What do some of these abbreviations and numbers mean?

[John Salerno]

Can someone explain to me (in layman terms, mostly) what "b", "p", and "beta" stand for in Table 2 in this article:

 

http://www.plosone.o...al.pone.0017006

 

Also, I have trouble reading parts of the Tables (especially Table 2) because I don't have any sense of what "units" are being used for these values. In Table 1, mL is specified in one case, so that makes sense. In other sections it's simply the number of people in the study, but how do you read the numbers that don't have units, like the "Stress" or "Social support" values, or anything in Table 2?

 

Thanks.

Edited June 6, 2011 by John Salerno