criteria should be provided to inform progression from pilot to full trial. 
  • Important outcomes: Wax-related measures (as defined by NICE NG98); need for additional interventions; quality of life; adverse effects; cost-effectiveness in different settings.
  • Other outcomes: Time to recurrence; any onward referral; patient acceptability.
    Where established Core Outcomes exist, they should be included amongst the list of outcomes unless there is good reason to do otherwise.  
  • Minimum duration of follow-up: 12 months.
  • Longer-term follow up: If appropriate, researchers should consider obtaining consent from participants to allow potential future follow up through efficient means (such as routine data) as part of a separately funded study.


A build-up of earwax in the ear canal can cause hearing loss and discomfort and may contribute to infections. Moreover, wax in the ear canal may prevent adequate clinical examination of the ear, thereby delaying assessment and management of ear or hearing problems.

Excessive earwax is common, especially in older adults and those who use hearing aids or earbud-type earphones. In the UK, it is estimated that 2.3 million people each year have problems with earwax sufficient to need intervention (see NICE guidance NG98).

Earwax is usually treated initially with eardrops. If this is unsuccessful, the wax can be removed using irrigation or microsuction. Irrigation equipment is inexpensive and widely available. However, the procedure is not always successful, which may result in re-interventions or referral to specialist services. Potential adverse events include damage to the ear canal or eardrum, and ear infections, and there are various contraindications that make irrigation unsuitable for some patient groups. Microsuction is currently more common in specialist settings, where it may be delivered by nurses or ENT specialists, but it is increasingly available in community settings and private earwax services. The equipment is more costly than irrigation devices. However, the intervention is faster than irrigation and success rates are higher, which may result in fewer re-interventions. Noise levels of the suction are high, but noise-induced adverse effects are usually mild and reversible.

There is a lack of evidence comparing these techniques in terms of clinical and cost-effectiveness. The NICE guideline committee thought it important that research is undertaken to investigate whether patients with earwax should be treated using irrigation or microsuction. The research could inform future clinical guidance and aid decision-making for patients, clinicians, and commissioners.

Additional commissioning brief background information

A background document is available that provides further information to support applicants for this call. It is intended to summarise what prompted the call and the existing evidence base, including relevant work from the HTA and wider NIHR research portfolio. It was researched and written on the basis of information from a search of relevant sources and databases, and in consultation with a number of experts in the field. If you would like a copy please email

Making an application

If you wish to submit a Stage 1 application for this call, the online application form can be found on the funding opportunities page. To select this call, use the filters on the right of the screen or search using the call name and/or number.

Your application must be submitted on-line no later than 1pm on the 1 December 2021. Applications will be considered by the HTA Funding Committee at its meeting in January 2022.

Guidance notes and supporting information for HTA Programme applications are available by clicking the links.

Important: Shortlisted Stage 1 applicants will be given eight weeks to submit a Stage 2 application. The Stage 2 application will be considered at the Funding Committee in May 2022.

Applications received electronically after 1300 hours on the due date will not be considered.

For commissioned topics, the Programme strongly discourages the practice of the same co-applicant joining more than one competing team. There may be unusual circumstances where the same person could be included on more than on application eg a lead from a named charity or a unique national expert in a condition.

For such exceptions (i) each application needs to state the case as to why the same person is included (ii) the shared co-applicant should not divulge application details between teams and (iii) both teams should acknowledge in their application that they are aware that one of their co-applicants is part of a competing application and that study details have not been shared.

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