Table 3

Summary of results, overall effect sizes, and heterogeneity

Intervention comparisonOutcomekRR (95% CI)*, MD (95% CI)**NNT (95% CI) (NNT, NNT)Heterogeneity of outcome effects, summary statistics†
Fixed effectsRandom effectsτ2χ2I2 (%)P value
Hydrogel vs gauze (comparison 6)
 6.1Proportion of amputations (2 studies, 60 part)20.26 (0.05 to 1.37)0.26 (0.05 to 1.40)8 (3 to 12) (NNTB, NNTH)0.000.1100.74
 6.2Proportion of infections (3 studies, 198 part)30.87 (0.54 to 1.40)0.74 (0.18 to 2.99)12 (3 to 6) (NNTB, NNTH)0.914.89590.09
 6.3Proportion of ulcers healing (3 studies, 198 part)31.68 (1.14 to 2.49)*1.71 (1.16 to 2.52)*12 (50 to 3) (NNTB, NNTB)0.000.9500.62
Foam vs wet to dry (comparison 10)
 10.1Proportion of ulcers healing (2 studies, 37 part)24.35 (1.33 to 14.29)*3.56 (0.93 to 13.66)2 (2 to 5) (NNTB, NNTB)0.181.15130.28
Hydrofiber vs gauze (comparison 13)
 13.1Proportion of amputations (2 studies, 229 part)21.31 (0.33 to 5.16)1.34 (0.29 to 6.10)100 (15 to 15) (NNTB, NNTH)0.051.0330.31
 13.2Proportion of infections (2 studies, 229 part)21.11 (0.84 to 1.46)0.96 (0.40 to 2.31)50 (4 to 5) (NNTB, NNTH)0.211.37270.24
 13.4Proportion of ulcers healing (2 studies, 229 part)21.13 (0.92 to 1.38)15 (6 to 20) (NNTB, NNTH)0.000.0900.76
 13.5Mean time to complete healing (2 studies, 229 part)2−13.87
(−27.91 to 0.16)
−53.37
(−153.29 to 46.56)
4892.2316.2994<0.0001
Any debridement vs gauze (comparison 19)
 19.1Proportion of amputations (5 studies, 443 part)50.49 (0.19 to 1.27)0.48 (0.17 to 1.37)50 (15 to 34) (NNTB, NNTH)0.002.6700.75
 19.2Proportion of infections (7 studies, 659 part)71.10 (0.89 to 1.36)1.07 (0.76 to 1.52)50 (9 to 12) (NNTB, NNTH)0.0710.82350.15
 19.3aProportion of ulcers healing (11 studies, 798 part.)101.17* (1.00 to 1.36)1.22* (1.04 to 1.44)10 (5 to 100) (NNTB, NNTB)0.0213.89280.18
 19.3bProportion of ulcers healing (excluding two studies available only as abstracts) (9 studies, 728 part.) 91.12 (0.95 to 1.32)1.18 (0.99 to 1.41)12 (6 to 50) (NNTB, NNTH)0.0212.26350.14
 19.4Quality 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)
0.000.0000.95
 19.5Mean time to complete healing (4 studies, 458 part)42.54*
(1.20 to 3.87)
−27.88*
(−52.53 to −3.23)
614.4039.3390<0.00001
 19.6Proportion of ulcer recurrence (2 studies, 357 part)20.77 (0.34 to 1.71)0.81 (0.25, 2.58)100 (10 to 13) (NNTB, NNTH)0.423.29390.19
  • *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.