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Outcomes for ophthalmic clinical trials requires consistent studies to ensure systematic reviews and decision-making

A number of researchers and clinicians suggest that consistent clinical trial outcome measures may benefit decision-making for clinical research across three ophthalmic studies – AMD, refractive error in children and dry eye. The researchers indicate that well designed and rigorous randomized controlled trials (RCTs) should provide the basic tools for presenting systematic reviews and best patient care. The researchers that identify core assessments of outcomes believe to be important to capture all relevant stakeholders. In summary, researchers suggest that RCT results need to be actionable if they can be used for systematic reviews, namely: (a) the use of defined consistently tools across RCTs, and; (b) addressing the needs of stakeholders and patients when bundled across many clinical trial studies.


The study shows in the analysis of many reviews that there has been inconsistent outcomes within RCTs and that many of the outcomes appear not to be relevant for stakeholders. In terms of inconsistencies, a meta-analysis across several studies may only include a few or no RCT results, showing that is difficult to build useful systematic studies. A 2016 Cochrane systematic review has shown for over-the-counter tear drops for dry eye have only 4 of 43 eligible RCTs incapable to have a sufficient meta-analysis for the research. When studies are assessed it has shown that dry eye had as many as 105 unique outcomes in 138 RCTs, which makes it impossible to compare across several independent researchers. A further example is also shown to be have 107 unique outcomes in 79 RCTs for age-related macular degeneration. In short, it is extremely difficult to methodically compare the required types of outcome measures. Similar outcomes have been reported in such unique measures in other disorders including cataract, diabetic retinopathy, glaucoma, uveitis, allergic conjunctivitis and intermittent exotropia.


Aside from the academic analysis for medical outcomes, there also may be difficulties for researchers to understand what to be used for patient reimbursement decisions. To study the process, researchers are hoping to standardize outcomes in ophthalmology and recently have chosen three prevalent conditions to assess these trials including AMD (with an estimated prevalence, 1.5%), refractive error in children (prevalence between 1% to 26%) and dry eye (prevalence between 7% to 33%). The researchers aim to set up “core outcome sets” (COSs) and state that, “[c]ore outcome set development presents major opportunities. First, engaging various stakeholders encourages collaboration and mutual exchange of ideas. Second, COS development offers funders the opportunity to influence the outcomes measured in the research they support. Third, COSs help to streamline the design of pivotal RCTs to bring new products to market”. Most notably, the researchers have commented that “[a]ctionable outcomes require consistency across RCTs and must address the needs of stakeholders, including patients. The existence of an agreed-on COS eventually enables treatment guidelines to be informed by comprehensive and accurate estimates of effectiveness and safety.”