On: Depression and suicide linked to air pollution in ...

[civilian]

A treatment being a placebo implies nothing about the effect size!

[JamesBarney → civilian]

Most placebo effects are modest and the ones that aren't are usually mixed in with regression to the mean effects(which are usually pretty modest). So OP is implying that if an effect is especially large it's less likely to be placebo.

[btmorex → JamesBarney]

Placebo effects on depression are enormous.