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

The effect of randomised controlled trials (RCTs) is diminished by inconsistent outcome reporting, precluding the efficient synthesis of data into systematic reviews and meta-analyses. Amblyopia, strabismus, and ocular motility disorder patients constitute a significant proportion of those seen in ophthalmology generally and in paediatric ophthalmology specifically, making efficient synthesis of research data a greater necessity. Core Outcome Sets (COS), defined as agreed standardised sets of outcomes that should be measured and reported, as a minimum, in all clinical trials in a health area, have been found to help with the problem of inappropriate and inconsistent outcomes. The objective of this research was to develop three COS for amblyopia, strabismus, and ocular motility disorders. The methods comprised a systematic review to identify reported outcomes and establish whether there was outcome reporting inconsistency as suggested by other studies; qualitative semi-structured focus group meetings with patients, carers and healthcare professionals to establish outcomes of their importance; and finally, a Delphi online survey and consensus meetings with stakeholders to reach agreement on what should be included in the COS. The systematic review, which included 142 trials, systematic reviews, and other studies, identified significant heterogeneity in outcome reporting, and populated the Delphi process with 24 outcomes for amblyopia, 47 for strabismus, and 68 for ocular motility disorders. The qualitative study reflected the fact that long-term outcomes and quality-of-life aspects are the greatest priority of patients and carers, and resulted in the addition of 7, 14, and 10 outcomes to the three conditions, respectively. Although consensus between stakeholders was not reached conclusively in the Delphi survey, it resulted in the identification of the most critical outcomes, which were then collapsed into nine to ten core outcomes in the consensus meetings, with significant overlap between the three conditions. All three conditions shared the core outcomes: adverse events, cost, vision-related quality of life, and ocular alignment. The strabismus and ocular motility disorder core sets included, in addition, patient satisfaction, symptoms, binocular vision, ocular movement, and deviation. The ocular motility disorders COS included clinical signs, additionally. The amblyopia set, distinct from the sets for the other two conditions, included best corrected distance and near visual acuity, compliance, refraction, and treatment-related and long-term impacts. Implementation of these COS will improve outcome consistency, which will facilitate the comparison and combination of clinical trials and therefore synthesis of their data into meta-analyses. Further consideration must be given to increasing the uptake of the COS to maximise its usefulness, and future work will be required to standardise methods and timings of measurements. Continuous review and update of the COS to match future new interventions may be required