Summary of findings 4. PTFE compared to PTFE with vein cuff for below‐knee femoro‐popliteal bypass surgery.
| PTFE compared to PTFE with vein cuff for below‐knee femoro‐popliteal bypass surgery | ||||||
| Patient or population: people with peripheral vascular disease requiring below‐knee femoro‐popliteal bypass surgery Setting: hospital Intervention: PTFE Comparison: PTFE with vein cuff | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of limbs (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with PTFE with vein cuff | Risk with PTFE | |||||
| Primary patency (24 months) |
Study population | OR 1.08 (0.58 to 2.01) | 182 (2 RCTs) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | Findings from two small trials were inconsistent so our confidence in the effect is limited and this may differ substantially from the estimate of the effect | |
| 626 per 1000 | 644 per 1000 (493 to 771) | |||||
| Primary patency (60 months) |
‐ | ‐ | ‐ | ‐ | ‐ | No studies comparing PTFE with and without a vein cuff for below‐knee bypass reported on primary patency at 60 months |
| Secondary patency (24 months) |
Study population | OR 1.22 (0.67 to 2.23) | 181 (2 RCTs) | ⊕⊝⊝⊝ VERY LOW 1 2 3 | Findings from two small trials were inconsistent so our confidence in the effect is limited and this may differ substantially from the estimate of the effect | |
| 557 per 1000 | 605 per 1000 (457 to 737) | |||||
| Limb salvage (24 months) |
Study population | OR 1.34 (0.72 to 2.49) | 196 (2 RCTs) | ⊕⊕⊝⊝ LOW 1 3 | Our confidence in the effect is limited and this may differ substantially from the estimate of the effect | |
| 266 per 1000 | 327 per 1000 (207 to 474) | |||||
| *The risk in the intervention group (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: Confidence interval; OR: Odds ratio; | ||||||
| GRADE Working Group grades of evidence High quality: We are very confident that the true effect lies close to that of the estimate of the effect Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect | ||||||
1 Downgraded due to serious risk of bias resulting from lack of blinding and poor randomisation techniques 2 Downgraded due to significant heterogeneity in studies 3 Downgraded due to imprecision because of the low number of participants and events