The eventual summary was defined by adding up weights assigned to each LoE. Sum of LoE → Final risk class: 0–2.5 → 0; 2.6–5.0 → 1; 5.1–7.5 →2; 7.5–10.0 → 3. Final weights and risk classes from 0 to 3 were ranked as negligible (+/−), low (+), moderate (++) or high (+++).
2.5. Statistical tests