But what's the problem with that if the difference between placebo's and the drugs is only so small?
On the treatment side, the difference between placebos and SSRIs is small. But again, SSRIs are only a small part of "the drugs". They're what we try first because they require very little oversight by the doctor and they work often enough, whether by large placebo response or by smaller genuine effect. But if they don't, there are second and third and fourth and more things we can try, ending with electroconvulsive therapy that works really well but is super difficult/expensive to administer.
But the bigger difference isn't in the treatment, it is in the diagnosis. Today we distinguish between about a dozen different mood disorders with different treatment plans (although most of these plans do involve SSRIs at some point). And most of all, we've gotten a lot better (though still not perfect) at distinguishing what is pathological and what is, say, a normal reaction to bereavement or an adaptive response to an abusive partner.
Without this knowledge, depression would often go unnoticed or one form of it would be mistaken for another. You have depression caused by a testosterone deficiency? You seem to be troubled, go pray. You have depression caused by lead poisoning? You seem to be troubled, go pray. You're decompensating and probably going to have a psychotic break within the month? You seem to be troubled, go pray.
It's not even clear that praying to a god who supposedly loves you has no positive effects and is worse than the the drugs.
Oh, prayer does have some positive effects. We call it religious coping and there are studies that prove it can help with (for example) fear of death in end stage cancer patients. But you have to be fairly intensely religious to get a measurable benefit, and it doesn't help a lot.
There are a few studies showing religiosity to be weakly negatively correlated with depression (example), and a few others showing it to be weakly positively correlated (example). If prayer helped a lot with depression the evidence would be much more clear cut.
There are also a variety of traditional remedies that should at least have placebo effects.
Yes. And terrible side effects, too. St John's Wort and Kava are among the worst examples. Or, again, Opium.
And if you count religious practice as a remedy, you should count the time and sacrifice it requires, as well as the wrong beliefs it entails, as side effects as well.
If prayer helped a lot with depression the evidence would be much more clear cut.
It doesn't have to be "a lot" to be better than the 1.80 points for SSRI's.
You have depression caused by a testosterone deficiency?
Do you have an estimate for the detection rates? How many people who have depression due to testosterone deficiency do you think do get accurately identified by our system?
Let alone people who have depression due to lead poisoning. I would estimate most of those not being identified by our present system.
...And if you count religiou
It's great to make people more aware of bad mental habits and encourage better ones, as many people have done on LessWrong. The way we deal with weak thinking is, however, like how people dealt with depression before the development of effective anti-depressants:
The only "anti-stupidity drugs" we have are nootropics. But the nootropics we have weren't developed as nootropics. Piracetam was, I think, developed to treat seizures. L-DOPA was developed to treat Parkinson's. No one knows who started using ginkgo biloba or what they used it for; it was used to treat asthma 5000 years ago. Adderall derives from drugs used to keep soldiers awake in World War 2.
And none of them are very good against stupidity. AFAIK, to date, not one drug has been developed by understanding and targeting the causes of different types of stupidity. We have the tools to do this--we could, for instance, sequence a lot of peoples' DNA, give them all IQ tests, and do a genome-wide association study, as a start.
We don't research these things because society doesn't want to research them. People don't conceive of stupidity as a disease that can be cured. We need, somehow, to promote thinking of stupidity as a mental illness. As something drug companies could make billions of dollars off of.