[emhs]

Well, one could call "Christianity" a superset of individual religions that fit within a certain range, and do the comparison off of individual denominations. That has the further advantage of demonstrating how individual denominations within Christianity often themselves have incompatible beliefs.

[jamesgeck0]

One would also need to weight the beliefs. Various denominations disagree about topics like predestination, but don't ultimately place a lot of value on those topics. There are often many people in the same denomination who don't necessarily agree with every official bit of low weighted doctrine.

Theology about the nature of Christ has significantly higher weight. Heresy, etc. This is where you see little diversion between denominations and more diversion between, say, Protestants and the LDS Church.