Utility gains and cost per QALY results based on published evidence (INR 2016)
| Utility calculation | Sharma et al 22 | Brown et al 23 | Brown et al 24 | Sharma et al 25 | ||
| Utility improvement based on improvements in VA (utility of improved state less initial utility) | =0.84–0.62=0.22 | Using time trade off method=0.89–0.57=0.32 | Using standard gamble=0.96–0.69=0.27 | =0.97–0.76=0.21 | Using time trade off method=0.908–0.708=0.2 | Using standard gamble=0.948–0.769=0.179 |
| Incremental cost per QALY of RMS versus no intervention (INR 2016) | ||||||
| If spectacles lasted 1 year | 925 | 636 | 754 | 969 | 1018 | 1137 |
| If spectacles lasted 2 years* | 463 | 318 | 377 | 485 | 509 | 569 |
| If spectacles lasted 3 years* | 308 | 212 | 251 | 323 | 339 | 379 |
*Future benefits discounted at a rate of 3% per year as recommended.18
INR, Indian rupee; RMS, ready-made spectacles; VA, visual acuity.