Summary of results, overall effect sizes, and heterogeneity
| Intervention comparison | Outcome | k | RR (95% CI)*, MD (95% CI)** | NNT (95% CI) (NNT, NNT) | Heterogeneity of outcome effects, summary statistics† | ||||
| Fixed effects | Random effects | τ2 | χ2 | I2 (%) | P value | ||||
| Hydrogel vs gauze (comparison 6) | |||||||||
| 6.1 | Proportion of amputations (2 studies, 60 part) | 2 | 0.26 (0.05 to 1.37) | 0.26 (0.05 to 1.40) | 8 (3 to 12) (NNTB, NNTH) | 0.00 | 0.11 | 0 | 0.74 |
| 6.2 | Proportion of infections (3 studies, 198 part) | 3 | 0.87 (0.54 to 1.40) | 0.74 (0.18 to 2.99) | 12 (3 to 6) (NNTB, NNTH) | 0.91 | 4.89 | 59 | 0.09 |
| 6.3 | Proportion of ulcers healing (3 studies, 198 part) | 3 | 1.68 (1.14 to 2.49)* | 1.71 (1.16 to 2.52)* | 12 (50 to 3) (NNTB, NNTB) | 0.00 | 0.95 | 0 | 0.62 |
| Foam vs wet to dry (comparison 10) | |||||||||
| 10.1 | Proportion of ulcers healing (2 studies, 37 part) | 2 | 4.35 (1.33 to 14.29)* | 3.56 (0.93 to 13.66) | 2 (2 to 5) (NNTB, NNTB) | 0.18 | 1.15 | 13 | 0.28 |
| Hydrofiber vs gauze (comparison 13) | |||||||||
| 13.1 | Proportion of amputations (2 studies, 229 part) | 2 | 1.31 (0.33 to 5.16) | 1.34 (0.29 to 6.10) | 100 (15 to 15) (NNTB, NNTH) | 0.05 | 1.03 | 3 | 0.31 |
| 13.2 | Proportion of infections (2 studies, 229 part) | 2 | 1.11 (0.84 to 1.46) | 0.96 (0.40 to 2.31) | 50 (4 to 5) (NNTB, NNTH) | 0.21 | 1.37 | 27 | 0.24 |
| 13.4 | Proportion of ulcers healing (2 studies, 229 part) | 2 | 1.13 (0.92 to 1.38) | 15 (6 to 20) (NNTB, NNTH) | 0.00 | 0.09 | 0 | 0.76 | |
| 13.5 | Mean time to complete healing (2 studies, 229 part) | 2 | −13.87 (−27.91 to 0.16) | −53.37 (−153.29 to 46.56) | 4892.23 | 16.29 | 94 | <0.0001 | |
| Any debridement vs gauze (comparison 19) | |||||||||
| 19.1 | Proportion of amputations (5 studies, 443 part) | 5 | 0.49 (0.19 to 1.27) | 0.48 (0.17 to 1.37) | 50 (15 to 34) (NNTB, NNTH) | 0.00 | 2.67 | 0 | 0.75 |
| 19.2 | Proportion of infections (7 studies, 659 part) | 7 | 1.10 (0.89 to 1.36) | 1.07 (0.76 to 1.52) | 50 (9 to 12) (NNTB, NNTH) | 0.07 | 10.82 | 35 | 0.15 |
| 19.3a | Proportion of ulcers healing (11 studies, 798 part.) | 10 | 1.17* (1.00 to 1.36) | 1.22* (1.04 to 1.44) | 10 (5 to 100) (NNTB, NNTB) | 0.02 | 13.89 | 28 | 0.18 |
| 19.3b | Proportion of ulcers healing (excluding two studies available only as abstracts) (9 studies, 728 part.) | 9 | 1.12 (0.95 to 1.32) | 1.18 (0.99 to 1.41) | 12 (6 to 50) (NNTB, NNTH) | 0.02 | 12.26 | 35 | 0.14 |
| 19.4 | Quality of Life (1 study divided into two separate subgroup analyses, 264 participants) | 1 | −0.01 (−0.04 to 0.01) | −0.01 (−0.04 to 0.01) | 0.00 | 0.00 | 0 | 0.95 | |
| 19.5 | Mean time to complete healing (4 studies, 458 part) | 4 | 2.54* (1.20 to 3.87) | −27.88* (−52.53 to −3.23) | 614.40 | 39.33 | 90 | <0.00001 | |
| 19.6 | Proportion of ulcer recurrence (2 studies, 357 part) | 2 | 0.77 (0.34 to 1.71) | 0.81 (0.25, 2.58) | 100 (10 to 13) (NNTB, NNTH) | 0.42 | 3.29 | 39 | 0.19 |
*Indicates a significant effect; part: participants; k represents the number of interventions for each outcome included in the analysis; Q represents Cochran’s Q, indicating significance of heterogeneity; I2 represents the magnitude of heterogeneity; p value represents the significance of heterogeneity.
†Relative risk (RR) was the effect estimate for the proportion of amputations, proportion of infections, proportion of ulcers healed, and proportion of recurrence. Mean difference (MD) was the effect estimate for the outcomes quality of life and time to complete healing.
‡ Mean Difference applies to comparison 13.5 Hydrofiber vs Gauze / Mean Time to Complete Healing; compaison 19.4 Hydrofiber vs Gauze / Quality of Life; and comparison 19.5 Any Debridement vs Gauze / Mean Time to Complete Healing.
NNT, number needed to treat; NNTB, number needed to treat for an additional beneficial outcome; NNTH, number needed to treat for an additional harmful outcome.