Construct Validity of the Chicken Crop Model in the Simulation of Laparoscopic Pyeloplasty

Abstract

We examined the construct validity (ability to discriminate between experienced and inexperienced subjects) of the chicken crop model in the simulation of laparoscopic pyeloplasty. Dead chickens were used. The chicken crop and esophagus were used to simulate the human renal pelvis and ureter, respectively. The chicken was positioned in a left lateral position within a pelvic trainer to simulate a right ureteropelvic junction. Fifteen subjects were divided into three groups according to their levels of previous laparoscopic experience. Each subject performed a laparoscopic pyeloplasty with the model using the dismembered Anderson-Hynes technique. Operative time and quality scores were recorded. One-way analysis of variance (ANOVA) was used to detect differences among the groups. A Tukey multiple-comparisons test was used to detect differences between individual groups. Those in the most experienced group completed the "laparoscopic pyeloplasty" in an average of 33.80 minutes and got an average quality score of 9.0. Those in the less experienced group averaged 55.20 minutes and 7.0, respectively, and those in the group with no experience averaged 92.60 minutes and 4.0, respectively. There were significant differences in operative time and quality scores between the groups as shown by the one-way ANOVA (P<0.001), and also between the individual groups as shown by the Tukey multiple-comparisons test. There was, however, no significant difference in quality scores between the most experienced group and the less experienced group. The chicken crop model exhibits good construct validity and, as such, can be used to reproduce the technical complexity of laparoscopic pyeloplasty.