It's hard to control for all the variables in any study, though. Arguing about correlation versus causation is actually a fairly good way to destroy most any study.
"But it's hard" is not the greatest defense for not doing proper controls. Any researcher who can't control their variables shouldn't be researching (and by extension any field
of scientific research that can't, isn't worthy of the name).
Okay, a cursory reading shows us the top five reasons why this article is not worth the paper it was printed on:1) sample size of under 300, all college undergraduates
Clearly not the best sample for saying assaying normal reactions, especially not on a test dealing with depression and sexuality. I remember being an undergrad. Being depressed and having sex were practically pastimes at my alma mater. We could have formed a league <_<2) fundamentally fails by providing no causative mechanism
The closest it comes is: huh, females are often depressed about reproductive issues "such as death of a child, miscarriage, and menopause" let's hypothesize that a load of hormones randomly absorbed through the vaginal wall (and while we are at it we are hypothesizing that is possible in biologically significant doses) will make them happy.3) females who used condoms had less sex in general, by as much as 100 instances of intercourse a year, one of the questions used to assay depression is how interested you are in sex
Clearly skewing themselves here. 4) relatively large deviations on the depression test (in one group a mean of 15 with a SD of 11), also only one group had a mean score above "minimal depression"
And that one group was "usually". The mean of "always" using a condom was in minimal depression, the same category as "never".
Which leads us to our last and perhaps, most damning of all:5) those who used condoms "usually" were the most depressed group; significantly more depressed according to the test than the "always" group and had a significantly higher rate of suicide attempt than those who used condoms "always" (29% vs 13%, more than double)
Which is, obviously, counter their hypothesis.
And as a bonus they openly admit that they didn't control for oral contraception (which they also admit that a "substantial number" of females in all categories except "abstinent" were using) use and its effects on mood.
I have no clue how something like this was even published. The only thing we have learned about here is the high rate of unprotected sex on college campuses. Something I think most of us were aware of.