Anatomical examinations have been designed to assess topographical and/or applied knowledge of anatomy with or without the inclusion of visual resources such as cadaveric specimens or images, radiological images, and/or clinical photographs. Multimedia learning theories have advanced the understanding of how words and images are processed during learning. However, the evidence of the impact of including anatomical and radiological images within written assessments is sparse. This study investigates the impact of including images within clinically oriented single-best-answer questions on students' scores in a tailored online tool. Second-year medical students (n = 174) from six schools in the United Kingdom participated voluntarily in the examination, and 55 students provided free-text comments which were thematically analyzed. All questions were categorized as to whether their stimulus format was purely textual or included an associated image. The type (anatomical and radiological image) and deep structure of images (question referring to a bone or soft tissue on the image) were taken into consideration. Students scored significantly better on questions with images compared to questions without images (P < 0.001), and on questions referring to bones than to soft tissue (P < 0.001), but no difference was found in their performance on anatomical and radiological image questions. The coding highlighted areas of "test applicability" and "challenges faced by the students." In conclusion, images are critical in medical practice for investigating a patient's anatomy, and this study sets out a way to understand the effects of images on students' performance and their views in commonly employed written assessments.