On 2014 Feb 05, Michael Kraus commented:

We read this paper in the journal club I sponsor at the University of Illinois (each week we read an interesting social psychology article!). In general I find this topic to be fascinating--that one's mindset could change physiology and behavior in ways that lead to real gains in health is pretty neat!

I do have a question about the mean differences observed in the analysis: The groups have a standard deviation in weight that is about 22lbs (both at time 1 and time 2), and yet the standard error of the means used for the analysis is less than 1 lb. The repeated measures analysis must have accounted for a sizable portion of variability in weight, but I'm estimating, given how standard errors are calculated, that it wouldn't reduce the standard errors this drastically. My question: were there any data transformations or statistical techniques used to analyze the data that are not currently reported in the paper?

On 2014 Feb 05, Michael Kraus commented:

We read this paper in the journal club I sponsor at the University of Illinois (each week we read an interesting social psychology article!). In general I find this topic to be fascinating--that one's mindset could change physiology and behavior in ways that lead to real gains in health is pretty neat!

I do have a question about the mean differences observed in the analysis: The groups have a standard deviation in weight that is about 22lbs (both at time 1 and time 2), and yet the standard error of the means used for the analysis is less than 1 lb. The repeated measures analysis must have accounted for a sizable portion of variability in weight, but I'm estimating, given how standard errors are calculated, that it wouldn't reduce the standard errors this drastically. My question: were there any data transformations or statistical techniques used to analyze the data that are not currently reported in the paper?