Table 2. GRADE evidence profile for case–control studies on the association between surgical procedures and incidence of Creutzfeldt–Jakob disease .
| Type of surgery | Risk of bias | Inconsistency (I 2) | Indirectness | Imprecision | Publication bias |
High magnitude/ strength |
Dose-response relationship |
No residual confusion |
Overall quality of evidence |
|---|---|---|---|---|---|---|---|---|---|
| Cardiovascular surgery | Yes | Yes (55%) | No | No | Not assessed | No | No | No | Very low |
| Vascular surgery | Yes | Yes (63%) | No | No | Suspected | No | No | No | Very low |
| Eye surgery | Yes | Yes (72%) | No | Yes | Suspected | No | No | No | Very low |
| Time between surgery and diagnosis >20 years | No | Not applicable | No | No | Not applicable | No | Yes | No | Not applicable |
| Appendectomy | Yes | No (38%) | No | No | Not assessed | No | No | No | Very low |
| Tonsillectomy | Yes | Yes (73%) | No | Yes | Not assessed | No | No | No | Very low |
| Dental surgery | Yes | Yes (72%) | No | Yes | Not assessed | No | No | No | Very low |
| Gall bladder | Yes | Yes (64%) | No | Yes | Not assessed | No | No | No | Very low |
| Neurosurgery | Yes | No (52%) | No | Yes | Not suspected | No | No | No | Very low |
| Any surgery | Yes | Yes (66%) | No | Yes | Not suspected | No | Yes | No | Very low |
GRADE: Grading of Recommendations Assessment, Development and Evaluation [16].