Missed Opportunities in Screening for Glaucoma.

Purpose: To create a holistic and realistic view regarding current knowledge, understanding, and challenges of screening in general and in glaucoma.

Methods/results: Based upon available literature, all systems suffer from the same challenges: huge variability of care practices (despite guidelines), simultaneous under care and over care, as well as the unsustainable increase of costs. While the magnitude of these challenges differs immoderately between well-off and developing countries, the Western world has already demonstrated that simply doing more than what we currently do is not the solution. System outcomes also matter in screening, that is, its benefits should outweigh any harms (over-care, false positives/negatives, uncertain findings, etc.) and be cost-effective. However, even when the evidence does not support screening (as is currently the case in glaucoma), it may feel justified as "at least we are doing something." Strong commercial interests, lobbying and politics star as well and will influence the control arm even in high-quality randomized screening trials (RCT).

Conclusions: As resources will never be sufficient for all health care activities that providers wish to deliver and what people wish to receive, we need to ask big questions and adopt a public health perspective in glaucoma and eye care. How can we create and maintain a sustainable balance between finding and treating underserved high-risk patients without burdening the broader patient population and societies with over-diagnostics and treatments? Considering numerous biases related to screening, including the variability in care practices, a high-quality RCT for the screening of glaucoma would be very challenging to organize and evaluate its universal usefulness.