Design flow and selection of database for healthcare project

I have a requirement of assessing patients of their medical history and provide a vaccine from a internationally approved vaccine chart.

Flow/Design requirement:

1. I would be assessing medical records (form filled/prescription uploads) against the vaccine chart and if required the patient would have to undergo blood test/or any other medical test before getting vaccination.
2. Sometimes, they can be approved to get the vaccines straight away based on questionnaire they filled in (means they have no medical conditions)

For now, I am stuck at architecture design for first two pointers

I am using Riojs+nodejs(for API calls) and now I have decide on which DB I have to use? Mongo or Mysql ? or both together?

From some research, I see suggestions that User-centric data should be not be schemaless so that means that user profile such as username,password, user profile and medical history should be in RDBMS?

Also, there will be online payment done through third party payment provider and I need to capture success response.

My plan is to use it this way:

• Mongo db - store the vaccine chart and other information.
• Mysql - user-centric data.

Every time user signs-up/login, the info is pulled from mySql. For each assessment, Vaccine assessment is done against chart stored in mongo.

What are your suggestions?

I know this is a design question but I couldn't find a appropriate site to post this. Already tried http://ift.tt/2qW8IEQ but unable to add tags to question.