The Cipriani study is a nice meta-analysis: "The random-effects summary SMD for all antidepressants was 0ยท30" This site explains SMD: http://handbook-5-1.cochrane.org/chapter_9/9_2_3_2_the_stand.... This site shows what 0.3 looks like (actually shows 0.2 and 0.5): http://rpsychologist.com/short-r-script-to-plot-effect-sizes.... Typically, when people are summarizing this line of research saying that there is no effect, they are talking about these kinds of effect sizes which look like they round to pretty much no effect. I think using SMD for reporting by itself is unfortunate: my understanding is that the drugs have large effects for a minority of patients -- rather than that they shift everyone's emotional experience over a little bit.
But note that there's no attempt to control for the (extremely strong) anti-histamine effects of these drugs (particularly elavil.) You need to test them against other anti-histamines which can also improve apparent health, a lot.