| Class | Definition |
|---|---|
| I | High quality 1. Data from at least 2 good quality studies with ? 50 patients per study AND 2. Assessment of both main endpoints (differences UIA vs RIA AND IA vs control vessel) AND 3. Non-conflicting results from good quality studies |
| II | Moderate quality 1. Evidence including data from at least 2 good quality studies with ? 50 patients (in sum) AND 2. Assessment of both main endpoints (differences UIA vs RIA AND IA vs. control vessel) AND 3. Non-conflicting results from good quality studies |
| III | Low quality Summary data from: 1. >=100 patients regardless the study quality OR 2. >=50 patients from good quality studies |
| IV | Very low quality Any lower evidence for analyzed histological marker |
