Validation of virtual reality simulation for obstetric ultrasonography: a prospective cross-sectional study

Ultrasonography is an important skill for obstetricians and gynecologists; however, trainees have highlighted ultrasonography as an area of deficiency in their training. We undertook a prospective cross-sectional comparative study to assess content and construct validity of an ultrasound virtual reality (VR) simulator (UltraSim).

Twenty-six physicians and sonographers of varied ultrasonography experience were recruited and divided into trainees (no formal ultrasonography training) and expert (certified) categories. They performed a VR simulation crown-rump length (CRL) ultrasound scan and growth ultrasound scan measuring biparietal diameter, occipitofrontal diameter, abdominal anteroposterior and transverse diameters, and femur length. Maximum pool depth (MPD), placental site, and fetal presentation were also assessed. Outcome measures included the mean absolute deviation and the variance of the absolute deviation from true measurements. Accuracy of determining placental site, fetal presentation, and MPD was assessed. The time taken to perform each type of scan was recorded.

Trainees had significantly greater variation of measurement of CRL (P = 0.025) than the expert group. For late-pregnancy fetal biometry, the absolute deviation and the degree of variability for all measurements differed. These differences were statistically significant (P < 0.05) for all measurements except abdominal diameters and MPD. Trainees took significantly longer time to obtain CRL and fetal biometric scans (P < 0.001). All subjects correctly identified fetal presentation and placental site.

Clinicians with differing ultrasonography expertise showed differing skill with the UltraSim VR simulator, demonstrating construct validity for skills needed in simulation. Consideration should be given to investigating whether trainees with minimal scanning experience can improve their clinical skills and efficiency with VR simulation.