Rating surgical field quality in endoscopic ear surgery: proposal and validation of the "Modena Bleeding Score".

To develop and validate a bleeding score that could be applied in endoscopic ear surgery (EEarS). A prospective validation study was performed. A new bleeding score, called "Modena Bleeding Score" (MBS), was created by the authors. It provides five grades for rating the surgical field during EEarS procedures (from grade 1-no bleeding to grade 5-bleeding that prevents every surgical procedure except those dedicated to bleeding control). A preliminary "face validity" was performed by 18 ENT specialists to assess possible misunderstandings in interpreting the scale. Then, 15 videos of endoscopic ear surgery procedures, each divided into three parts (t0, t1, and t2), were subsequently evaluated by 15 specialists, using MBS. The videos were randomly selected and assigned. Intra-rater reliability and inter-rater reliability were calculated. The clinical validity of the instrument was calculated using a referent standard (i.e., four ENT experts whose ratings were compared to those obtained by the former sample). The face validity showed a good consensus about the clarity and comprehension of the scale; both intra and inter-rater reliability demonstrated good performance (intra-rater reliability ranged from 0.741 to 0.991 and inter-rater reliability was 0.790); clinical validity also showed positive values, ranging from 0.75 to 0.93. MBS has proved to be an effective method to rate surgical field during EEarS, with good-to-excellent performances. Its use would possibly help comparisons of groups in clinical trials or comparisons between studies.