Ophthalmic nurse practitioner assessment of glaucoma: evaluating agreement within an initiative to enhance capacity in glaucoma clinics

Aims: A local service evaluation was conducted in order to compare clinical assessment measures and management decisions between an ophthalmic nurse practitioner and a reference standard glaucoma consultant, for patients referred into secondary care with suspected Chronic Open Angle Glaucoma or Ocular Hypertension. Methods: One hundred patients were selected. A clinical pathway incorporating the assessment methods recommended by National Institute for Health and Care Excellence (NICE) Glaucoma update 2017 (NG81) was delivered by a single ophthalmic nurse practitioner and the reference standard glaucoma consultant. Clinical findings and outcomes were recorded, with both practitioners being masked to each other’s findings. Agreement was determined employing Cohen’s kappa, measuring inter-rater agreement allowing for chance agreement. Results: Agreement was observed as follows: Visual field assessment (kappa k = 0.806, 95% CI 0.661–0.951); Optical Coherence Tomography evaluation (kappa k = 0.648, 95% CI 0.507–0.798); C:D Ratio assessment (Cronbach’s alpha α = 0.96, 95% CI 0.88–0.94); Diagnosis (kappa k = 0.874, 95% CI 0.818–0.914); and Treatment planning (kappa κ = 0.844, 95% CI 0.733–0.955). In three cases the nurse practitioner judged the optic nerve to appear normal, where the reference standard examiner detected glaucoma and commenced treatment. Conclusion: This service evaluation demonstrates how an ophthalmic nurse practitioner with appropriate theoretical knowledge and practical training, can develop skills to reach a high level of agreement in patient assessment and management for those patients with suspected glaucoma. Within the limitations of a single centre and single practitioner evaluation, our findings provide evidence that this model of capacity expansion ought to merit wider consideration in secondary care glaucoma services.