Applying for a z visa am currently in China do I still need to do the medical check up in ghana?

Joe, I didn't get it. Do you hold another type in China right now? If so, do you plan to apply for a Z type without leaving? It depends on local entry and exit management bureau. If they require you to apply outside, then you need get back to your country to apply. In this way, you need to do the medical test two times. One is done for the application of Z type. The other is done for changing Z type into the resident permit when you arrive.

If you can apply in mainland, then you just need to do one medical examination. For your kids, I am afraid that you may not apply successfully in Ghana. I think you may contact the consular office for further consultation.
Tel: 030-2797437 (9:00-12:00 am, Tuesday & Thursday)