A meta-analysis on 463 papers from 2020
Question: How popular are the different imaging modalities?
Clinical and AI communities don’t value the modalities equally. Clinical publications are highly dominated by CT. AI papers mostly focus on X-Ray but underrate ultrasound.
Question: Where does the data come from?
Most data comes from China (48%), USA (12%) and Italy (11%).
Question: Where do they AI experts come from?
The AI experts mostly live in China (21%), USA (13%) and India (11%).
Question: Which other things did you find?
Well, most AI projects focus on COVID-19 detection/diagnosis although this is not the clinically most relevant tasks. Moreover, most projects are low-quality and prone to biases: Based on our systematic assessment of the maturity level of each publication only 12 publications (2.7%) were assigned a high maturity.
Question: But does the quality or the task not differ across modalities?
Yes, it does. Regarding modality, X-Ray projects have a significantly lower lower quality than CT papers (p < 1e-11). X-Ray papers also mostly focus on diagnostic tasks (87%) compared to CT (58%), partly due to the availability of public data. Also, the quality of diagnostic papers is significantly lower than for other tasks like disease prognosis or severity assessment.