Summary of findings for the main comparison. NPWT compared with dressings for postoperative foot wounds in people with diabetes mellitus.
| NPWT compared with dressings for postoperative wounds | ||||||
|
Patient or population: treating foot wounds in people with diabetes mellitus Setting: hospital Intervention: NPWT Comparison: dressings | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with placebo | Risk with NPWT compared with dressings | |||||
|
Proportion of wounds healed Follow‐up: 16 weeks |
Study population | RR 1.44 (1.03 to 2.01) | 162 (1 study) |
⊕⊕⊝⊝ Lowa,b |
— | |
| 388 per 1000 | 559 per 1000 (400 to 780) | |||||
|
Time to healing Follow‐up: 16 weeks |
Study population | HR 1.91 (1.21 to 2.99) | 162 (1 study) |
⊕⊕⊝⊝ Lowa,b |
— | |
| 388 per 1000 | 609 per 1000 (448 to 770) | |||||
|
Amputations Follow‐up: 16 weeks or unspecified |
Study population | RR 0.38 (0.14 to 1.02) | 292 (2 studies) |
⊕⊝⊝⊝ Very lowa,c |
— | |
| 60 per 1000 | 23 per 1000 (8 to 61) | |||||
| Number of wounds closed or covered with surgery | 954 per 1000 | 1000 per 1000 (238 to 1000) | RR 1.02 (0.95 to 1.09) | 130 (1 study) |
⊕⊝⊝⊝ Very lowa,c |
— |
|
Adverse events Follow‐up: 16 weeks |
Study population | RR 0.96 (0.72 to 1.28) | 162 (1 study) |
⊕⊝⊝⊝ Very lowa,c |
— | |
| 541 per 1000 | 520 per 1000 (390 to 693) | |||||
| Cost‐effectiveness | Not estimable | Not estimable | Not estimable | Not estimable | Not estimable | — |
| Wound recurrence | Not estimable | Not estimable | Not estimable | Not estimable | Not estimable | — |
| *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; NPWT: negative pressure wound therapy; RR: risk ratio. | ||||||
| GRADE Working Group grades of evidence High certainty: we are very confident that the true effect lies close to that of the estimate of the effect. Moderate certainty: 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 certainty: our confidence in the effect estimate is limited: the true effect may be substantially different from the estimate of the effect. Very low certainty: we have very little confidence in the effect estimate: the true effect is likely to be substantially different from the estimate of effect. | ||||||
aDowngraded one level due to risk of bias: some blinded outcome assessment, but not sure the potential impact of non‐blinded decisions regarding the use of further surgery and the risk of performance bias. bDowngraded one level due to imprecision: small sample size and wide 95% confidence intervals. cDowngraded two levels due to imprecision: few events and 95% confidence intervals around effects included both appreciable benefit and appreciate harm.