This article explores a great idea, which is consistent with a lot of the things we already know about the immune system, including the fact that mood, among many other things, can affect it. However, Vedhara does not help her case when she says things like, “While not statistically significant, we found evidence that antibody levels in people who received our intervention appeared to be enhanced.”

Serum antibody levels jump all over the place, they go up, they go down, like a lot of things we measure in blood tests, for reasons known and unknown. What she is aiming to do here is to find out whether there is an effect on them because of mood. To do that, she has to get past the "noise" of fluctuations that occur from other causes. The way we do that is with statistics.

So if her data, when analyzed statistically, does not show the effect of mood on antibody levels, then, no, she does not have the evidence that she claims in this sentence. There was no evidence found in this study that mood affects anybody levels. Maybe mood effects anybody levels post vaccination, maybe it doesn't. This study is inconclusive.