To the Editor:

The study by Bubb et al. [1] describing agreement between a glaucoma specialist and a nurse practitioner in the assessment of glaucoma in a single center in the UK, showed moderate to excellent levels of agreement between the two providers. The article has several limitations and assumptions that require further consideration to avoid misinterpretation as well as misuse of the information by decision makers.

First, as the authors acknowledged, glaucoma is one of the most challenging diagnosis in ophthalmology practice as well as a leading cause of blindness worldwide [2, 3]. Eye doctors are trained for several years with a specific curriculum and outcomes; while the nurse practitioner described in the article has taken a long road of training with research and other experiences to be able to perform at the described level. Without a clear and replicable pathway of training, it is unfair to pretend that nurse practitioners can provide glaucoma care.

Second, the sample size was made of 100 patients with a 3% failure rate to diagnose glaucoma. The authors assumed that this is a low rate, but they are not considering that this is only from a small sample of subjects. When calculating the binomial 95% confidence interval of this rate, we obtained a range from 0.62 to 8.52%. This range does not seem too small, neither when recalculating the potential number of misdiagnosed patients with a larger sample size. In addition, there is no information about within rater reliability, limiting the understanding of how accurate the evaluators were. Furthermore, the satisfaction survey did not provide any information about the intervention being assessed nor insight about the perception in case of a false negative diagnosis.

The nursing staff, with specialized training in ophthalmology, play a key role in eye care. They can help screen patients, evaluate vision, differentiate whether the reason for consultation is refraction or internal pathology of the eyeball, assist with follow-up of patients with an established management plan, educating the patient to improve compliance and reduce anxiety [4]. However, with current and provided evidence, persuade readers that nurse staff could diagnose glaucoma will remain difficult to achieve.