1 fact table vs 3 fact tables

Hi,

I have question about fact table. Currently, we have one fact table which contains data from Lab, Medicine and Surgery. Our fact table currently have about 30 measure attributes (we combined all required attributes and flatten the table). Since three source do not have any common attribute, in our fact table, we have lot of 'n/a' attribute values.

If sources do not have any common attributes, would it be better to create 3 fact table using conformed dimension?

I was trying to build cube with SSAS, and seems like I can build single cube with multiple fact table, and I am not sure what would be trade offs for breaking our fact table to three vs current design.

Thank you.

It would be customary to use 3 fact tables.