GAPS-EUS: a new and reliable tool for the assessment of basic skills and performance in EUS among endosonography trainees.

Objective: Endosonography (EUS) is a useful but complex diagnostic modality which requires advanced endoscopy training and guidance by a supervisor. Since learning curves vary among individuals, assessment of the actual competence among EUS trainees is important.

Design/methods: We designed a novel assessment tool entitled Global Assessment of Performance and Skills in EUS (GAPS-EUS) for assessing skills among EUS trainees. Five quality indicators were marked on a five-grade scale by the supervisor (Observer Score) and by the trainee (Trainee Score). Trainees were included in two high-volume centres (Gothenburg, Sweden, and Bologna, Italy). Outcomes were feasibility, patient safety, reliability, and validity of GAPS-EUS in trainee-performed EUS procedures.

Results: Twenty-two EUS-trainees were assessed in a total of 157 EUS procedures with a completion rate of 157/157 (100 %) and a patient adverse event rate of 2/157 (1.3 %; gastroenteritis n=1, fever n=1). GAPS-EUS showed a high measurement reliability (Cronbach's alpha coefficient=0.87) and a high inter-rater reliability comparing the supervisor and the trainee (r=0.83, r=0.69, p<0.001). The construct of GAPS-EUS was verified by comparing low-level and high-level performance procedures and the content validity by recording that the EUS-FNA manoeuvre resulted in a lower score than other aspects of EUS 3.07 (95% CI 2.91 to 3.23) vs 3.51 (95% CI 3.37 to 3.65) (p<0.001). External validity was confirmed via similar findings in both centres.

Conclusion: GAPS-EUS is an easy-to-use and reliable tool with a recorded high validity for the assessment of competence among trainees in EUS. It can be recommended to centres involved in the education of future endosonographers.

Trial Registration Number: NCT02455570.