Color matters: placebo colored pills work better than white pills.
Delivery mechanism matters: placebo injections work better than pills.
Idk about price, packaging, or flavor specifically. But delivery mechanism, color, number of pills, etc I remember from a study.
[0] https://en.wikipedia.org/wiki/List_of_Ig_Nobel_Prize_winners...
Color matters: placebo colored pills work better than white pills.
Delivery mechanism matters: placebo injections work better than pills.
Idk about price, packaging, or flavor specifically. But delivery mechanism, color, number of pills, etc I remember from a study.