I want to know the required material needed for applying visa as medical tourist

I want to visit beijing with my parents for my medical treatment. My I please know what documents i need if i want to apply for visa for 30 days?
During my visit i will go to 3 hospitals in Beijing
1- Puhua international Hospital
2- Chinese military hospital
3- Re-life international medical centre
May i please also know that how many days will be needed for visa approval.