Social Science Statistics Blog

Given the political and financial importance (the military has a budget for mental health), this is quite a difference. One critical issue pointed out by the Science article is that the original study did not adequately control for veterans who had been diagnosed for mental health problems before being sent to combat. Just looking at the overall rates after combat is not a great study design. But this also makes me wonder about how the data was collected in the first place. Maybe the most disabled veterans didn’t reply to the survey, or were in such state of illness that they couldn’t (or had died of related illnesses). The NVVRS is supposedly representative but this would be an interesting point to examine.

This article also illustrates how important the data, measures and codings are in social science research these days. It seems that taking these issues more seriously should be part of the academic and policy process just like replication should be (see here and here for some discussion this issue). While study and sample design are under much scrutiny these days, there are still few discussions about the sensitivity to coding and data. Given the difference they can make, this should change.