Development of a core outcome set for clinical research and practice in amblyopia, strabismus and ocular motility disorders

We aim to establish three core outcome sets relevant to the treatment of amblyopia, strabismus and ocular motility disorders which primarily reflect the interests of patients but also clinicians, researchers and commissioners in order to facilitate decision-making by all stakeholders. Our research question is 'what are the core outcome measures deemed valid and important by patients, but also deemed relevant to healthcare providers?' Specific objectives are to 1) identify a list of outcomes previously reported by researchers and clinicians in studies of the treatment of amblyopia, strabismus and ocular motility disorders from a systematic review of the literature, determine the heterogeneity of outcome definitions, the number of differing measuring instruments used and the specific ways in which they differ, 2) identify outcomes from the perspective of patients in order to augment the list generated from (1), 3) determine the most appropriate method of measurement for each important outcome, 'how' the outcome is measured and 'when' to determine the outcome, and 4) prioritise and reach consensus regarding the most important outcomes from the perspectives of patients and clinicians into a core outcome set - the 'what'.


PI: Dr Samiya Al-Jabri, University of Liverpool
Supervisors: Dr Fiona Rowe and Dr Jamie Kirkham, University of Liverpool
Collaborators: Ms Carmel Noonan, Aintree University Hospital NHS Trust

Further Study Information

Current Stage: Ongoing
Date: June 2016 - May 2020
Funding source(s): Independent funded postgraduate degree (Oman)

Health Area

Disease Category: Eyes & vision

Disease Name: Strabismus, Amblyopia, Ocular motility disorders

Target Population

Age Range: 18 - 100

Sex: Either

Nature of Intervention: Any

Stakeholders Involved

- Clinical experts
- Consumers (caregivers)
- Consumers (patients)
- Journal editors
- Methodologists
- Policy makers
- Researchers
- Service providers
- Statisticians

Study Type

- COS for clinical trials or clinical research
- COS for practice


- Consensus meeting
- Delphi process
- Focus group(s)
- Literature review
- Nominal group technique (NGT)
- Systematic review

Research question: What are the outcomes reported in the published literature assessing the effectiveness of treatments for amblyopia, strabismus and ocular motility disorders.

Methods: We will conduct an overview of reviews inclusive of narrative and systematic reviews identified from a database search (medline, SCOPUS, Central, EMBASE, PSCHY, etc) and Cochrane systematic reviews (Eyes and Vision Cochrane group currently contains 17 full reviews and 6 protocols of relevance).

Inclusion criteria: Reviews of the literature that include intervention studies and/or diagnostic test accuracy studies for conditons of amblyopia, strabismus and ocular motility disorders. We will include any intervention that aims to improve the conditions of amblyopia, strabismus and ocular motility disorders or alleviate their associated visual symptoms. Interventions may include occlusion, optical penalisation, behavioural vision training, extra oclar muscle surgery, extra ocular muscle injection of botulinum toxin, pharmacology therapy for nystagmus. The review will be reported in accordance with PRISMA guidelines.

Methods: We will engage with patients and carers to determine if any additional items can be identified to supplement those determined from the systematic review. We will conduct semi-structured focus groups of thirty patients and carers (ten amblyopia, ten strabismus and ten ocular motility disorders) using a nominal group technique to gather information from the participants in a facilitated forum. This sample size is considered an appropriate number for qualitative research using focus group design (NIHR James Lind Alliance). Patients and carers will be identified from patient and public involvement groups linked with the participating University and NHS Trusts in addition to national groups linked with professional organisations such as the British and Irish Orthoptic Society (for which the lead applicant is the national Director of Research).

Methods: A survey of key stakeholder opinions using Delphi methodology will be conducted for all three conditions collectively. The list of potential outcomes finalised from Sections 1 and 2 will be formatted into ‘outcome items’ with a response designed to allow the participants to rate each of the outcomes value for potential inclusions into the final core outcome set, with higher scores indicating the importance of inclusion. An online questionnaire will be developed for the Delphi process by the IS Developer using the outcome measures identified from work sections 1 and 2. This will be piloted for each of the key stakeholder groups (patients, carers, clinicians, NHS managers and researchers). Clinicians, researchers and NHS managers will be identified through existent national and international professional bodies and networks. Patients and carers will be identified through patient and public involvement groups linked with the participating University and NHS Trusts in addition to national groups linked with professional organisations. We will aim for 30 participants across each group. Outcome items will be reworded into plain language suitable for each stakeholder groups, with help sought from our PPI collaborator for language suitable for patients. The design of the questionnaires for each group will also be carefully considered with inputs from the advisory group. It is anticipated that the Delphi process will consist of three rounds.