Statistics and I have a love/hate relationship. It was probably my least favorite course in college, but I have to grudgingly admit statistics can provide some helpful information. Statistics can be skewed, but if the methodology is sound, the results can teach you some important things.
The Barna Group is well known in religious circles for their research on Christian issues. They specialize in trying to analyze what makes a person live (or not live) a truly Christian lifestyle. Their books are often bestsellers, perhaps because they try to sort out the difference between Christians “in name only” and those who are really close to “practicing what they preach”.