The aim of this study is to collect validity evidence for the ACTION-tool on two different simulators: a porcine rib model, and Thiel embalmed human cadavers. Validity evidence will be collected following Messick's framework.

Educational assessments need a validity argument before they are being used to evaluate trainees. An assessment needs to show it can be used as an objective and reliable tool.

Messick's framework of validity collects this evidence from five different sources: content, response process, relation to other variables, internal structure and consequences.

The ACTION-tool has been developed based on a Delphi consensus study (and has established content evidence as a result). This study will collect evidence from the four remaining sources.

Two groups of participants (novices and experienced) will be recruited. All participants will provide informed consent and demographic information. Afterwards, they will be informed of the study, will familiarise themselves with the simulators, watch an educational video, and will be asked to perform two chest tube insertions (CTI).

All participants will be evaluated by a live rater, and will be recorded using a head-mounted GoPro and an overview camera. The recordings will be edited to ensure anonymization, and will be subsequently rated by three blinded raters.

Statistical analysis will evaluate the difference in mean scores between the groups, the internal structure using G-theory, and will establish a pass/fail score.

Inclusion Criteria:

• Experienced participants must hold a degree of Master in Medicine, and must have finished the residency training specific to their field (attending physician).
• Novice participants are defined as junior residents who are graduated as Master in Medicine and must be in their first two years of residency training, or be at least in their 3rd Master year of Medicine and be accepted as starting resident.

Exclusion Criteria:

• Experienced participants who lack experience or the appropriate diplomas will be excluded.
• Novices who have performed more than five CTI or assisted in the placement of more than five procedures will be excluded.

All participants will be recruited from Ghent University Hospital. Experienced participants are faculty members, and the novice group is recruited from the resident population.