The vampires that come from a world where they are 'alive' are much more complicated with almost countless differences and possibilities. This is because environment plays more of a role in determining how much risk they are. Which is why knowing as much about each world is important.
[Off the top of his head he gives a couple of examples to demonstrate this.]
Again, to start we have to begin with something physical--which is how vampires are made. Each world does things a little differently. In one world they might be born this way, passing on the gene from generation to generation-biologically being a vampire from the beginning. Other worlds may require the bite of a vampire in order to create new vampires--such as catching some sort of 'condition' that changes you from that moment on.
In most worlds I've found the latter to be the norm within worlds, but typically in worlds where there is a biological reproductive basis--both types do exist. So either vampires are able to reproduce and make more vampires--or they can't reproduce vampires at all. Only create them.
[He splits the alive section into 'Born' and 'Created'.]
And here is where the 'rules' of the world, culture, environment and personal experiences come into play. When I refer to 'rules' I'm referring to the physical impact just being a vampire requires each individual vampire to go through in that world.
In worlds where vampires can be born as well as created, there typically develops some sort of hierarchy among themselves depending on if they have the ability to cross-breed with humans or the formerly human vampires they have created. A class system is created naturally and how humanity is viewed by vampires is going to instantly create an impact on that class system.
Since humans are typically the prey of vampires it's likely going to leave them pretty low on that class system. This adds another issue to the vampires created in those worlds--as they used to be humans.
[Under 'Born' he writes the word 'hierarchy' and moves to the created side.]
So what we're left with are the created vampires, which we've touched on just a little already with the class system. Whatever physical and biological changes impact them because of this transformation: strength, changes to their brain chemistry, control over bloodlust, loss of soul-- these changes from world to world can make a huge impact on how dangerous they are. A vampire from a world where the transformation impacts their brain and moral compass is obviously going to hold more immediate danger than one from a world in which there is no impact to those areas.
[He puts the marker down after writing two question marks beneath 'Created']
But say you have two vampires from the same world--both turned around the same time from a world where vampires can only be created. Physically, the bloodlust is difficult for both of them and if they don't feed they slowly lose their mental capacity--leaving them at risk of attacking someone if they don't drink. The blood of humans is more desired and effective than the blood of vampires, but the consumption of vampire blood is possible and helps. Their world creates a 'sire' bond with the vampire who turned them and there is no way of breaking that--both of them were sired by the same vampire. Vampires are a secret in their world and their enemy is a small group of humans who have been personally impacted by their killing or transformation of a loved one. They have no real powers to fight vampires, just training and the desire for revenge.
So what is their risk? I do pretty much what you do, Dr. Reid--I profile them and assess it.