Cost-effectiveness analysis of confocal scan laser ophthalmoscope (HRT II) versus GDX for diagnosing glaucoma

PURPOSE: The aim of this study was to assess the cost-effectiveness of confocal scan laser ophthalmoscopy (HRT II) and compare it with scanning laser polarimetry (GDx) for diagnosing glaucoma. METHODS: A cost-effectiveness analysis was performed at two eye hospitals in Iran. The outcome was measured as the proportion of correctly diagnosed patients based on systematic review and Meta analysis. Costs were estimated at two hospitals that used the HRT II (Noor Hospital) and current diagnostic testing technology GDx (Farabi Hospital) from the perspective of the healthcare provider. The incremental cost-effectiveness ratio (ICER) was estimated on the base scenario. RESULTS: Annual average costs were estimated as 12.70 USD and 13.59 USD per HRT II and GDx test in 2012, respectively. It was assumed that 80% of the maximum feasible annual tests in a work shift would be performed using HRT II and GDx and that the glaucoma-positive (Gl+) proportion would be 56% in the referred eyes; the estimated diagnostic accuracies were 0.753 and 0.737 for GDx and HRT II, respectively. The incremental cost-effectiveness ratio (ICER) was estimated at USD44.18 per additional test accuracy. In a base sensitivity sampling analysis, we considered different proportions of Gl+ patients (30%–85%), one or two work shifts, and efficiency rate (60%–100%), and found that the ICER ranged from USD29.45to USD480.26, the lower and upper values in all scenarios. CONCLUSION: Based on ICER, HRT II as newer diagnostic technology is cost-effective according to the World Health Organization threshold of <1 Gross Domestic Product (GDP) per capita in Iran in 2012 (USD7228). Although GDx is more accurate and costly, the average cost-effectiveness ratio shows that HRT II provided diagnostic accuracy at a lower cost than GDx.