Agreement was assessed before and after reading the SSI definition JQ1 without distinguishing specialties or countries. To evaluate intra- and inter-specialty agreements for SSI diagnosis based on 1�C7 Likert scale scores, we computed the ICC with the 95%CIs. An ICC of 0 indicates the level of agreement produced by chance alone and an ICC of 1 indicates perfect agreement. We defined poor agreement as ICC values less than 0.4, good agreement as ICC values of 0.4 to 0.7, and very good agreement as ICC values greater than 0.7 [17]. To evaluate intra- and inter-specialty agreement regarding SSI depth scored on a 3-point scale, we computed the kappa coefficient with the 95%CIs. We added a fourth category comprising the participants who did not score SSI depth because their SSI diagnosis score was less than 4.

Agreement is considered poor when �� is 0.20 or less, fair when �� is 0.21�C0.40, moderate when �� is 0.41�C0.60, good when �� is 0.61�C0.80, and very good when kappa coefficient is 0.81�C1.00 [18]. Analyses were performed using SAS System, Version 9. 3 (SAS Institute, Cary, NC, USA). Results Characteristics of the Participants and Case-vignettes Overall, 100 ICPs and 86 surgeons agreed to participate; there were 10 surgeons from each of six countries and four to nine surgeons from the remaining four countries. The 186 participants worked in publicly funded (n=179) or private (n=7) healthcare facilities in 75 university and 57 non-university hospitals; of these 132 hospitals, 95 (72%) each contributed one participant, 35 (27%) two or three participants, and two (1%) five participants.

Median (IQR) age was 47 (40�C53) years, 117 (62.9%) participants were men, median time in the current job was 13 (7�C20) years, and 142 (76.3%) participants were directly involved in SSI surveillance programmes in their healthcare facility (Table S1). Table S2 reports the characteristics of the 20 patients selected to build the case-vignettes. SSI was suspected before hospital discharge in 11 patients and after hospital discharge in 9 patients who required re-admission. Wound modification was a feature in 12 (60%) patients. Microbiological specimens were obtained from the surgical wound in 15 patients and were positive in 13. As four countries contributed 14 fewer surgeons than expected, they contributed lower than expected scores.

In all, each of the 20 vignettes was scored without the SSI definitions 40 times by ICPs; for scoring by surgeons, 8 vignettes were scored 35 times, 5 were scored 33 times, 3 were scored 34 times, and 4 had miscellaneous numbers of scorings. In all, there were 1488 Cilengitide scorings without the SSI definitions, instead of the expected 1600. Case-vignette Scores In addition to the 1488 scorings without the SSI definitions, 14 vignettes were each scored four times and six vignettes three times with the SSI definitions, for a total of 74 scorings.