There is no main cagegory for non-graphical, non-educational medical software. Suggest main category "Medical". Note: According to the specification "additional categories" can only be used with a Main classification. What if no main classification applies?
Nowadays, you don't necessarily need a main category. But if you want to use one, you can use Science, which got promoted to main recently. I think that it covers your needs, so closing the bug.
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