How to setup replication conditions

How do I make a variable replicated based on certain conditions? I was reading documentation and they say…

"The replication definition specifies replication conditions, which describe when and if to replicate a given property to the client currently being considered."

They then gave some flags as examples for use in your conditionals for replicating the variable like bNetDirty, bNetInitial, and bNetOwner .
So my question is how do i make a variable only replicate under certain conditions like these?

I was always taught to declare replicated variables like this…
UPROPERTY(Replicated)
foat health;

So them saying that I can have it replicate under certain conditions confuses me. Would I for example then instead write it this way then?
UPROPERTY(Replicated, bNetDirty)
foat health;