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Surgical performance of large loop excision of the transformation zone in a training model: A prospective cohort
Günther A Rezniczek1, Sofia Severin, Ziad Hilal
1Department of Obstetrics and Gynecology, Ruhr-Universität Bochum, Bochum Department of Obstetrics and Gynecology, St. Anna Hospital, Herne Department of Obstetrics and Gynecology, Klinikum Oldenburg, Carl von Ossietzky Universität Oldenburg, Oldenburg, Germany.
Abstract:
Large loop excision of the transformation zone (LLETZ) is one of the most common procedures in operative gynecology and it is a routine part of the surgical training program of residents. There is, however, no established and standardized method of teaching residents how to perform LLETZ. Here, we present a surgical training model and assessed the improvement of surgical skills during repeated hands-on trainings of LLETZ in this model.Surgical novices and experts were recruited and were shown a LLETZ training video and then performed 3 LLETZ training sessions on consecutive days. Surgical skills were assessed by Objective Structured Assessment of Technical Skills (OSATS). Global rating scale (GRS), confidence (CON), fragmentation rate (FR), performance time (PT), and OSATS scores were calculated. Intra- and interobserver variabilities were determined. The construct validity of OSATS was assessed comparing metric scores of novices with those of experts.Sixty-eight probands (58 novices, 10 experts) were recruited. GRS, 2.3 ± 1.3 (median ± SD) versus 1.4 ± 0.6, P < .001; CON, 2.7 ± 0.9 versus 1.6 ± 0.6, P < .001; FR, 81% versus 100%, P < .001; PT, 152 ± 33 versus 120 ± 27 seconds, P = .006; and OSATS scores, 18.8 ± 1.3 versus 19.1 ± 1.1, P = .16 of novices improved from session 1 to session 3. OSATS showed construct validity with metric scores (GRS, 1.1 ± 0.3 vs 2.3 ± 0.8, P < .001; CON, 1.0 ± 0.0 vs 2.7 ± 0.9, P < .001; PT 125 ± 30 vs 152 ± 33 seconds, P = .02; OSATS scores, 19.6 ± 0.7 vs. 18.8 ± 1.3, P = .02) reliably discriminating between experts and novices. Intra- and interobserver variabilities across probands were 0.99 ± 0.03 and 0.64 ± 0.10, respectively. OSATS scores were independent of handedness, sex, and regular sports activity in univariate and multivariate analyses.Repeated hands-on trainings improve surgical performance of LLETZ in a surgical training model with construct validity.

