The Face, Content, and Construct Validity Assessment of a Focused Assessment in Sonography for Trauma Simulator

ObjectiveHemorrhage identification in trauma care is a major priority. Focused assessment in sonography for trauma (FAST) offers a rapid, reliable means of detecting torso bleeding. The aims of this study were to conduct a face, content, and construct validity assessment of a FAST simulator and establish a rigorous assessment tool.DesignParticipants were requested to perform a FAST scan and state if any abnormality was found in each region. Metrics evaluated included time, errors, and missed targets. Accuracy of images obtained was assessed by 2 independent radiologists. Experts completed a face and content validity questionnaire at the end of the study.SettingThe study took place in the simulation suite within the Academic Surgical Unit of the Department of Surgery and Cancer.ParticipantsNovices had no prior experience with ultrasound, intermediates had less than 6 months experience with fewer than 50 FAST scans performed, and experts had more than 1 year of experience with greater than 100 FAST scans performed. There were 31 participants: 11 experts, 10 intermediates, and 10 novices.ResultsThe face and content validity questionnaire scored high marks across all categories and achieved an overall median realism score of 8 ± 1.5 on a Likert scale. Experts performed the FAST scan faster with more accuracy and fewer errors than other cohorts (p < 0.001). Both the novices and intermediates were the slowest, least accurate, and either missed or made the most errors when scanning the lung bases and spleen.ConclusionsThis study has established the face, content, and construct validities of a FAST simulator, which could be used to accelerate training for novices. Additionally, it has demonstrated a rigorous method for FAST assessment, which has proven to be effective and in doing so addressed some of the criticisms leveled against it.