Role of biomedical knowledge in learning visual diagnosis

In the medical profession, biomedical knowledge (i.e., facts about (ab)normal functioning of the human body) forms the basis for expertise. This study investigated the role of biomedical knowledge in learning to examine information-dense, dynamic medical images, namely ultrasound fetal images. For this purpose, 33 medical students with biomedical knowledge background were compared to 44 human-movement science students with a knowledge background in the biomechanics of human movement. All students learned to examine the ultrasound videos in a computer-based learning environment where distinguishing two types of fetal movement patterns were taught: isolated movements and general movements, which are both complex movement patterns of several body parts. Results showed that on the total testing score, irrespective of the knowledge background, isolated movements were more difficult to determine than general ones. To understand this finding, analyses on subscales of test performance were calculated. Again, no main effect of knowledge background was found. A main effect of movement type revealed that detecting which body parts are involved in isolated movements is slightly easier than for general movements. Describing movement speed and amplitude, however, is more difficult for isolated movements than general movements. Moreover, an interaction effect showed that medical students can draw better conclusions on the (ab)normality of the movement for general movements than for isolated movements, while for the human-movement science students it is the reverse. These findings indicate that while biomedical knowledge enables students to learn to draw conclusions from complex movement patterns, knowledge of the biomechanics of human movement allows better judgement of simpler, isolated movements. Hence, it may be worth to consider both forms of knowledge in the medical curriculum.