Table 2 Variation in definition of outcomes in randomised controlled trials

Presence of pus in the wound or wound pain, tenderness or erythema of sufficient magnitude to interfere with the patients well-being or to prolong hospital stay or to require readmission for wound infection [41]

Discharge of pus from the wound [14, 42, 47]

Purulent material which drained either spontaneously or by surgical incision [43]

Pus or erythema in the wound [49]

Presence of gross purulent discharge with or without positive bacterial culture [53]

Purulent discharge or positive culture from wound [55]

Suppuration confirmed by spontaneous wound rupture, debridement or incision [56]

Peri-incisional cellulitis or seropurulent wound drainage, whether culture positive or not [60]

Local signs of inflammation plus positive bacterial culture [65]

Clinical wound evaluation score on post-operative day 1, 2 and 7 [76]

No formal definition (n = 31)

Clinical symptoms plus laboratory findings of inflammation plus a positive ultrasound examination [65]

Abscess within the abdominal cavity diagnosed at operation or by rectal examination, x-ray or ultrasound [56]

Collections of purulent material which drained either spontaneously or by surgical incision [43]

Deep abscess [42]

No formal definition (n = 38)

Duration of fever (maximum daily rectal temperature >101 °F) [43]

Duration of fever [47]

Incidence of post-op fever (rectal >101 °F) during first 3 post-operative days [49]

Duration of fever (>100 °F) [50]

Duration of fever (>101 °F) [51]

Mean daily temperature; incidence fever (>37.5 °C) on third post-operative day [54]

Duration of fever (>38.0 °C) [55]

Duration of fever (>37.0 °C) [57, 58]

Temperature on first post-operative day [60]

Incidence of persistent fever (>38.5 °C for >3 days) [63]

Incidence of post-operative fever [66]

Maximum daily temperature for first five post-operative days [1, 75, 83]

Temperature on day 4 of treatment; percentage afebrile by day 7 of treatment [78]

Duration of white cell count (WCC) >12,500/cm³ [43]

Pre-discharge WCC [51]

WCC on days 4 and 8 of treatment [78]

Duration of WCC >10 x 10⁹/L [58]

Resolution of leukocytosis [60]

Time to return to normal WCC [63]

Trend of WCC reduction [55]

WCC on post-operative days 1 and 2 [76]

Return to school [40, 65]

Resumption of normal activity [66]

Time away from normal activities (a combination of objective time periods (hospital length of stay, outpatient status with central venous catheter, and receiving intravenous antibiotics) and more subjective time periods (for example, outpatient with symptoms that limit activity)) [22]

Able to do full physical activity at 1 and 4 weeks [61]

Return to sport activities [65]

Days to full activity [26]

Visual cosmesis score on eighth post-operative day [34]

Parental dissatisfaction with cosmetic result at 10 and 90 days; assessment by surgeon (mean of two blinded assessors) using a visual analogue scale at 90 days [35]

Patient scar assessment questionnaire (validated in adults) at 6 weeks and 18 months [25]