Characteristics and costs for six studies conducted using VQI registry data versus counterfactual estimates
| Characteristics | Mean±SD per study |
| Number of subjects | 169±83 |
| Number of centers | 30±9 |
| Years of follow-up | 4.5±1.2 |
| Number of in-person evaluations | 5.3±1.5 |
| Number of imaging evaluations | 8.7±4.9 |
| Costs | |
| Six counterfactual studies | US$4 443 341±US$1 738 862 |
| Six VQI-based studies | US$1 825 599±US$815 692 |